Smart Radiation Therapy Biomaterials.

PubMed

Ngwa, Wilfred; Boateng, Francis; Kumar, Rajiv; Irvine, Darrell J; Formenti, Silvia; Ngoma, Twalib; Herskind, Carsten; Veldwijk, Marlon R; Hildenbrand, Georg Lars; Hausmann, Michael; Wenz, Frederik; Hesser, Juergen

2017-03-01

Radiation therapy (RT) is a crucial component of cancer care, used in the treatment of over 50% of cancer patients. Patients undergoing image guided RT or brachytherapy routinely have inert RT biomaterials implanted into their tumors. The single function of these RT biomaterials is to ensure geometric accuracy during treatment. Recent studies have proposed that the inert biomaterials could be upgraded to "smart" RT biomaterials, designed to do more than 1 function. Such smart biomaterials include next-generation fiducial markers, brachytherapy spacers, and balloon applicators, designed to respond to stimuli and perform additional desirable functions like controlled delivery of therapy-enhancing payloads directly into the tumor subvolume while minimizing normal tissue toxicities. More broadly, smart RT biomaterials may include functionalized nanoparticles that can be activated to boost RT efficacy. This work reviews the rationale for smart RT biomaterials, the state of the art in this emerging cross-disciplinary research area, challenges and opportunities for further research and development, and a purview of potential clinical applications. Applications covered include using smart RT biomaterials for boosting cancer therapy with minimal side effects, combining RT with immunotherapy or chemotherapy, reducing treatment time or health care costs, and other incipient applications. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of diagnostic performance between single- and multiphasic contrast-enhanced abdominopelvic computed tomography in patients admitted to the emergency department with abdominal pain: potential radiation dose reduction.

PubMed

Hwang, Shin Hye; You, Je Sung; Song, Mi Kyong; Choi, Jin-Young; Kim, Myeong-Jin; Chung, Yong Eun

2015-04-01

To evaluate feasibility of radiation dose reduction by optimal phase selection of computed tomography (CT) in patients who visited the emergency department (ED) for abdominal pain. We included 253 patients who visited the ED for abdominal pain. They underwent multiphasic CT including precontrast, late arterial phase (LAP), and hepatic venous phase (HVP). Three image sets (HVP, precontrast + HVP, and precontrast + LAP + HVP) were reviewed. Two reviewers determined the most appropriate diagnosis with five-point confidence scale. Diagnostic performances were compared among image sets by weighted-least-squares method or DeLong's method. Linear mixed model was used to assess changes of diagnostic confidence and radiation dose. There was no difference in diagnostic performance among three image sets, although diagnostic confidence level was significantly improved after review of triphasic images compared with both HVP images only or HVP with precontrast images (confidence scale, 4.64 ± 0.05, 4.66 ± 0.05, and 4.76 ± 0.04 in the order of the sets; overall P = 0.0008). Similar trends were observed in the subgroup analysis for diagnosis of pelvic inflammatory disease and cholecystitis. There is no difference between HVP-CT alone and multiphasic CT for the diagnosis of causes of abdominal pain in patients admitted to the ED without prior chronic disease or neoplasia. • There was no difference in diagnostic performance of HVP CT and multiphasic CT. • The diagnostic confidence level was improved after review of the LAP images. • HVP CT can achieve diagnostic performance similar to that of multiphasic CT, while minimizing radiation.

Radiation therapy in the neonate

SciTech Connect

Littman, P.; D'Angio, G.J.

Radiation therapy (RT) is frequently used in the management of children with cancer, but neonatal neoplasms are rare. Newborns represent 1.5% of the children with malignant diseases in the Tumor Registry at the Children's Hospital of Philadelphia over the last 30 years. Thus, occasionally the pediatrics radiation therapist must consider treating the very young infant. The specific radiation effects on growth and development must be weighed in reaching a therapeutic decision. All children are vulnerable to the late effects of radiation therapy, but the neonates may be more susceptible because of the immaturity of important organs such as the brain,more » lung, liver, kidney, and bone. In general, radiation therapy, should be avoided during the first several weeks of life because of the potential increased sensitivity of the liver and kidneys during that period. If radiation therapy is used at all during infancy, the benefits must be weighed against the possibility of significant late effects. Increasing knowledge of pediatric neoplasms has shown that some tumors (such as mesoblastic nephroma) require no treatment except for surgical excision; and other tumors, such as Stage IV-S neuroblastoma, may require very little treatment. In those tumors that require radiation therapy, the use of chemotherapy may allow reduction of the radiation dose. Furthermore, alterations of time-dose-fractionation schemes and careful attention to tumor volume with the use of special techniques, such as ''shrinking fields,'' may decrease the late adverse effects of treatment.« less

[Radiation therapy and redox imaging].

PubMed

Matsumoto, Ken-ichiro

2015-01-01

Radiation therapy kills cancer cells in part by flood of free radicals. Radiation ionizes and/or excites water molecules to create highly reactive species, i.e. free radicals and/or reactive oxygen species. Free radical chain reactions oxidize biologically important molecules and thereby disrupt their function. Tissue oxygen and/or redox status, which can influence the course of the free radical chain reaction, can affect the efficacy of radiation therapy. Prior observation of tissue oxygen and/or redox status is helpful for planning a safe and efficient course of radiation therapy. Magnetic resonance-based redox imaging techniques, which can estimate tissue redox status non-invasively, have been developed not only for diagnostic information but also for estimating the efficacy of treatment. Redox imaging is now spotlighted to achieve radiation theranostics.

Method for microbeam radiation therapy

DOEpatents

Slatkin, Daniel N.; Dilmanian, F. Avraham; Spanne, Per O.

1994-01-01

A method of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation, in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue.

Method for microbeam radiation therapy

DOEpatents

Slatkin, D.N.; Dilmanian, F.A.; Spanne, P.O.

1994-08-16

A method is disclosed of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation. The dose is in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue. No Drawings

Radiation therapy and esophageal cancer.

PubMed

Shridhar, Ravi; Almhanna, Khaldoun; Meredith, Kenneth L; Biagioli, Matthew C; Chuong, Michael D; Cruz, Alex; Hoffe, Sarah E

2013-04-01

Squamous cell carcinoma and adenocarcinoma account for more than 90% of all esophageal cancer cases. Although the incidence of squamous cell carcinoma has declined, the incidence of adenocarcinoma has risen due to increases in obesity and gastroesophageal reflux disease. The authors examine the role of radiation therapy alone (external beam and brachytherapy) for the management of esophageal cancer or combined with other modalities. The impact on staging and appropriate stratification of patients referred for curative vs palliative intent with modalities is reviewed. The authors also explore the role of emerging radiation technologies. Current data show that neoadjuvant chemoradiotherapy followed by surgical resection is the accepted standard of care, with 3-year overall survival rates ranging from 30% to 60%. The benefit of adjuvant radiation therapy is limited to patients with node-positive cancer. The survival benefit of surgical resection after chemoradiotherapy remains controversial. External beam radiation therapy alone results in few long-term survivors and is considered palliative at best. Radiation dose-escalation has failed to improve local control or survival. Brachytherapy can provide better long-term palliation of dysphagia than metal stent placement. Although three-dimensional conformal treatment planning is the accepted standard, the roles of IMRT and proton therapy are evolving and potentially reduce adverse events due to better sparing of normal tissue. Future directions will evaluate the benefit of induction chemotherapy followed by chemoradiotherapy, the role of surgery in locally advanced disease, and the identification of responders prior to treatment based on microarray analysis.

Intra-operative electron beam radiotherapy and abdomino-pelvic surgery for cancer: influence on immunological parameters.

PubMed

Bussières, E; Richaud, P; Gualde, N

1992-10-01

Evolution of some immunological parameters was observed during the first month in 20 patients with different abdomino-pelvic cancers who underwent surgery with intra-operative radiation therapy (IORT) (mean dose of 19.44 Gy, range 15, 25). Observed parameters before (DO-) and after procedure (DO+), on seventh (D7) and fourteenth (D14) days and fifth week (D30) were: lymphocyte count, lymphocyte subsets (CD19, CD3, CD4, CD8, CD56), natural killer (NK) activity, immunoglobulins, C3 and C4b fractions of complement, soluble receptor for interleukin 2 (sIL2-R). Results showed a decrease of circulating lymphocytes (DO-: 1189 +/- 168 cells/mm3; D7: 889 +/- 91; P = 0.011), of absolute number of CD3 lymphocytes (DO-: 785 +/- 114 cells/mm3; D7: 563 +/- 86; P = 0.025), of CD4 lymphocytes (DO-: 441 +/- 70 cells/mm3; DO+: 299 +/- 43; P = 0.013) and of CD8 lymphocytes (DO-:361 +/- 50 cells/mm3, D7:250 +/- 44; P = 0.006). All values returned towards preoperative levels by D30. Absolute number of NK cells was unchanged but NK activity was significantly diminished (effector target ratio 5:1 DO-:33 +/- 5%; DO+:44 +/- 7%; D7:18 +/- 3%; D14:21 +/- 4%; D30:25 +/- 4%). sIL2-R was significantly enhanced from D7 to D30. All these impairments are moderate and these observations provide some evidence of satisfactory tolerance to IORT for abdomino-pelvic cancers during the immediate postoperative period.

Radiation therapy for prostate cancer.

PubMed

Koontz, Bridget F; Lee, W Robert

2013-07-01

Radiation therapy is an effective treatment for newly diagnosed prostate cancer, salvage treatment, or for palliation of advanced disease. Herein we briefly discuss the indications, results, and complications associated with brachytherapy and external beam radiotherapy, when used as monotherapy and in combination with each other or androgen deprivation. Copyright © 2013 Elsevier Inc. All rights reserved.

[Interventional radiology and radiation therapy].

PubMed

Hadjiev, Janaki

2015-04-26

The revolutionary role of modern cross-sectional imaging, the improved target definition in CT/MRI image guided brachytherapy, the precise topography for applicator and anatomy contribute to a better knowledge and management of tumors and critical organs. Further developments and functional imaging is expected to lead to a broad use of patient tailored therapy in the field of interventional radiation oncology.

Radiation Therapy and Hearing Loss

SciTech Connect

Bhandare, Niranjan; Jackson, Andrew; Eisbruch, Avraham

2010-03-01

A review of literature on the development of sensorineural hearing loss after high-dose radiation therapy for head-and-neck tumors and stereotactic radiosurgery or fractionated stereotactic radiotherapy for the treatment of vestibular schwannoma is presented. Because of the small volume of the cochlea a dose-volume analysis is not feasible. Instead, the current literature on the effect of the mean dose received by the cochlea and other treatment- and patient-related factors on outcome are evaluated. Based on the data, a specific threshold dose to cochlea for sensorineural hearing loss cannot be determined; therefore, dose-prescription limits are suggested. A standard for evaluating radiation therapy-associatedmore » ototoxicity as well as a detailed approach for scoring toxicity is presented.« less

Applications of Machine Learning for Radiation Therapy.

PubMed

Arimura, Hidetaka; Nakamoto, Takahiro

2016-01-01

Radiation therapy has been highly advanced as image guided radiation therapy (IGRT) by making advantage of image engineering technologies. Recently, novel frameworks based on image engineering technologies as well as machine learning technologies have been studied for sophisticating the radiation therapy. In this review paper, the author introduces several researches of applications of machine learning for radiation therapy. For examples, a method to determine the threshold values for standardized uptake value (SUV) for estimation of gross tumor volume (GTV) in positron emission tomography (PET) images, an approach to estimate the multileaf collimator (MLC) position errors between treatment plans and radiation delivery time, and prediction frameworks for esophageal stenosis and radiation pneumonitis risk after radiation therapy are described. Finally, the author introduces seven issues that one should consider when applying machine learning models to radiation therapy.

[Highly quality-controlled radiation therapy].

PubMed

Shirato, Hiroki

2005-04-01

Advanced radiation therapy for intracranial disease has focused on set-up accuracy for the past 15 years. However, quality control in the prescribed dose is actually as important as the tumor set-up in radiation therapy. Because of the complexity of the three-dimensional radiation treatment planning system in recent years, the highly quality-controlled prescription of the dose has now been reappraised as the mainstream to improve the treatment outcome of radiation therapy for intracranial disease. The Japanese Committee for Quality Control of Radiation Therapy has developed fundamental requirements such as a QC committee in each hospital, a medical physicist, dosimetrists (QC members), and an external audit.

External Beam Radiation Therapy for Cancer

Cancer.gov

External beam radiation therapy is used to treat many types of cancer. it is a local treatment, where a machine aims radiation at your cancer. Learn more about different types of external beam radiation therapy, and what to expect if you're receiving treatment.

Missed Radiation Therapy and Cancer Recurrence

Cancer.gov

Patients who miss radiation therapy sessions during cancer treatment have an increased risk of their disease returning, even if they eventually complete their course of radiation treatment, according to a new study.

Partial breast radiation therapy - external beam

MedlinePlus

APBI is used to prevent breast cancer from coming back. When radiation therapy is given after breast- ... breast conservation therapy reduces the risk of cancer coming back, and possibly even death from breast cancer.

Radiobiology of systemic radiation therapy.

PubMed

Murray, David; McEwan, Alexander J

2007-02-01

Although systemic radionuclide therapy (SRT) is effective as a palliative therapy in patients with metastatic cancer, there has been limited success in expanding patterns of utilization and in bringing novel systemic radiotherapeutic agents to routine clinical use. Although there are many factors that contribute to this situation, we hypothesize that a better understanding of the radiobiology and mechanism of action of SRT will facilitate the development of future compounds and the future designs of prospective clinical trials. If these trials can be rationalized to the biological basis of the therapy, it is likely that the long-term outcome would be enhanced therapeutic efficacy. In this review, we provide perspectives of the current state of low-dose-rate (LDR) radiation research and offer linkages where appropriate with current clinical knowledge. These include the recently described phenomena of low-dose hyper-radiosensitivity-increased radioresistance (LDH-IRR), adaptive responses, and biological bystander effects. Each of these areas require a major reconsideration of existing models for radiation action and an understanding of how this knowledge will integrate into the evolution of clinical SRT practice. Validation of a role in vivo for both LDH-IRR and biological bystander effects in SRT would greatly impact the way we would assess therapeutic response to SRT, the design of clinical trials of novel SRT radiopharmaceuticals, and risk estimates for both therapeutic and diagnostic radiopharmaceuticals. We believe that the current state of research in LDR effects offers a major opportunity to the nuclear medicine community to address the basic science of clinical SRT practice, to use this new knowledge to expand the use and roles of SRT, and to facilitate the introduction of new therapeutic radiopharmaceuticals.

Melioidosis: reactivation during radiation therapy

SciTech Connect

Jegasothy, B.V.; Goslen, J.B.; Salvatore, M.A.

1980-05-01

Melioidosis is caused by Pseudomonas pseudomallei, a gram-negative, motile bacillus which is a naturally occurring soil saprophyte. The organism is endemic in Southeast Asia, the Philippines, Australia, and parts of Central and South America. Most human disease occurs from infection acquired in these countries. Infection with P pseudomallei may produce no apparent clinical disease. Acute pneumonitis or septicemia may result from inhalation of the organism, and inoculation into sites of trauma may cause localized skin abscesses, or the disease may remain latent and be reactivated months or years later by trauma, burns, or pneumococcal pneumonia, diabetic ketoacidosis, influenza, or bronchogenicmore » carcinoma. The last is probably the commonest form of melioidosis seen in the United States. We present the first case of reactivation of melioidosis after radiation therapy for carcinoma of the lung, again emphasizing the need to consider melioidosis in a septic patient with a history of travel, especially to Southeast Asia.« less

Job satisfaction among radiation therapy educators.

PubMed

Swafford, Larry G; Legg, Jeffrey S

2007-01-01

Job satisfaction is one of the most consistent variables related to employee retention and is especially relevant considering the shortage of radiation therapists and radiation therapy educators in the United States. To investigate job satisfaction levels among radiation therapy educators certified by the American Registry of Radiologic Technologists and employed in programs accredited by the Joint Review Committee on Education in Radiologic Technology. The long form of the Minnesota Satisfaction Questionnaire (MSQ) was mailed to 158 radiation therapy educators to measure job satisfaction. Overall job satisfaction and subscales were calculated based on MSQ methodology. A total of 90 usable surveys were returned for a 56.9% response rate. With a "general satisfaction" score of 69.64, radiation therapy educators ranked in the lowest 25th percentile of the nondisabled norm scale for job satisfaction. Respondents reported higher degrees of job satisfaction on the moral values, social service and achievement subscales. Lower job satisfaction levels were associated with the company policies and practices, advancement and compensation subscales. Radiation therapy educators report low job satisfaction. Educational institutions must tailor recruitment and retention efforts to better reflect the positive aspects of being a radiation therapy educator. Furthermore, improving retention and recruitment efforts might help offset the current shortages of radiation therapy educators and, ultimately, clinical radiation therapists.

Selection of symptomatic patients with Crohn's disease for abdominopelvic computed tomography: role of serum C-reactive protein.

PubMed

Desmond, Alan N; O'Regan, Kevin; Malik, Neera; McWilliams, Sebastian; O'Neill, Siobhan; Quigley, Eamonn M; Shanahan, Fergus; Maher, Michael M

2012-11-01

Results of previous studies have shown that repeated abdominopelvic computed tomography (CT) examinations can lead to substantial cumulative diagnostic radiation exposure in patients with Crohn's disease (CD). Improved selection of patients referred for CT will reduce unnecessary radiation exposure. This study examines if serum C-reactive protein (CRP) concentration predicts which symptomatic patients with CD are likely to have significant disease activity or disease complications (such as abscess) detected on abdominopelvic CT. All abdominopelvic CTs performed on patients with CD at a tertiary referral centre during the period June 2003 to June 2008 were identified. CT findings were coded by a pair of independent blinded senior radiologists for (i) small bowel luminal disease, (ii) large bowel luminal disease, (iii) mesenteric inflammatory changes, (iv) penetrating disease (fistulas, abscess, or phlegmon), (v) acute disease complications (obstruction or perforation), and (vi) acute non-CD findings. Imaging findings were correlated with serum CRP checked within 14 days before imaging. The reference range for CRP was defined as 0-5 mg/L. A total of 147 patients with symptomatic CD had a CRP assay performed within 14 days before undergoing abdominopelvic CT. The median time from CRP assay to imaging was 2 days (interquartile range, 0-6 days). Median CRP before imaging was 24 mg/L (interquartile range, 6-88 mg/L). CT was normal in 34 of 147 case (23.1%). Patients with normal CRP (n = 36) were significantly less likely to have penetrating disease (odds ratio [OR], 0.04 [95% confidence interval {CI}, 0.01-0.7]; P < .001) or large bowel luminal disease (OR, 0.3 [95% CI, 0.1-0.8]; P < .05). Normal CRP excluded penetrating disease with a sensitivity of 1.0 (95% CI, 0.87-1.0). CRP levels did not correlate with the presence of small bowel luminal disease (n = 82), mesenteric inflammatory changes (n = 68), or acute disease complications (n = 10). Symptomatic patients with CD

Recent advances in radiation cancer therapy

NASA Astrophysics Data System (ADS)

Ma, C.-M. Charlie

2007-03-01

This paper presents the recent advances in radiation therapy techniques for the treatment of cancer. Significant improvement has been made in imaging techniques such as CT, MRI, MRS, PET, ultrasound, etc. that have brought marked advances in tumor target and critical structure delineation for treatment planning and patient setup and target localization for accurate dose delivery in radiation therapy of cancer. Recent developments of novel treatment modalities including intensity-modulated x-ray therapy (IMXT), energy- and intensity modulated electron therapy (MERT) and intensity modulated proton therapy (IMPT) together with the use of advanced image guidance have enabled precise dose delivery for dose escalation and hypofractionation studies that may result in better local control and quality of life. Particle acceleration using laser-induced plasmas has great potential for new cost-effective radiation sources that may have a great impact on the management of cancer using radiation therapy.

Radiation therapy facilities in the United States

SciTech Connect

Ballas, Leslie K.; Elkin, Elena B.; Schrag, Deborah

2006-11-15

Purpose: About half of all cancer patients in the United States receive radiation therapy as a part of their cancer treatment. Little is known, however, about the facilities that currently deliver external beam radiation. Our goal was to construct a comprehensive database of all radiation therapy facilities in the United States that can be used for future health services research in radiation oncology. Methods and Materials: From each state's health department we obtained a list of all facilities that have a linear accelerator or provide radiation therapy. We merged these state lists with information from the American Hospital Association (AHA),more » as well as 2 organizations that audit the accuracy of radiation machines: the Radiologic Physics Center (RPC) and Radiation Dosimetry Services (RDS). The comprehensive database included all unique facilities listed in 1 or more of the 4 sources. Results: We identified 2,246 radiation therapy facilities operating in the United States as of 2004-2005. Of these, 448 (20%) facilities were identified through state health department records alone and were not listed in any other data source. Conclusions: Determining the location of the 2,246 radiation facilities in the United States is a first step in providing important information to radiation oncologists and policymakers concerned with access to radiation therapy services, the distribution of health care resources, and the quality of cancer care.« less

Scrub typhus: radiological and clinical findings in abdominopelvic involvement.

PubMed

Kim, Kun Yung; Song, Ji Soo; Park, Eun Hae; Jin, Gong Yong

2017-03-01

To describe the clinical and radiological findings of abdominopelvic involvement in scrub typhus. Abdominopelvic computed tomography (CT) of 78 patients with scrub typhus were evaluated by two readers. The presence of gallbladder wall thickening, arterial inhomogeneous enhancement of the liver, periportal edema, splenic infarction, hepatomegaly, splenomegaly, ascites, pleural effusion, and sites of lymphadenopathy were evaluated. Patients were divided into four clinical subgroups according to laboratory findings. Association between imaging findings and subgroups was analyzed by Chi squared test or Fisher's exact test. The most common CT finding was hepatomegaly (74.4%), followed by splenomegaly (66.7%). The majority of patients had at least three areas of abdominopelvic lymphadenopathy (71.8%). Pelvic lymphadenopathy was most commonly seen when eschar was found in the ipsilateral lower extremity (left, n = 5/7; right, n = 8/13). Significant association between hepatic dysfunction and perigastric lymphadenopathy was documented (p = 0.03). Scrub typhus has a spectrum of variable clinical and radiological findings mimicking those of acute hepatitis. Diffuse abdominopelvic lymphadenopathy involving the retroperitoneum and pelvic area may aid in early diagnosis of scrub typhus. Perigastric lymphadenopathy could be a sign of severe scrub typhus combined with hepatic dysfunction.

Radiation Sensitization in Cancer Therapy.

ERIC Educational Resources Information Center

Greenstock, Clive L.

1981-01-01

Discusses various aspects of radiation damage to biological material, including free radical mechanisms, radiation sensitization and protection, tumor hypoxia, mechanism of hypoxic cell radiosensitization, redox model for radiation modification, sensitizer probes of cellular radiation targets, pulse radiolysis studies of free radical kinetics,…

Radiation Therapy for Skin Cancer

MedlinePlus

... ask friends, family, support groups and your radiation oncology treatment team for help. Visit www.rtanswers.org ... rtanswers.org LEARNING ABOUT CLINICAL TRIALS The radiation oncology treatment team is constantly exploring new ways to ...

Radiation Therapy for Gynecologic Cancers

MedlinePlus

... A RE LEARNING ABOUT CLINICAL TRIALS The radiation oncology team is constantly exploring new ways to treat ... Cl inical Trials. gov www.clinicaltrials.gov NRG Oncology (Clinical Trials Using Radiation) www.nrgoncology.org Gynecologic ...

Nursing care update: Internal radiation therapy

SciTech Connect

Lowdermilk, D.L.

Internal radiation therapy has been used in treating gynecological cancers for over 100 years. A variety of radioactive sources are currently used alone and in combination with other cancer treatments. Nurses need to be able to provide safe, comprehensive care to patients receiving internal radiation therapy while using precautions to keep the risks of exposure to a minimum. This article discusses current trends and issues related to such treatment for gynecological cancers.20 references.

42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 2 2012-10-01 2012-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy and...

42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 2 2011-10-01 2011-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy and...

42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 2 2013-10-01 2013-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy and...

42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 2 2014-10-01 2014-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy and...

42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 2 2010-10-01 2010-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy and...

How Does Proton Radiation Therapy Work?

SciTech Connect

Lincoln, Don

A cancer diagnosis can be a devastating thing to hear, but new treatments are greatly improving a person’s chance of being cured. In this video, Fermilab’s Dr. Don Lincoln explains the physics of an exciting treatment option, called proton radiation therapy, which is far superior to traditional therapy, at least in some cases.

The role of interventional radiology in abdominopelvic trauma

PubMed Central

Ierardi, Anna Maria; Duka, Ejona; Lucchina, Natalie; Floridi, Chiara; De Martino, Alessandro; Donat, Daniela; Fontana, Federico

2016-01-01

The management of trauma patients has evolved in recent decades owing to increasing availability of advanced imaging modalities such as CT. Nowadays, CT has replaced the diagnostic function of angiography. The latter is considered when a therapeutic option is hypothesized. Arterial embolization is a life-saving procedure in abdominopelvic haemorrhagic patients, reducing relevant mortality rates and ensuring haemodynamic stabilization of the patient. Percutaneous transarterial embolization has been shown to be effective for controlling ongoing bleeding for patients with high-grade abdominopelvic injuries, thereby reducing the failure rate of non-operative management, preserving maximal organ function. Surgery is not always the optimal solution for stabilization of a patient with polytrauma. Mini-invasivity and repeatability may be considered as relevant advantages. We review technical considerations, efficacy and complication rates of hepatic, splenic, renal and pelvic embolization to extrapolate current evidence about transarterial embolization in traumatic patients. PMID:26642310

Stereotactic body radiation therapy for oligometastases.

PubMed

Lo, Simon S; Fakiris, Achilles J; Teh, Bin S; Cardenes, Higinia R; Henderson, Mark A; Forquer, Jeffrey A; Papiez, Lech; McGarry, Ronald C; Wang, Jian Z; Li, Kaile; Mayr, Nina A; Timmerman, Robert D

2009-05-01

The standard treatment for metastatic cancer is systemic therapy. However, in a subset of patients with limited extracranial metastases or oligometastases, local ablative therapy in combination with systemic therapy may improve treatment outcomes. Stereotactic body radiation therapy (SBRT) has emerged as a novel approach for local ablation of extracranial oligometastases. There is a good body of experience in the use of SBRT for the treatment of oligometastases in various sites including the lung, the liver and the spine with promising results. This article provides an overview of the use of SBRT in the management of extracranial oligometastases.

Radiation Therapy for Locally Advanced Esophageal Cancer.

PubMed

Chun, Stephen G; Skinner, Heath D; Minsky, Bruce D

2017-04-01

The treatment of locally advanced esophageal cancer is controversial. For patients who are candidates for surgical resection, multiple prospective clinical trials have demonstrated the advantages of neoadjuvant chemoradiation. For patients who are medically inoperable, definitive chemoradiation is an alternative approach with survival rates comparable to trimodality therapy. Although trials of dose escalation are ongoing, the standard radiation dose remains 50.4 Gy. Modern radiotherapy techniques such as image-guided radiation therapy with motion management and intensity-modulated radiation therapy are strongly encouraged with a planning objective to maximize conformity to the intended target volume while reducing dose delivered to uninvolved normal tissues. Copyright © 2016 Elsevier Inc. All rights reserved.

Urethroplasty After Radiation Therapy for Prostate Cancer

PubMed Central

Glass, Allison S.; McAninch, Jack W.; Zaid, Uwais B.; Cinman, Nadya M.; Breyer, Benjamin N.

2013-01-01

OBJECTIVE To report urethroplasty outcomes in men who developed urethral stricture after undergoing radiation therapy for prostate cancer. METHODS Our urethroplasty database was reviewed for cases of urethral stricture after radiation therapy for prostate cancer between June 2004 and May 2010. Patient demographics, prostate cancer therapy type, stricture length and location, and type of urethroplasty were obtained. All patients received clinical evaluation, including imaging studies post procedure. Treatment success was defined as no need for repeat surgical intervention. RESULTS Twenty-nine patients underwent urethroplasty for radiation-induced stricture. Previous radiation therapy included external beam radiotherapy (EBRT), radical prostatectomy (RP)/EBRT, EBRT/brachytherapy (BT) and BT alone in 11 (38%), 7 (24%), 7 (24%), and 4 (14%) patients, respectively. Mean age was 69 (±6.9) years. Mean stricture length was 2.6 (±1.6) cm. Anastomotic urethroplasty was performed in 76% patients, buccal mucosal graft in 17%, and perineal flap repair in 7%. Stricture was localized to bulbar urethra in 12 (41%), membranous in 12 (41%), vesicourethra in 3 (10%), and pan-urethral in 2 (7%) patients. Overall success rate was 90%. Median follow-up was 40 months (range 12-83). Time to recurrence ranged from 6-16 months. CONCLUSION Multiple forms of urethroplasty appear to be viable options in treating radiation-induced urethral stricture. Future studies are needed to examine the durability of repairs. PMID:22521189

Radiation Therapy for Pilocytic Astrocytomas of Childhood

SciTech Connect

Mansur, David B., E-mail: mansur@radonc.wustl.ed; Rubin, Joshua B.; Kidd, Elizabeth A.

Purpose: Though radiation therapy is generally considered the most effective treatment for unresectable pilocytic astrocytomas in children, there are few data to support this claim. To examine the efficacy of radiation therapy for pediatric pilocytic astrocytomas, we retrospectively reviewed the experience at our institution. Methods and Materials: Thirty-five patients 18 years old or younger with unresectable tumors and without evidence of neurofibromatosis have been treated since 1982. Patients were treated with local radiation fields to a median dose of 54 Gy. Six patients were treated with radiosurgery to a median dose of 15.5 Gy. Five patients were treated with initialmore » chemotherapy and irradiated after progression. Results: All patients were alive after a median follow-up of 5.0 years. However, progression-free survival was 68.7%. None of 11 infratentorial tumors progressed compared with 6 of 20 supratentorial tumors. A trend toward improved progression-free survival was seen with radiosurgery (80%) compared with external beam alone (66%), but this difference did not reach statistical significance. Eight of the 9 patients progressing after therapy did so within the irradiated volume. Conclusions: Although the survival of these children is excellent, almost one third of patients have progressive disease after definitive radiotherapy. Improvements in tumor control are needed in this patient population, and the optimal therapy has not been fully defined. Prospective trials comparing initial chemotherapy to radiation therapy are warranted.« less

Targeted Radiation Therapy for Cancer Initiative

DTIC Science & Technology

2012-09-01

pelvic floor . Problem Areas: As previously reported, it was unanimously decided to discontinue efforts at VAPSHCS based on several factors...Calypso system, 3) whether Beacon® Transponder is of benefit in pelvic radiation therapy following prostatectomy, 4) whether hypofractionated treatment...Localization System occurred at MAMC. The radiation team continues to receive training and technical support of the system from Calypso as needed

Advanced Small Animal Conformal Radiation Therapy Device.

PubMed

Sharma, Sunil; Narayanasamy, Ganesh; Przybyla, Beata; Webber, Jessica; Boerma, Marjan; Clarkson, Richard; Moros, Eduardo G; Corry, Peter M; Griffin, Robert J

2017-02-01

We have developed a small animal conformal radiation therapy device that provides a degree of geometrical/anatomical targeting comparable to what is achievable in a commercial animal irradiator. small animal conformal radiation therapy device is capable of producing precise and accurate conformal delivery of radiation to target as well as for imaging small animals. The small animal conformal radiation therapy device uses an X-ray tube, a robotic animal position system, and a digital imager. The system is in a steel enclosure with adequate lead shielding following National Council on Radiation Protection and Measurements 49 guidelines and verified with Geiger-Mueller survey meter. The X-ray source is calibrated following AAPM TG-61 specifications and mounted at 101.6 cm from the floor, which is a primary barrier. The X-ray tube is mounted on a custom-made "gantry" and has a special collimating assembly system that allows field size between 0.5 mm and 20 cm at isocenter. Three-dimensional imaging can be performed to aid target localization using the same X-ray source at custom settings and an in-house reconstruction software. The small animal conformal radiation therapy device thus provides an excellent integrated system to promote translational research in radiation oncology in an academic laboratory. The purpose of this article is to review shielding and dosimetric measurement and highlight a few successful studies that have been performed to date with our system. In addition, an example of new data from an in vivo rat model of breast cancer is presented in which spatially fractionated radiation alone and in combination with thermal ablation was applied and the therapeutic benefit examined.

Process of Coping with Radiation Therapy.

ERIC Educational Resources Information Center

Johnson, Jean E.; And Others

1989-01-01

Evaluated ability of self-regulation and emotional-drive theories to explain effects of informational intervention entailing objective descriptions of experience on outcomes of coping with radiation therapy among 84 men with prostate cancer. Consistent with self-regulation theory, similarity between expectations and experience and degree of…

Radiation therapy in adenoid-cystic carcinoma

SciTech Connect

Vikram, B.; Strong, E.W.; Shah, J.P.

1984-02-01

Between 1949-1977, 74 patients with adenoid-cystic carcinoma of various head and neck sites were treated by radiation therapy at Memorial Sloan-Kettering Cancer Center. Radiation therapy alone was employed in 49 patients for recurrent, unresectable disease, and in 25 patients it was given as an adjunct to surgical resection. Among the 49 patients treated with radiation therapy alone, tumor regression was seen in 47 (96%). However, 44 of the 47 (93.5%) subsequently relapsed locally. Relapse occurred within 18 months in one-half of the patients and within 5 years in all of them. Of the 25 patients who received adjunctive radiation therapymore » about one-half relapsed locally within five years. There were 9 patients in this group, however, whose field size exceeded 8x8 cm and the dose of radiation also exceeded 4500 rad: 88% of these patients remained relapse-free at 5 years, compared with only 22% of the other 16 whose dose, or field size, or both, were inadequate by comparison. These data suggest that when irradiation is employed for advanced, inoperable adenoid-cystic carcinoma, it offers useful palliation but is rarely, if ever, curative. Postoperative irradiation, on the other hand, might improve the local control and the survival in patients with operable adenoid-cystic carcinoma who are at high risk for relapse, but only if the field size and the dose are adequate.« less

RADIATION THERAPY IN NEOPLASTIC DISEASE

SciTech Connect

Agnew, C.H.

1962-11-01

Recent innovations in radiotherapy of various forms of cancer are reviewed, and new techniques for treating radiation sickness and injury are outlined. When larger areas of skin are treated with high dosage levels, the erythematous reaction may regress to a wet reaction with denudation. Aqueous 1% gentian violet produces a protective cover which may be soaked off two or three times daily,. followed by a new application by nebulizer or cotton applicator. It is most important to prevent additional trauma. This skin reaction will heal in about two weeks, depending upon the area and depth of involvement. Atrophic dry areasmore » should be protected from irritation. Zinc oxide paste provides an economic protection; however, large areas exhibiting atrophy and ectasia may ulcerate repeatedly. If there has been much vascular damage, adequate excision and skin grafting will probably be necessary. Careful attention must be given to the possibility of metaplasia and transformation into squamous cell carcinoma. The epithelial lining of the oropharynx and esophagas, when included in treatment fields, may develop mucositis near the end of treatment, but the peak reaction usually develops after treatment is completed. This may be easily observed in the oropharynx as a pseudomembranous reaction which looks very much like a monilia infection. This temporary reaction will not require intensive treatment and will respond to warm, normal saline irrigation. The mucous membrane reaction of the esophagus usually develops after approximates 4000 r. Thus, near the end of the 4th wk of treatment, complaints of difficulty in swallowing are expected. There is no effective treatment. Fluoroscopic examination usually does not show a detectable abnormality. The peak reaction may occur 10 days after treatment is completed, and then gradually subsides during the next three weeks. For relief from nausea and vomiting, antiemetics, vitamin B preparations, and antihistamines may be used. Yeast

Clinical applications of image guided-intensity modulated radiation therapy (IG-IMRT) for conformal avoidance of normal tissue

NASA Astrophysics Data System (ADS)

Gutierrez, Alonso Navar

2007-12-01

Recent improvements in imaging technology and radiation delivery have led to the development of advanced treatment techniques in radiotherapy which have opened the door for novel therapeutic approaches to improve the efficacy of radiation cancer treatments. Among these advances is image-guided, intensity modulated radiation therapy (IG-IMRT), in which imaging is incorporated to aid in inter-/intra-fractional target localization and to ensure accurate delivery of precise and highly conformal dose distributions. In principle, clinical implementation of IG-IMRT should improve normal tissue sparing and permit effective biological dose escalation thus widening the radiation therapeutic window and lead to increases in survival through improved local control of primary neoplastic diseases. Details of the development of three clinical applications made possible solely with IG-IMRT radiation delivery techniques are presented: (1) Laparoscopically implanted tissue expander radiotherapy (LITE-RT) has been developed to enhance conformal avoidance of normal tissue during the treatment of intra-abdominopelvic cancers. LITE-RT functions by geometrically displacing surrounding normal tissue and isolating the target volume through the interfractional inflation of a custom-shaped tissue expander throughout the course of treatment. (2) The unique delivery geometry of helical tomotherapy, a novel form of IG-IMRT, enables the delivery of composite treatment plan m which whole brain radiotherapy (WBRT) with hippocampal avoidance, hypothesized to reduce the risk of memory function decline and improve the patient's quality of life, and simultaneously integrated boost to multiple brain metastases to improve intracranial tumor control is achieved. (3) Escalation of biological dose to targets through integrated, selective subvolume boosts have been shown to efficiently increase tumor dose without significantly increasing normal tissue dose. Helical tomotherapy was used to investigate the

Protons -- The Future of Radiation Therapy?

NASA Astrophysics Data System (ADS)

Avery, Steven

2007-03-01

Cancer is the 2^nd highest cause of death in the United States. The challenges of controlling this disease remain more difficult as the population lives longer. Proton therapy offers another choice in the management of cancer care. Proton therapy has existed since the late 1950s and the first hospital based center in the United States opened in 1990. Since that time four hospital based proton centers are treating patients with other centers either under construction or under consideration. This talk will focus on an introduction to proton therapy: it's medical advantages over current treatment modalities, accelerators and beam delivery systems, applications to clinical radiation oncology and the future outlook for proton therapy.

Radiation Enterocolitis Requiring Surgery in Patients With Gynecological Malignancies

SciTech Connect

Iraha, Shiro; Ogawa, Kazuhiko; Moromizato, Hidehiko

Purpose: To identify the characteristics, risk factors, and clinical outcomes of radiation enterocolitis requiring surgery in patients with gynecologic malignancies. Methods and Materials: The records of 1,349 patients treated with pelvic radiotherapy were retrospectively reviewed. The majority of the patients (88%) were treated with 50 Gy or 50.4 Gy pelvic irradiation in conventional fractionations with anteroposterior fields. Results: Forty-eight patients (3.6%) developed radiation enterocolitis requiring surgery. Terminal ileum was the most frequent site (50%) and most of the lesions had stenosis or perforation. On univariate analysis, previous abdominopelvic surgery, diabetes mellitus (DM), smoking and primary site had an impact onmore » the complications, and on multivariate analysis, abdominopelvic surgery, DM, and smoking were independent predictors of the complications requiring surgery. After the surgical intervention, the frequency of Grade 2 or more bleeding was significantly lower in patients treated with intestinal resection in addition to decompression than those treated with intestinal decompression alone. Conclusions: Severe radiation enterocolitis requiring surgery usually occurred at the terminal ileum and was strongly correlated with previous abdominopelvic surgery, DM, and smoking. Concerning the management, liberal resection of the affected bowel appears to be the preferable therapy.« less

START: an advanced radiation therapy information system.

PubMed

Cocco, A; Valentini, V; Balducci, M; Mantello, G

1996-01-01

START is an advanced radiation therapy information system (RTIS) which connects direct information technology present in the devices with indirect information technology for clinical, administrative, information management integrated with the hospital information system (HIS). The following objectives are pursued: to support decision making in treatment planning and functional and information integration with the rest of the hospital; to enhance organizational efficiency of a Radiation Therapy Department; to facilitate the statistical evaluation of clinical data and managerial performance assessment; to ensure the safety and confidentiality of used data. For its development a working method based on the involvement of all operators of the Radiation Therapy Department, was applied. Its introduction in the work activity was gradual, trying to reuse and integrate the existing information applications. The START information flow identifies four major phases: admission, visit of admission, planning, therapy. The system main functionalities available to the radiotherapist are: clinical history/medical report linking function; folder function; planning function; tracking function; electronic mail and banner function; statistical function; management function. Functions available to the radiotherapy technician are: the room daily list function; management function: to the nurse the following functions are available: patient directing function; management function. START is a departmental client (pc-windows)-server (unix) developed on an integrated database of all information of interest (clinical, organizational and administrative) coherent with the standard and with a modular architecture which can evolve with additional functionalities in subsequent times. For a more thorough evaluation of its impact on the daily activity of a radiation therapy facility, a prolonged clinical validation is in progress.

21 CFR 892.5840 - Radiation therapy simulation system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Radiation therapy simulation system. 892.5840... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5840 Radiation therapy simulation system. (a) Identification. A radiation therapy simulation system is a fluoroscopic or radiographic x-ray...

21 CFR 892.5840 - Radiation therapy simulation system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Radiation therapy simulation system. 892.5840... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5840 Radiation therapy simulation system. (a) Identification. A radiation therapy simulation system is a fluoroscopic or radiographic x-ray...

Radiation therapy: age-related macular degeneration.

PubMed

Mendez, Carlos A Medina; Ehlers, Justis P

2013-01-01

Age-related macular degeneration (AMD) is the leading cause of severe irreversible vision loss in patients over the age of 50 years in the developed world. Neovascular AMD (NVAMD) is responsible for 90% of the cases with severe visual loss. In the last decade, the treatment paradigm for NVAMD has been transformed by the advent of anti-vascular endothelial growth factor therapy. Despite the excellent results of anti-vascular endothelial growth factor therapy, frequent injections remain a necessity for most patients. The burden of these frequent visits as well as the cumulative risks of indefinite intravitreal injections demand continued pursuit of more enduring therapy that provides similar functional results. Radiotherapy has been studied for two decades as a potential therapy for NVAMD. Because of its antiangiogenic properties, radiation therapy remains a promising potential adjunctive resource for the treatment of choroidal neovascularization secondary to NVAMD. This review considers the past, present and future of radiation as a treatment or combination treatment of NVAMD. Copyright © 2013 S. Karger AG, Basel.

DOE Research Contributions to Radiation and Cancer Therapy

Science.gov Websites

dropdown arrow Site Map A-Z Index Menu Synopsis DOE Research Contributions to Radiation and Cancer Therapy research has made many contributions to radiation and cancer therapy, including PEREGRINE and Boron Neutron planning radiation treatment for cancer patients. About 90 percent of radiation treatment patients receive

Fiber-optic dosimeters for radiation therapy

NASA Astrophysics Data System (ADS)

Li, Enbang; Archer, James

2017-10-01

According to the figures provided by the World Health Organization, cancer is a leading cause of death worldwide, accounting for 8.8 million deaths in 2015. Radiation therapy, which uses x-rays to destroy or injure cancer cells, has become one of the most important modalities to treat the primary cancer or advanced cancer. The newly developed microbeam radiation therapy (MRT), which uses highly collimated, quasi-parallel arrays of x-ray microbeams (typically 50 μm wide and separated by 400 μm) produced by synchrotron sources, represents a new paradigm in radiotherapy and has shown great promise in pre-clinical studies on different animal models. Measurements of the absorbed dose distribution of microbeams are vitally important for clinical acceptance of MRT and for developing quality assurance systems for MRT, hence are a challenging and important task for radiation dosimetry. On the other hand, during the traditional LINAC based radiotherapy and breast cancer brachytherapy, skin dose measurements and treatment planning also require a high spatial resolution, tissue equivalent, on-line dosimeter that is both economical and highly reliable. Such a dosimeter currently does not exist and remains a challenge in the development of radiation dosimetry. High resolution, water equivalent, optical and passive x-ray dosimeters have been developed and constructed by using plastic scintillators and optical fibers. The dosimeters have peak edge-on spatial resolutions ranging from 50 to 500 microns in one dimension, with a 10 micron resolution dosimeter under development. The developed fiber-optic dosimeters have been test with both LINAC and synchrotron x-ray beams. This work demonstrates that water-equivalent and high spatial resolution radiation detection can be achieved with scintillators and optical fiber systems. Among other advantages, the developed fiber-optic probes are also passive, energy independent, and radiation hard.

Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy

SciTech Connect

Choi, Seo-Hyun; Nam, Jae-Kyung; Jang, Junho

Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-β release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm{sup 3} increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versusmore » radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy. - Highlights: • Radiation changes tumor endothelial cells to fibroblasts. • Radio-resistant tumors contain collagen deposits, especially in tumor vessels. • Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy. • Pirfenidone reduces radiation-induced collagen deposits in tumors.« less

Methods for implementing microbeam radiation therapy

DOEpatents

Dilmanian, F. Avraham; Morris, Gerard M.; Hainfeld, James F.

2007-03-20

A method of performing radiation therapy includes delivering a therapeutic dose such as X-ray only to a target (e.g., tumor) with continuous broad beam (or in-effect continuous) using arrays of parallel planes of radiation (microbeams/microplanar beams). Microbeams spare normal tissues, and when interlaced at a tumor, form a broad-beam for tumor ablation. Bidirectional interlaced microbeam radiation therapy (BIMRT) uses two orthogonal arrays with inter-beam spacing equal to beam thickness. Multidirectional interlaced MRT (MIMRT) includes irradiations of arrays from several angles, which interleave at the target. Contrast agents, such as tungsten and gold, are administered to preferentially increase the target dose relative to the dose in normal tissue. Lighter elements, such as iodine and gadolinium, are used as scattering agents in conjunction with non-interleaving geometries of array(s) (e.g., unidirectional or cross-fired (intersecting) to generate a broad beam effect only within the target by preferentially increasing the valley dose within the tumor.

Patient- and cohort-specific dose and risk estimation for abdominopelvic CT: a study based on 100 patients

NASA Astrophysics Data System (ADS)

Tian, Xiaoyu; Li, Xiang; Segars, W. Paul; Frush, Donald P.; Samei, Ehsan

2012-03-01

The purpose of this work was twofold: (a) to estimate patient- and cohort-specific radiation dose and cancer risk index for abdominopelvic computer tomography (CT) scans; (b) to evaluate the effects of patient anatomical characteristics (size, age, and gender) and CT scanner model on dose and risk conversion coefficients. The study included 100 patient models (42 pediatric models, 58 adult models) and multi-detector array CT scanners from two commercial manufacturers (LightSpeed VCT, GE Healthcare; SOMATOM Definition Flash, Siemens Healthcare). A previously-validated Monte Carlo program was used to simulate organ dose for each patient model and each scanner, from which DLP-normalized-effective dose (k factor) and DLP-normalized-risk index values (q factor) were derived. The k factor showed exponential decrease with increasing patient size. For a given gender, q factor showed exponential decrease with both increasing patient size and patient age. The discrepancies in k and q factors across scanners were on average 8% and 15%, respectively. This study demonstrates the feasibility of estimating patient-specific organ dose and cohort-specific effective dose and risk index in abdominopelvic CT requiring only the knowledge of patient size, gender, and age.

What to Know about External Beam Radiation Therapy

MedlinePlus

... Radiation Therapy: What To Know About External Beam Radiation Therapy Before treatment starts: You will meet with a doctor or ... and show the therapist where to aim the radiation. When you go for treatment: ■ Don’t have powder, deodorant, Band-Aids ® , or ...

Particle Radiation Therapy for Gastrointestinal Malignancies

PubMed Central

Meyer, Jeffrey J.; Willett, Christopher G.

2007-01-01

Treatment-related toxicity is common in the radiotherapeutic management of cancers of the gastrointestinal tract. These toxicities can diminish treatment efficacy by necessitating treatment breaks, limiting the radiation dose that can be delivered, and hindering concomitant use of chemotherapy and targeted drug agents. Many efforts have focused on widening the gap between the likelihood of tumor control and the likelihood of toxicities associated with radiation. Use of particles that exhibit a Bragg peak phenomenon in their interactions with tissue, such as protons, heavier ions like carbon ions, and pions, is one means of concentrating radiation dose in tumors and away from normal tissues. Neutron beams have also been used in the treatment of gastrointestinal cancers in an effort to take advantage of their potent biologic effects. This report reviews basic particle radiation physics and biology, as well as the clinical experience with protons, heavier ions, pions, and neutrons in the treatment of various gastrointestinal malignancies. Potential future directions in clinical research with particle therapy are discussed. PMID:19360149

An evaluation of the use of oral contrast media in abdominopelvic CT.

PubMed

Buttigieg, Erica Lauren; Grima, Karen Borg; Cortis, Kelvin; Soler, Sandro Galea; Zarb, Francis

2014-11-01

To evaluate the diagnostic efficacy of different oral contrast media (OCM) for abdominopelvic CT examinations performed for follow-up general oncological indications. The objectives were to establish anatomical image quality criteria for abdominopelvic CT; use these criteria to evaluate and compare image quality using positive OCM, neutral OCM and no OCM; and evaluate possible benefits for the medical imaging department. Forty-six adult patients attending a follow-up abdominopelvic CT for general oncological indications and who had a previous abdominopelvic CT with positive OCM (n = 46) were recruited and prospectively placed into either the water (n = 25) or no OCM (n = 21) group. Three radiologists performed absolute visual grading analysis (VGA) to assess image quality by grading the fulfilment of 24 anatomical image quality criteria. Visual grading characteristics (VGC) analysis of the data showed comparable image quality with regards to reproduction of abdominal structures, bowel discrimination, presence of artefacts, and visualization of the amount of intra-abdominal fat for the three OCM protocols. All three OCM protocols provided similar image quality for follow-up abdominopelvic CT for general oncological indications. • Positive oral contrast media are routinely used for abdominopelvic multidetector computed tomography • Experimental study comparing image quality using three different oral contrast materials • Three different oral contrast materials result in comparable CT image quality • Benefits for patients and medical imaging department.

Mapping the literature of radiation therapy

PubMed Central

Delwiche, Frances A.

2013-01-01

Objective: This study characterizes the literature of the radiation therapy profession, identifies the journals most frequently cited by authors writing in this discipline, and determines the level of coverage of these journals by major bibliographic indexes. Method: Cited references from three discipline-specific source journals were analyzed according to the Mapping the Literature of Allied Health Project Protocol of the Nursing and Allied Health Resources Section of the Medical Library Association. Bradford's Law of Scattering was applied to all journal references to identify the most frequently cited journal titles. Results: Journal references constituted 77.8% of the total, with books, government documents, Internet sites, and miscellaneous sources making up the remainder. Although a total of 908 journal titles were cited overall, approximately one-third of the journal citations came from just 11 journals. MEDLINE and Scopus provided the most comprehensive indexing of the journal titles in Zones 1 and 2. The source journals were indexed only by CINAHL and Scopus. Conclusion: The knowledgebase of radiation therapy draws heavily from the fields of oncology, radiology, medical physics, and nursing. Discipline-specific publications are not currently well covered by major indexing services, and those wishing to conduct comprehensive literature searches should search multiple resources. PMID:23646027

Mapping the literature of radiation therapy.

PubMed

Delwiche, Frances A

2013-04-01

This study characterizes the literature of the radiation therapy profession, identifies the journals most frequently cited by authors writing in this discipline, and determines the level of coverage of these journals by major bibliographic indexes. Cited references from three discipline-specific source journals were analyzed according to the Mapping the Literature of Allied Health Project Protocol of the Nursing and Allied Health Resources Section of the Medical Library Association. Bradford's Law of Scattering was applied to all journal references to identify the most frequently cited journal titles. Journal references constituted 77.8% of the total, with books, government documents, Internet sites, and miscellaneous sources making up the remainder. Although a total of 908 journal titles were cited overall, approximately one-third of the journal citations came from just 11 journals. MEDLINE and Scopus provided the most comprehensive indexing of the journal titles in Zones 1 and 2. The source journals were indexed only by CINAHL and Scopus. The knowledgebase of radiation therapy draws heavily from the fields of oncology, radiology, medical physics, and nursing. Discipline-specific publications are not currently well covered by major indexing services, and those wishing to conduct comprehensive literature searches should search multiple resources.

Better Efficacy of Synchrotron Spatially Microfractionated Radiation Therapy Than Uniform Radiation Therapy on Glioma.

PubMed

Bouchet, Audrey; Bräuer-Krisch, Elke; Prezado, Yolanda; El Atifi, Michèle; Rogalev, Léonid; Le Clec'h, Céline; Laissue, Jean Albert; Pelletier, Laurent; Le Duc, Géraldine

2016-08-01

Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control and on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses. Copyright © 2016 Elsevier Inc. All rights reserved.

Better Efficacy of Synchrotron Spatially Microfractionated Radiation Therapy Than Uniform Radiation Therapy on Glioma

SciTech Connect

Bouchet, Audrey, E-mail: audrey.m.bouchet@gmail.com; Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble; Bräuer-Krisch, Elke

Purpose: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. Methods and Materials: Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control andmore » on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. Results: MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. Conclusions: These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses.« less

Film Dosimetry for Intensity Modulated Radiation Therapy

NASA Astrophysics Data System (ADS)

Benites-Rengifo, J.; Martínez-Dávalos, A.; Celis, M.; Lárraga, J.

2004-09-01

Intensity Modulated Radiation Therapy (IMRT) is an oncology treatment technique that employs non-uniform beam intensities to deliver highly conformal radiation to the targets while minimizing doses to normal tissues and critical organs. A key element for a successful clinical implementation of IMRT is establishing a dosimetric verification process that can ensure that delivered doses are consistent with calculated ones for each patient. To this end we are developing a fast quality control procedure, based on film dosimetry techniques, to be applied to the 6 MV Novalis linear accelerator for IMRT of the Instituto Nacional de Neurología y Neurocirugía (INNN) in Mexico City. The procedure includes measurements of individual fluence maps for a limited number of fields and dose distributions in 3D using extended dose-range radiographic film. However, the film response to radiation might depend on depth, energy and field size, and therefore compromise the accuracy of measurements. In this work we present a study of the dependence of Kodak EDR2 film's response on the depth, field size and energy, compared with those of Kodak XV2 film. The first aim is to devise a fast and accurate method to determine the calibration curve of film (optical density vs. doses) commonly called a sensitometric curve. This was accomplished by using three types of irradiation techniques: Step-and-shoot, dynamic and static fields.

Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy

SciTech Connect

Hess, Clayton B.; Thompson, Holly M.; Benedict, Stanley H.

Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning—a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and,more » because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of �

The changing role of accelerators in radiation therapy

SciTech Connect

Hanson, W.F.

Conventional low energy x-rays have been used in radiation therapy since the turn of the century. Van de Graaff and Betatron accelerators changed the complexion of radiation therapy in the mid 1940's by providing significantly deeper penetrating photon beams and also providing therapeutic quality electron beams. The development of Cobalt-60 teletherapy in the mid 1950's suppressed the role of accelerators in radiation therapy for nearly 20 years. However, with the development of reliable isocentric rotating linear accelerators, accelerators are rapidly becoming the most popular conventional therapy devices. Following unfavorable clinical results with fast neutron therapy in the late 1930's andmore » early 1940's, the role of cyclotron produced fast neutrons is presently experiencing a renewal in radiation therapy. Several facilities are also experimenting with heavy charged particle beams for therapy.« less

Radiation therapy - what to ask your doctor

MedlinePlus

... tumor Non-Hodgkin lymphoma Prostate cancer Testicular cancer Patient Instructions Abdominal radiation - discharge Bleeding during cancer treatment Brain radiation - discharge Breast radiation - discharge Chest radiation - discharge Dry mouth during ...

PET/CT in Radiation Therapy Planning.

PubMed

Specht, Lena; Berthelsen, Anne Kiil

2018-01-01

Radiation therapy (RT) is an important component of the management of lymphoma patients. Most lymphomas are metabolically active and accumulate 18 F-fluorodeoxyglucose (FDG). Positron emission tomography with computer tomography (PET/CT) imaging using FDG is used routinely in staging and treatment evaluation. FDG-PET/CT imaging is now also used routinely for contouring the target for RT, and has been shown to change the irradiated volume significantly compared with CT imaging alone. Modern advanced imaging techniques with image fusion and motion management in combination with modern highly conformal RT techniques have increased the precision of RT, and have made it possible to reduce dramatically the risks of long-term side effects of treatment while maintaining the high cure rates for these diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Radiation therapy for duct carcinoma in situ: who needs radiation therapy, who doesn't?

PubMed

McCormick, Beryl

2013-08-01

Duct carcinoma in situ (DCIS) is a common but non-life-threatening breast cancer. Four large prospective randomized trials comparing radiation therapy (RT) with none after breast-conservation surgery have all concluded that the use of RT reduces the risk of a local recurrence (LR) in the ipsilateral breast by at least 50%. More information is needed to assess the role of antiestrogen therapy when RT is not given. When markers are validated to predict which patients will have an invasive LR versus another DCIS or no LR, it is hoped that the discussion with the patient will clarify the situation further. Copyright © 2013 Elsevier Inc. All rights reserved.

Ghrelin as a Novel Therapy for Radiation Combined Injury

PubMed Central

Jacob, Asha; Shah, Kavin G; Wu, Rongqian; Wang, Ping

2010-01-01

The threat of nuclear terrorism has led to growing worldwide concern about exposure to radiation. Acute radiation syndrome, or radiation sickness, develops after whole-body or a partial-body irradiation with a high dose of radiation. In the terrorist radiation exposure scenario, however, radiation victims likely suffer from additional injuries such as trauma, burns, wounds or sepsis. Thus, high-dose radiation injuries and appropriate therapeutic interventions must be studied. Despite advances in our understanding of the pathophysiology of radiation injury, very little information is available on the therapeutic approaches to radiation combined injury. In this review, we describe briefly the pathological consequences of ionizing radiation and provide an overview of the animal models of radiation combined injury. We highlight the combined radiation and sepsis model we recently established and suggest the use of ghrelin, a novel gastrointestinal hormone, as a potential therapy for radiation combined injury. PMID:20101281

Frequency of whole breast radiation therapy after intraoperative radiation therapy due to criteria identified by lumpectomy.

PubMed

Mellon, Eric A; Orman, Amber; Joya, Luis E; Montejo, Michael E; Laronga, Christine; Hoover, Susan J; Lee, M Catherine; Khakpour, Nazanin; Kubal, Pamela F; Diaz, Roberto

For selected early breast cancers, intraoperative radiation therapy (IORT) at the time of lumpectomy can be an efficient alternative to fractionated whole breast radiation therapy (WBRT). However, some patients are later recommended WBRT after IORT due to surgical pathologic findings. To understand risk factor identification rates triggering WBRT recommendation, we analyzed adverse prognostic features based on multiple international criteria for suitability for accelerated partial breast irradiation. We performed a single-institution retrospective review of all 200 nonrecurrent invasive breast carcinomas that received IORT in 20 Gy to the tumor cavity using a 50 kV photon applicator between January 2011 and December 2015. IORT eligibility was based on the 2009 accelerated partial breast irradiation Consensus Statement from the American Society for Radiation Oncology (ASTRO). IORT was offered as the sole radiation modality to patients meeting 0-1 "cautionary" and no "unsuitable" criteria before lumpectomy. WBRT was recommended after IORT when 2+ cautionary and/or 1+ unsuitable criteria were met after accounting for resection pathology. We recalculated WBRT recommendation rates using initial and reresection margins for ASTRO consensus, Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology recommendations, and TARGeted Intraoperative radioTherapy vs. Postoperative Radiotherapy trial "prepathology" stratum protocol. Depending on the selection criteria chosen, rates of WBRT recommendation can vary from 4.5% to 33%. WBRT recommendation rates of 30-33% after lumpectomy and IORT are observed when the WBRT indication is a single ASTRO cautionary/unsuitable, Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology intermediate/high-risk criterion, or TARGeted Intraoperative radioTherapy vs. postoperative radiotherapy trial protocol recommendation. Alternatively, allowing for re-excision to clear margins

Online Magnetic Resonance Image Guided Adaptive Radiation Therapy: First Clinical Applications

SciTech Connect

Acharya, Sahaja; Fischer-Valuck, Benjamin W.; Kashani, Rojano

Purpose: To demonstrate the feasibility of online adaptive magnetic resonance (MR) image guided radiation therapy (MR-IGRT) through reporting of our initial clinical experience and workflow considerations. Methods and Materials: The first clinically deployed online adaptive MR-IGRT system consisted of a split 0.35T MR scanner straddling a ring gantry with 3 multileaf collimator-equipped {sup 60}Co heads. The unit is supported by a Monte Carlo–based treatment planning system that allows real-time adaptive planning with the patient on the table. All patients undergo computed tomography and MR imaging (MRI) simulation for initial treatment planning. A volumetric MRI scan is acquired for each patient atmore » the daily treatment setup. Deformable registration is performed using the planning computed tomography data set, which allows for the transfer of the initial contours and the electron density map to the daily MRI scan. The deformed electron density map is then used to recalculate the original plan on the daily MRI scan for physician evaluation. Recontouring and plan reoptimization are performed when required, and patient-specific quality assurance (QA) is performed using an independent in-house software system. Results: The first online adaptive MR-IGRT treatments consisted of 5 patients with abdominopelvic malignancies. The clinical setting included neoadjuvant colorectal (n=3), unresectable gastric (n=1), and unresectable pheochromocytoma (n=1). Recontouring and reoptimization were deemed necessary for 3 of 5 patients, and the initial plan was deemed sufficient for 2 of the 5 patients. The reasons for plan adaptation included tumor progression or regression and a change in small bowel anatomy. In a subsequently expanded cohort of 170 fractions (20 patients), 52 fractions (30.6%) were reoptimized online, and 92 fractions (54.1%) were treated with an online-adapted or previously adapted plan. The median time for recontouring, reoptimization, and QA was 26�

Cancer and Radiation Therapy: Current Advances and Future Directions

PubMed Central

Baskar, Rajamanickam; Lee, Kuo Ann; Yeo, Richard; Yeoh, Kheng-Wei

2012-01-01

In recent years remarkable progress has been made towards the understanding of proposed hallmarks of cancer development and treatment. However with its increasing incidence, the clinical management of cancer continues to be a challenge for the 21st century. Treatment modalities comprise of radiation therapy, surgery, chemotherapy, immunotherapy and hormonal therapy. Radiation therapy remains an important component of cancer treatment with approximately 50% of all cancer patients receiving radiation therapy during their course of illness; it contributes towards 40% of curative treatment for cancer. The main goal of radiation therapy is to deprive cancer cells of their multiplication (cell division) potential. Celebrating a century of advances since Marie Curie won her second Nobel Prize for her research into radium, 2011 has been designated the Year of Radiation therapy in the UK. Over the last 100 years, ongoing advances in the techniques of radiation treatment and progress made in understanding the biology of cancer cell responses to radiation will endeavor to increase the survival and reduce treatment side effects for cancer patients. In this review, principles, application and advances in radiation therapy with their biological end points are discussed. PMID:22408567

Cancer and radiation therapy: current advances and future directions.

PubMed

Baskar, Rajamanickam; Lee, Kuo Ann; Yeo, Richard; Yeoh, Kheng-Wei

2012-01-01

In recent years remarkable progress has been made towards the understanding of proposed hallmarks of cancer development and treatment. However with its increasing incidence, the clinical management of cancer continues to be a challenge for the 21st century. Treatment modalities comprise of radiation therapy, surgery, chemotherapy, immunotherapy and hormonal therapy. Radiation therapy remains an important component of cancer treatment with approximately 50% of all cancer patients receiving radiation therapy during their course of illness; it contributes towards 40% of curative treatment for cancer. The main goal of radiation therapy is to deprive cancer cells of their multiplication (cell division) potential. Celebrating a century of advances since Marie Curie won her second Nobel Prize for her research into radium, 2011 has been designated the Year of Radiation therapy in the UK. Over the last 100 years, ongoing advances in the techniques of radiation treatment and progress made in understanding the biology of cancer cell responses to radiation will endeavor to increase the survival and reduce treatment side effects for cancer patients. In this review, principles, application and advances in radiation therapy with their biological end points are discussed.

Using Oxygen “Microbubbles” To Improve Radiation Therapy

Cancer.gov

Oxygen-carrying “microbubbles” could potentially improve the effectiveness of radiation therapy in the treatment of breast cancer, findings from a study in mice suggest. Using the bubbles along with radiation slowed tumor growth more than radiation alone, as this NCI Cancer Currents post reports.

Radiation therapy in early-stage invasive breast cancer.

PubMed

Lin, Ray; Tripuraneni, Prabhakar

2011-06-01

The treatment of breast cancer involves a multi-disciplinary approach with radiation therapy playing a key role. Breast-conserving surgery has been an option for women with early-stage breast cancer for over two decades now. Multiple randomized trials now have demonstrated the efficacy of breast-conserving surgery followed by radiation therapy. With the advancements in breast imaging and the successful campaign for early detection of breast cancer, more women today are found to have early-stage small breast cancers. Patient factors (breast size, tumor location, history of prior radiation therapy, preexisting conditions such as collagen vascular disease, age, having prosthetically augmented breasts), pathological factors (margin status, tumor size, presence of extensive intraductal component requiring multiple surgical excisions), as well as patient preference are all taken into consideration prior to surgical management of breast cancer. Whole-breast fractionated radiation therapy between 5 and 7 weeks is considered as the standard of care treatment following breast-conserving surgery. However, new radiation treatment strategies have been developed in recent years to provide alternatives to the conventional 5-7 week whole-breast radiation therapy for some patients. Accelerated partial breast radiation therapy (APBI) was introduced because the frequency of breast recurrences outside of the surgical cavity has been shown to be low. This technique allows treatments to be delivered quicker (usually 1 week, twice daily) to a limited volume. Often times, this treatment involves the use of a brachytherapy applicator to be placed into the surgical cavity following breast-conserving surgery. Accelerated hypofractionated whole-breast irradiation may be another faster way to deliver radiation therapy following breast-conserving surgery. This journal article reviews the role of radiation therapy in women with early-stage breast cancer addressing patient selection in breast

Whole-brain hippocampal sparing radiation therapy: Volume-modulated arc therapy vs intensity-modulated radiation therapy case study

SciTech Connect

Lee, Katrina, E-mail: Trinabena23@gmail.com; Lenards, Nishele; Holson, Janice

The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient's neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to themore » hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient's data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain.« less

Whole-brain hippocampal sparing radiation therapy: Volume-modulated arc therapy vs intensity-modulated radiation therapy case study.

PubMed

Lee, Katrina; Lenards, Nishele; Holson, Janice

2016-01-01

The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient׳s neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to the hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient׳s data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Clinical applications of advanced rotational radiation therapy

NASA Astrophysics Data System (ADS)

Nalichowski, Adrian

Purpose: With a fast adoption of emerging technologies, it is critical to fully test and understand its limits and capabilities. In this work we investigate new graphic processing unit (GPU) based treatment planning algorithm and its applications in helical tomotherapy dose delivery. We explore the limits of the system by applying it to challenging clinical cases of total marrow irradiation (TMI) and stereotactic radiosurgery (SRS). We also analyze the feasibility of alternative fractionation schemes for total body irradiation (TBI) and TMI based on reported historical data on lung dose and interstitial pneumonitis (IP) incidence rates. Methods and Materials: An anthropomorphic phantom was used to create TMI plans using the new GPU based treatment planning system and the existing CPU cluster based system. Optimization parameters were selected based on clinically used values for field width, modulation factor and pitch. Treatment plans were also created on Eclipse treatment planning system (Varian Medical Systems Inc, Palo Alto, CA) using volumetric modulated arc therapy (VMAT) for dose delivery on IX treatment unit. A retrospective review was performed of 42 publications that reported IP rates along with lung dose, fractionation regimen, dose rate and chemotherapy. The analysis consisted of nearly thirty two hundred patients and 34 unique radiation regimens. Multivariate logistic regression was performed to determine parameters associated with IP and establish does response function. Results: The results showed very good dosimetric agreement between the GPU and CPU calculated plans. The results from SBRT study show that GPU planning system can maintain 90% target coverage while meeting all the constraints of RTOG 0631 protocol. Beam on time for Tomotherapy and flattening filter free RapidArc was much faster than for Vero or Cyberknife. Retrospective data analysis showed that lung dose and Cyclophosphomide (Cy) are both predictors of IP in TBI/TMI treatments. The

Mesenchymal stem cell therapy for acute radiation syndrome.

PubMed

Fukumoto, Risaku

2016-01-01

Acute radiation syndrome affects military personnel and civilians following the uncontrolled dispersal of radiation, such as that caused by detonation of nuclear devices and inappropriate medical treatments. Therefore, there is a growing need for medical interventions that facilitate the improved recovery of victims and patients. One promising approach may be cell therapy, which, when appropriately implemented, may facilitate recovery from whole body injuries. This editorial highlights the current knowledge regarding the use of mesenchymal stem cells for the treatment of acute radiation syndrome, the benefits and limitations of which are under investigation. Establishing successful therapies for acute radiation syndrome may require using such a therapeutic approach in addition to conventional approaches.

Current advancement in radiation therapy for uterine cervical cancer.

PubMed

Nakano, Takashi; Ohno, Tatsuya; Ishikawa, Hitoshi; Suzuki, Yoshiyuki; Takahashi, Takeo

2010-01-01

Radiation therapy is one of the effective curative treatments for uterine cervical cancer. However poor clinical results for the advanced stages require further improvement of the treatment. Intensive studies on basic and clinical research have been made to improve local control, primarily important for long term survival in radiation therapy. Regarding current advancement in radiation therapy for uterine cervical cancer, the following three major subjects are pointed out; technological development to improve dose distribution by image guided radiation therapy technology, the concomitant anticancer chemotherapy with combination of radiation therapy, and radiation biological assessment of the radiation resistance of tumors. The biological factors overviewed in this article include hypoxia relating factors of HIF-1alpha, SOD, cell cycle parameters of pMI, proliferation factors of Ki67, EGFR, cerbB2, COX-2, cycle regulation proteins p53, p21, apoptosis regulation proteins Bcl2 and Bax and so on. Especially, the variety of these radiation biological factors is important for the selection of an effective treatment method for each patient to maximize the treatment benefit.

Intensity-Modulated Radiation Therapy (IMRT)

MedlinePlus

... specialized training in the field of radiation oncology physics, ensures the linear accelerator delivers the precise radiation ... critical normal structures, as well as the patient's health. Typically, patients are scheduled for IMRT sessions five ...

RADIATION THERAPY COMMUNICATION-REIRRADIATION OF A NASAL TUMOR IN A BRACHYCEPHALIC DOG USING INTENSITY MODULATED RADIATION THERAPY.

PubMed

Rancilio, Nicholas J; Custead, Michelle R; Poulson, Jean M

2016-09-01

A 5-year-old spayed female Shih Tzu was referred for evaluation of a nasal transitional carcinoma. A total lifetime dose of 117 Gy was delivered to the intranasal mass in three courses over nearly 2 years using fractionated intensity modulated radiation therapy (IMRT) to spare normal tissues. Clinically significant late normal tissue side effects were limited to bilaterally diminished tear production. The patient died of metastatic disease progression 694 days after completion of radiation therapy course 1. This case demonstrates that retreatment with radiation therapy to high lifetime doses for recurrent local disease may be well tolerated with IMRT. © 2016 American College of Veterinary Radiology.

Multiple Aperture Radiation Therapy (MART) for Breast Cancer

DTIC Science & Technology

2006-11-01

ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Tianfang Li, Ph.D. 5e. TASK NUMBER Email: tfli@reyes.stanford.edu 5f. WORK UNIT...Radiation Therapy, XIVth International Conference on the Use of Computers in Radiation Therapy (ICCR), Soul , Korea, 2004. CONCLUSIONS Compared with...reconstruction artifacts due to in- sufficient angular sampling and dramatically degrades the image quality.24 Crucial issues in developing 4D CBCT are indeed how

Superficial Radiation Therapy for the Treatment of Nonmelanoma Skin Cancers

PubMed Central

Minni, John; Herold, David

2015-01-01

Superficial radiation therapy has become more widely available to dermatologists. With the advent of more portable machines, it has become more convenient for dermatology practices to employ in an office-based setting. The goal of this paper is to provide a deeper insight into the role of superficial radiation therapy in dermatology practice and to review the current literature surrounding its use in the treatment of both basal and squamous cell carcinomas. PMID:26705443

New technologies in radiation therapy: ensuring patient safety, radiation safety and regulatory issues in radiation oncology.

PubMed

Amols, Howard I

2008-11-01

New technologies such as intensity modulated and image guided radiation therapy, computer controlled linear accelerators, record and verify systems, electronic charts, and digital imaging have revolutionized radiation therapy over the past 10-15 y. Quality assurance (QA) as historically practiced and as recommended in reports such as American Association of Physicists in Medicine Task Groups 40 and 53 needs to be updated to address the increasing complexity and computerization of radiotherapy equipment, and the increased quantity of data defining a treatment plan and treatment delivery. While new technology has reduced the probability of many types of medical events, seeing new types of errors caused by improper use of new technology, communication failures between computers, corrupted or erroneous computer data files, and "software bugs" are now being seen. The increased use of computed tomography, magnetic resonance, and positron emission tomography imaging has become routine for many types of radiotherapy treatment planning, and QA for imaging modalities is beyond the expertise of most radiotherapy physicists. Errors in radiotherapy rarely result solely from hardware failures. More commonly they are a combination of computer and human errors. The increased use of radiosurgery, hypofractionation, more complex intensity modulated treatment plans, image guided radiation therapy, and increasing financial pressures to treat more patients in less time will continue to fuel this reliance on high technology and complex computer software. Clinical practitioners and regulatory agencies are beginning to realize that QA for new technologies is a major challenge and poses dangers different in nature than what are historically familiar.

Music therapy CD creation for initial pediatric radiation therapy: a mixed methods analysis.

PubMed

Barry, Philippa; O'Callaghan, Clare; Wheeler, Greg; Grocke, Denise

2010-01-01

A mixed methods research design was used to investigate the effects of a music therapy CD (MTCD) creation intervention on pediatric oncology patients' distress and coping during their first radiation therapy treatment. The music therapy method involved children creating a music CD using interactive computer-based music software, which was "remixed" by the music therapist-researcher to extend the musical material. Eleven pediatric radiation therapy outpatients aged 6 to 13 years were randomly assigned to either an experimental group, in which they could create a music CD prior to their initial treatment to listen to during radiation therapy, or to a standard care group. Quantitative and qualitative analyses generated multiple perceptions from the pediatric patients, parents, radiation therapy staff, and music therapist-researcher. Ratings of distress during initial radiation therapy treatment were low for all children. The comparison between the two groups found that 67% of the children in the standard care group used social withdrawal as a coping strategy, compared to 0% of the children in the music therapy group; this trend approached significance (p = 0.076). MTCD creation was a fun, engaging, and developmentally appropriate intervention for pediatric patients, which offered a positive experience and aided their use of effective coping strategies to meet the demands of their initial radiation therapy treatment.

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

SciTech Connect

Gay, Hiram A., E-mail: hgay@radonc.wustl.edu; Barthold, H. Joseph; Beth Israel Deaconess Medical Center, Boston, MA

2012-07-01

Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The followingmore » were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.« less

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

PubMed Central

Gay, Hiram A.; Barthold, H. Joseph; O’Meara, Elizabeth; Bosch, Walter R.; El Naqa, Issam; Al-Lozi, Rawan; Rosenthal, Seth A.; Lawton, Colleen; Lee, W. Robert; Sandler, Howard; Zietman, Anthony; Myerson, Robert; Dawson, Laura A.; Willett, Christopher; Kachnic, Lisa A.; Jhingran, Anuja; Portelance, Lorraine; Ryu, Janice; Small, William; Gaffney, David; Viswanathan, Akila N.; Michalski, Jeff M.

2012-01-01

Purpose To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa_R, Adnexa_L, Prostate, SeminalVesc, PenileBulb, Femur_R, and Femur_L. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research. PMID:22483697

TH-F-202-00: MRI for Radiation Therapy

SciTech Connect

NONE

MRI has excellent soft tissue contrast and can provide both anatomical and physiological information. It is becoming increasingly important in radiation therapy for treatment planning, image-guided radiation therapy, and treatment assessment. It is critically important at this time point to educate and update our medical physicists about MRI to prepare for the upcoming surge of MRI applications in radiation therapy. This session will review important basics of MR physics, pulse sequence designs, and current radiotherapy application, as well as showcase exciting new developments in MRI that can be potentially useful in radiation therapy. Learning Objectives: To learn basics of MRmore » physics and understand the differences between various pulse sequences To review current applications of MRI in radiation therapy.To discuss recent MRI advances for future MRI guided radiation therapy Partly supported by NIH (1R21CA165384).; W. Miller, Research supported in part by Siemens Healthcare; G. Li, My clinical research is in part supported by NIH U54CA137788. I have a collaborative research project with Philips Healthcare.; J. Cai, jing cai.« less

Cranial Radiation Therapy and Damage to Hippocampal Neurogenesis

ERIC Educational Resources Information Center

Monje, Michelle

2008-01-01

Cranial radiation therapy is associated with a progressive decline in cognitive function, prominently memory function. Impairment of hippocampal neurogenesis is thought to be an important mechanism underlying this cognitive decline. Recent work has elucidated the mechanisms of radiation-induced failure of neurogenesis. Potential therapeutic…

Once-Daily Radiation Therapy for Inflammatory Breast Cancer

SciTech Connect

Brown, Lindsay; Harmsen, William; Blanchard, Miran

2014-08-01

Purpose: Inflammatory breast cancer (IBC) is a rare and aggressive breast cancer variant treated with multimodality therapy. A variety of approaches intended to escalate the intensity and efficacy of radiation therapy have been reported, including twice-daily radiation therapy, dose escalation, and aggressive use of bolus. Herein, we examine our outcomes for patients treated with once-daily radiation therapy with aggressive bolus utilization, focusing on treatment technique. Methods and Materials: A retrospective review of patients with nonmetastatic IBC treated from January 1, 2000, through December 31, 2010, was performed. Locoregional control (LRC), disease-free survival (DFS), overall survival (OS) and predictors thereof weremore » assessed. Results: Fifty-two women with IBC were identified, 49 (94%) of whom were treated with neoadjuvant chemotherapy. All underwent mastectomy followed by adjuvant radiation therapy. Radiation was delivered in once-daily fractions of 1.8 to 2.25 Gy (median, 2 Gy). Patients were typically treated with daily 1-cm bolus throughout treatment, and 33 (63%) received a subsequent boost to the mastectomy scar. Five-year Kaplan Meier survival estimates for LRC, DFS, and OS were 81%, 56%, and 64%, respectively. Locoregional recurrence was associated with poorer OS (P<.001; hazard ratio [HR], 4.1). Extracapsular extension was associated with worse LRC (P=.02), DFS (P=.007), and OS (P=.002). Age greater than 50 years was associated with better DFS (P=.03). Pathologic complete response was associated with a trend toward improved LRC (P=.06). Conclusions: Once-daily radiation therapy with aggressive use of bolus for IBC results in outcomes consistent with previous reports using various intensified radiation therapy regimens. LRC remains a challenge despite modern systemic therapy. Extracapsular extension, age ≤50 years, and lack of complete response to chemotherapy appear to be associated with worse outcomes. Novel strategies are

Guidelines for respiratory motion management in radiation therapy

PubMed Central

Matsuo, Yukinori; Onishi, Hiroshi; Nakagawa, Keiichi; Nakamura, Mitsuhiro; Ariji, Takaki; Kumazaki, Yu; Shimbo, Munefumi; Tohyama, Naoki; Nishio, Teiji; Okumura, Masahiko; Shirato, Hiroki; Hiraoka, Masahiro

2013-01-01

Respiratory motion management (RMM) systems in external and stereotactic radiotherapies have been developed in the past two decades. Japanese medical service fee regulations introduced reimbursement for RMM from April 2012. Based on thorough discussions among the four academic societies concerned, these Guidelines have been developed to enable staff (radiation oncologists, radiological technologists, medical physicists, radiotherapy quality managers, radiation oncology nurses, and others) to apply RMM to radiation therapy for tumors subject to respiratory motion, safely and appropriately. PMID:23239175

Therapy radiation apparatus for veterinary medicine

SciTech Connect

Parris, D.M.

1987-03-03

A radiation device is described for use in veterinary medicine, for treating exterior and interior portions of animal bodies, comprising: (a) power supply means providing selected voltages; (b) high frequency oscillator means; (c) frequency divider means responsive to the oscillator means, and adapted to control switch means for modulating a voltage supply for at least one non-laser broad band infrared radiation diode providing an expanding beam of radiation; and (d) means for applying at least one one-laser broad band infrared radiation diode to a dermal surface of an animal.

21 CFR 892.5050 - Medical charged-particle radiation therapy system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical charged-particle radiation therapy system...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system...) intended for use in radiation therapy. This generic type of device may include signal analysis and display...

[Risk of second cancer after radiation therapy].

PubMed

Kakinuma, Shizuko; Shimada, Yoshiya

2014-01-01

This review describes the secondary cancer after radiotherapy. Secondary cancer is a great concern for cancer survivors, especially for childhood cancer survivors not only because of their intrinsic high susceptibility to radiation but also because of successful achievement of longer survival. Recent advance of molecular biology reveals unique genomic changes, which distinguish radiation-induced tumors from spontaneous or chemically induced tumors.

Concurrent apatinib and local radiation therapy for advanced gastric cancer

PubMed Central

Zhang, Ming; Deng, Weiye; Cao, Xiaoci; Shi, Xiaoming; Zhao, Huanfen; Duan, Zheping; Lv, Bonan; Liu, Bin

2017-01-01

Abstract Rationale: Apatinib is a novel anti-angiogenic agent targeting vascular endothelial growth factor receptor-2, which is effective in patients with chemotherapy-refractory gastric cancer. There are no reports of concurrent apatinib with local radiation therapy in elderly patients with advanced gastric cancer. Patient concerns and Diagnoses: we present the first published report of a 70-year-old male patient with advanced gastric cancer who received concurrent apatinib and local radiation therapy after failure of oxaliplatin and S-1 chemotherapy. Interventions and Outcomes: The patient received concurrent apatinib and local radiation therapy and was followed up 7 months after therapy without disease progress, 14 months later indicated extensive metastasis and this patient died of pulmonary infection. Lessons: Elderly patients with advanced gastric cancer may benefit from concurrent apatinib with local radiation therapy when chemotherapy is not tolerated or successful. Further studies are needed to investigate the clinical outcomes and toxicities associated with concurrent apatinib and radiation therapy in gastric cancer. PMID:28248891

Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

NASA Astrophysics Data System (ADS)

Bednarz, Bryan; Besemer, Abigail

2017-09-01

The use of radionuclide therapy in the clinical setting is expected to increase significantly over the next decade. There is an important need to understand the radiation-induced second cancer risk associated with these procedures. In this study the radiation-induced cancer risk in five radionuclide therapy patients was investigated. These patients underwent serial SPECT imaging scans following injection as part of a clinical trial testing the efficacy of a 131Iodine-labeled radiopharmaceutical. Using these datasets the committed absorbed doses to multiple sensitive structures were calculated using RAPID, which is a novel Monte Carlo-based 3D dosimetry platform developed for personalized dosimetry. The excess relative risk (ERR) for radiation-induced cancer in these structures was then derived from these dose estimates following the recommendations set forth in the BEIR VII report. The radiation-induced leukemia ERR was highest among all sites considered reaching a maximum value of approximately 4.5. The radiation-induced cancer risk in the kidneys, liver and spleen ranged between 0.3 and 1.3. The lifetime attributable risks (LARs) were also calculated, which ranged from 30 to 1700 cancers per 100,000 persons and were highest for leukemia and the liver for both males and females followed by radiation-induced spleen and kidney cancer. The risks associated with radionuclide therapy are similar to the risk associated with external beam radiation therapy.

Optimization in Radiation Therapy: Applications in Brachytherapy and Intensity Modulated Radiation Therapy

NASA Astrophysics Data System (ADS)

McGeachy, Philip David

Over 50% of cancer patients require radiation therapy (RT). RT is an optimization problem requiring maximization of the radiation damage to the tumor while minimizing the harm to the healthy tissues. This dissertation focuses on two main RT optimization problems: 1) brachytherapy and 2) intensity modulated radiation therapy (IMRT). The brachytherapy research involved solving a non-convex optimization problem by creating an open-source genetic algorithm optimizer to determine the optimal radioactive seed distribution for a given set of patient volumes and constraints, both dosimetric- and implant-based. The optimizer was tested for a set of 45 prostate brachytherapy patients. While all solutions met the clinical standards, they also benchmarked favorably with those generated by a standard commercial solver. Compared to its compatriot, the salient features of the generated solutions were: slightly reduced prostate coverage, lower dose to the urethra and rectum, and a smaller number of needles required for an implant. Historically, IMRT requires modulation of fluence while keeping the photon beam energy fixed. The IMRT-related investigation in this thesis aimed at broadening the solution space by varying photon energy. The problem therefore involved simultaneous optimization of photon beamlet energy and fluence, denoted by XMRT. Formulating the problem as convex, linear programming was applied to obtain solutions for optimal energy-dependent fluences, while achieving all clinical objectives and constraints imposed. Dosimetric advantages of XMRT over single-energy IMRT in the improved sparing of organs at risk (OARs) was demonstrated in simplified phantom studies. The XMRT algorithm was improved to include clinical dose-volume constraints and clinical studies for prostate and head and neck cancer patients were investigated. Compared to IMRT, XMRT provided improved dosimetric benefit in the prostate case, particularly within intermediate- to low-dose regions (≤ 40 Gy

Lung Cancer: Posttreatment Imaging: Radiation Therapy and Imaging Findings.

PubMed

Benveniste, Marcelo F; Welsh, James; Viswanathan, Chitra; Shroff, Girish S; Betancourt Cuellar, Sonia L; Carter, Brett W; Marom, Edith M

2018-05-01

In this review, we discuss the different radiation delivery techniques available to treat non-small cell lung cancer, typical radiologic manifestations of conventional radiotherapy, and different patterns of lung injury and temporal evolution of the newer radiotherapy techniques. More sophisticated techniques include intensity-modulated radiotherapy, stereotactic body radiotherapy, proton therapy, and respiration-correlated computed tomography or 4-dimensional computed tomography for radiotherapy planning. Knowledge of the radiation treatment plan and technique, the completion date of radiotherapy, and the temporal evolution of radiation-induced lung injury is important to identify expected manifestations of radiation-induced lung injury and differentiate them from tumor recurrence or infection. Published by Elsevier Inc.

Integrating Multimodal Radiation Therapy Data into i2b2.

PubMed

Zapletal, Eric; Bibault, Jean-Emmanuel; Giraud, Philippe; Burgun, Anita

2018-04-01

 Clinical data warehouses are now widely used to foster clinical and translational research and the Informatics for Integrating Biology and the Bedside (i2b2) platform has become a de facto standard for storing clinical data in many projects. However, to design predictive models and assist in personalized treatment planning in cancer or radiation oncology, all available patient data need to be integrated into i2b2, including radiation therapy data that are currently not addressed in many existing i2b2 sites.  To use radiation therapy data in projects related to rectal cancer patients, we assessed the feasibility of integrating radiation oncology data into the i2b2 platform.  The Georges Pompidou European Hospital, a hospital from the Assistance Publique - Hôpitaux de Paris group, has developed an i2b2-based clinical data warehouse of various structured and unstructured clinical data for research since 2008. To store and reuse various radiation therapy data-dose details, activities scheduling, and dose-volume histogram (DVH) curves-in this repository, we first extracted raw data by using some reverse engineering techniques and a vendor's application programming interface. Then, we implemented a hybrid storage approach by combining the standard i2b2 "Entity-Attribute-Value" storage mechanism with a "JavaScript Object Notation (JSON) document-based" storage mechanism without modifying the i2b2 core tables. Validation was performed using (1) the Business Objects framework for replicating vendor's application screens showing dose details and activities scheduling data and (2) the R software for displaying the DVH curves.  We developed a pipeline to integrate the radiation therapy data into the Georges Pompidou European Hospital i2b2 instance and evaluated it on a cohort of 262 patients. We were able to use the radiation therapy data on a preliminary use case by fetching the DVH curve data from the clinical data warehouse and displaying them in a R chart. �

Alterations of nutritional status: impact of chemotherapy and radiation therapy

SciTech Connect

Donaldson, S.S.; Lenon, R.A.

1979-05-01

The nutritional status of a cancer patient may be affected by the tumor, the chemotherapy and/or radiation therapy directed against the tumor, and by complications associated with that therapy. Chemotherpay-radiotherapy is not confined exclusively to malignant cell populations; thus, normal tissues may also be affected by the therapy and may contribute to specific nutritional problems. Impaired nutrition due to anorexia, mucositis, nausea, vomiting, and diarrhea may be dependent upon the specific chemotherapeutic agent, dose, or schedule utilized. Similar side effects from radiation therapy depend upon the dose, fractionation, and volume irradiated. When combined modality treatment is given the nutritional consequencesmore » may be magnified. Prospective, randomized clinical trials are underway to investigate the efficacy of nutritional support during chemotherapy-radiotherapy on tolerance to treatment, complications from treatment, and response rates to treatment. Preliminary results demonstrate that the administration of total parenteral nutrition is successful in maintaining weight during radiation therapy and chemotherapy, but that weight loss occurs after discontinuation of nutritional support. Thus, longterm evaluation is mandatory to learn the impact of nutritional support on survival, diease-free survival, and complication rates, as well as on the possible prevention of morbidity associated with aggressive chemotherapy-radiation therapy.« less

Radiation therapy of primary vaginal carcinoma

SciTech Connect

Nori, D.; Hilaris, B.S.; Stanimir, G.

1983-10-01

Primary carcinoma of the vagina is rare, constituting only 1 to 2% of all neoplasms arising in the female genital tract. From 1950-1974, 36 patients with carcinoma of the vagina were treated with radiation at Memorial Sloan-Kettering Cancer Center (MSKCC); 35 (96%) had epidermoid carcinoma and one patient (4%) had adenocarcinoma. These patients were staged according to FIGO. Fourteen patients (39%) were Stage I; six patients (17%) were Stage II; three patients (8%) were Stage III; and 13 patients (36%) were Stage IV. Nine patients (25%) were treated with external radiation and interstitial implant; seven patients (20%) were treated withmore » interstitial implant alone; nine patients (25%) were treated with external radiation alone and 11 patients (30%) with external radiation and intracavitary radiation. The five year NED survival was 71% in Stage I, 66% in Stage II, 33% in Stage III and 0% in Stage IV. This paper discusses radiotherapy management of primary carcinoma of the vagina.« less

Imaging and Data Acquisition in Clinical Trials for Radiation Therapy

SciTech Connect

FitzGerald, Thomas J., E-mail: Thomas.Fitzgerald@umassmed.edu; Bishop-Jodoin, Maryann; Followill, David S.

2016-02-01

Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy qualitymore » assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.« less

Radiation with or without Antiandrogen Therapy in Recurrent Prostate Cancer

PubMed Central

Shipley, W.U.; Seiferheld, W.; Lukka, H.R.; Major, P.P.; Heney, N.M.; Grignon, D.J.; Sartor, O.; Patel, M.P.; Bahary, J.-P.; Zietman, A.L.; Pisansky, T.M.; Zeitzer, K.L.; Lawton, C.A.F.; Feng, F.Y.; Lovett, R.D.; Balogh, A.G.; Souhami, L.; Rosenthal, S.A.; Kerlin, K.J.; Dignam, J.J.; Pugh, S.L.; Sandler, H.M.

2017-01-01

BACKGROUND Salvage radiation therapy is often necessary in men who have undergone radical pros-tatectomy and have evidence of prostate-cancer recurrence signaled by a persistently or recurrently elevated prostate-specific antigen (PSA) level. Whether antiandrogen therapy with radiation therapy will further improve cancer control and prolong overall survival is unknown. METHODS In a double-blind, placebo-controlled trial conducted from 1998 through 2003, we assigned 760 eligible patients who had undergone prostatectomy with a lymphadenectomy and had disease, as assessed on pathological testing, with a tumor stage of T2 (confined to the prostate but with a positive surgical margin) or T3 (with histologic extension beyond the prostatic capsule), no nodal involvement, and a detectable PSA level of 0.2 to 4.0 ng per milliliter to undergo radiation therapy and receive either antiandrogen therapy (24 months of bicalutamide at a dose of 150 mg daily) or daily placebo tablets during and after radiation therapy. The primary end point was the rate of overall survival. RESULTS The median follow-up among the surviving patients was 13 years. The actuarial rate of overall survival at 12 years was 76.3% in the bicalutamide group, as compared with 71.3% in the placebo group (hazard ratio for death, 0.77; 95% confidence interval, 0.59 to 0.99; P=0.04). The 12-year incidence of death from prostate cancer, as assessed by means of central review, was 5.8% in the bicalutamide group, as compared with 13.4% in the placebo group (P<0.001). The cumulative incidence of metastatic prostate cancer at 12 years was 14.5% in the bicalutamide group, as compared with 23.0% in the placebo group (P=0.005). The incidence of late adverse events associated with radiation therapy was similar in the two groups. Gynecomastia was recorded in 69.7% of the patients in the bicalutamide group, as compared with 10.9% of those in the placebo group (P<0.001). CONCLUSIONS The addition of 24 months of antiandrogen

Trial Watch: Immunotherapy plus radiation therapy for oncological indications.

PubMed

Vacchelli, Erika; Bloy, Norma; Aranda, Fernando; Buqué, Aitziber; Cremer, Isabelle; Demaria, Sandra; Eggermont, Alexander; Formenti, Silvia Chiara; Fridman, Wolf Hervé; Fucikova, Jitka; Galon, Jérôme; Spisek, Radek; Tartour, Eric; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

2016-01-01

Malignant cells succumbing to some forms of radiation therapy are particularly immunogenic and hence can initiate a therapeutically relevant adaptive immune response. This reflects the intrinsic antigenicity of malignant cells (which often synthesize a high number of potentially reactive neo-antigens) coupled with the ability of radiation therapy to boost the adjuvanticity of cell death as it stimulates the release of endogenous adjuvants from dying cells. Thus, radiation therapy has been intensively investigated for its capacity to improve the therapeutic profile of several anticancer immunotherapies, including (but not limited to) checkpoint blockers, anticancer vaccines, oncolytic viruses, Toll-like receptor (TLR) agonists, cytokines, and several small molecules with immunostimulatory effects. Here, we summarize recent preclinical and clinical advances in this field of investigation.

Determinants of job satisfaction among radiation therapy faculty.

PubMed

Swafford, Larry G; Legg, Jeffrey S

2009-01-01

Job satisfaction is one of the most significant predictors of employee retention in a variety of occupational settings, including health care and education. A national survey of radiation therapy educators (n = 90) has indicated that respondents are not satisfied with their jobs based on data collected using the Minnesota Satisfaction Questionnaire (MSQ). To predict the factors associated with job satisfaction or dissatisfaction, the authors used a nine-item questionnaire derived from the MSQ. Educators were grouped according to their job satisfaction scores, and multiple discriminant analysis was used to determine which factors were predictive of satisfaction among groups of educators. Statistical results indicate that ability utilization, institutional support, compensation, personnel, and job characteristics were key determinants of job satisfaction among radiation therapy educators. These results may better inform faculty and administration of important factors that can promote job satisfaction and retain faculty in radiation therapy education programs.

Water as neutral oral contrast agent in abdominopelvic CT: comparing effectiveness with Gastrografin in the same patient.

PubMed

Lee, C H; Gu, H Z; Vellayappan, B A; Tan, C H

2016-12-01

Positive oral contrast is no longer deemed necessary for abdominopelvic computed tomography (CT) scans. Studies have shown water to be an equally effective oral contrast agent. However, to our knowledge no study has compared effectiveness between gastrografin and water in the same patient, which will provide a more objective evaluation of the two oral contrast agents. We aim to make a head-to-head comparison of water as neutral oral contrast (OC) against gastrografin as positive OC for abdominopelvic CT scans in the same patient. A retrospective review of 206 abdominopelvic CT scans of 103 patients was performed. The scans were reviewed in consensus by two blinded radiologists. The ability to visualise each abdominopelvic organ, contrastassociated artefacts and small bowel wall delineation, was qualitatively scored on a 5-point scale. Each patient had two sets of scores, one with water and another with gastrografin as OC. Paired scores from the two OCs were evaluated by Wilcoxon signed rank test to determine any significant difference in performance between the two OCs for visualisation of abdominopelvic anatomy on CT. There was significantly better delineation of duodenal wall (p<0.001) and overall visualisation of the duodenum (p=0.011) using water as OC compared to gastrografin. No statistically significant differences were demonstrated between water and gastrografin for visualisation of the rest of the abdominopelvic organs, walldelineation of the rest small bowel and contrast-associated artefacts. Water can be used in place of gastrografin as oral contrast in abdominopelvic CT without compromising visualization of abdominopelvic organs.

The physical basis and future of radiation therapy.

PubMed

Bortfeld, T; Jeraj, R

2011-06-01

The remarkable progress in radiation therapy over the last century has been largely due to our ability to more effectively focus and deliver radiation to the tumour target volume. Physics discoveries and technology inventions have been an important driving force behind this progress. However, there is still plenty of room left for future improvements through physics, for example image guidance and four-dimensional motion management and particle therapy, as well as increased efficiency of more compact and cheaper technologies. Bigger challenges lie ahead of physicists in radiation therapy beyond the dose localisation problem, for example in the areas of biological target definition, improved modelling for normal tissues and tumours, advanced multicriteria and robust optimisation, and continuous incorporation of advanced technologies such as molecular imaging. The success of physics in radiation therapy has been based on the continued "fuelling" of the field with new discoveries and inventions from physics research. A key to the success has been the application of the rigorous scientific method. In spite of the importance of physics research for radiation therapy, too few physicists are currently involved in cutting-edge research. The increased emphasis on more "professionalism" in medical physics will tip the situation even more off balance. To prevent this from happening, we argue that medical physics needs more research positions, and more and better academic programmes. Only with more emphasis on medical physics research will the future of radiation therapy and other physics-related medical specialties look as bright as the past, and medical physics will maintain a status as one of the most exciting fields of applied physics.

The physical basis and future of radiation therapy

PubMed Central

Bortfeld, T; Jeraj, R

2011-01-01

The remarkable progress in radiation therapy over the last century has been largely due to our ability to more effectively focus and deliver radiation to the tumour target volume. Physics discoveries and technology inventions have been an important driving force behind this progress. However, there is still plenty of room left for future improvements through physics, for example image guidance and four-dimensional motion management and particle therapy, as well as increased efficiency of more compact and cheaper technologies. Bigger challenges lie ahead of physicists in radiation therapy beyond the dose localisation problem, for example in the areas of biological target definition, improved modelling for normal tissues and tumours, advanced multicriteria and robust optimisation, and continuous incorporation of advanced technologies such as molecular imaging. The success of physics in radiation therapy has been based on the continued “fuelling” of the field with new discoveries and inventions from physics research. A key to the success has been the application of the rigorous scientific method. In spite of the importance of physics research for radiation therapy, too few physicists are currently involved in cutting-edge research. The increased emphasis on more “professionalism” in medical physics will tip the situation even more off balance. To prevent this from happening, we argue that medical physics needs more research positions, and more and better academic programmes. Only with more emphasis on medical physics research will the future of radiation therapy and other physics-related medical specialties look as bright as the past, and medical physics will maintain a status as one of the most exciting fields of applied physics. PMID:21606068

Synchrotron Radiation Therapy from a Medical Physics point of view

NASA Astrophysics Data System (ADS)

Prezado, Y.; Adam, J. F.; Berkvens, P.; Martinez-Rovira, I.; Fois, G.; Thengumpallil, S.; Edouard, M.; Vautrin, M.; Deman, P.; Bräuer-Krisch, E.; Renier, M.; Elleaume, H.; Estève, F.; Bravin, A.

2010-07-01

Synchrotron radiation (SR) therapy is a promising alternative to treat brain tumors, whose management is limited due to the high morbidity of the surrounding healthy tissues. Several approaches are being explored by using SR at the European Synchrotron Radiation Facility (ESRF), where three techniques are under development Synchrotron Stereotactic Radiation Therapy (SSRT), Microbeam Radiation Therapy (MRT) and Minibeam Radiation Therapy (MBRT). The sucess of the preclinical studies on SSRT and MRT has paved the way to clinical trials currently in preparation at the ESRF. With this aim, different dosimetric aspects from both theoretical and experimental points of view have been assessed. In particular, the definition of safe irradiation protocols, the beam energy providing the best balance between tumor treatment and healthy tissue sparing in MRT and MBRT, the special dosimetric considerations for small field dosimetry, etc will be described. In addition, for the clinical trials, the definition of appropiate dosimetry protocols for patients according to the well established European Medical Physics recommendations will be discussed. Finally, the state of the art of the MBRT technical developments at the ESRF will be presented. In 2006 A. Dilmanian and collaborators proposed the use of thicker microbeams (0.36-0.68 mm). This new type of radiotherapy is the most recently implemented technique at the ESRF and it has been called MBRT. The main advantage of MBRT with respect to MRT is that it does not require high dose rates. Therefore it can be more easily applied and extended outside synchrotron sources in the future.

Hypofractionated radiation therapy for prostate cancer: biologic and technical considerations

PubMed Central

Sanfilippo, Nicholas J; Cooper, Benjamin T

2014-01-01

The optimal radiation schedule for the curative treatment of prostate cancer is not known. The dose-response of tumors and normal tissues to fractionated irradiation can be described according to a parameter called the alpha-beta ratio (α/β). In the past several years numerous reports have been published that suggest that the alpha-beta ratio for prostate cancer may be quite low; between 1 and 3. If this hypothesis is true, then a radiation therapy schedule that employs less frequent and larger fractions, termed hypofractionation, may be more efficacious. Multiple randomized trials have been conducted comparing moderate (less than 5 Gy/day) hypofractionated radiation therapy and standard radiation therapy in men with prostate cancer. In the majority of these studies the moderate hypofractionated arm had equivalent efficacy with a similar or improved side effect profile. One area to use caution may be in patients with compromised (IPSS > 12) urinary function at baseline due to an increase in urinary toxicity observed in patients treated with hypofractionated radiation in one study. Extreme hypofractionation (greater than or equal to 5 Gy/day), is currently being compared in a randomized trial. Early prospectively collected data from multiple institutions demonstrates efficacy and toxicity that compares favorably with historical controls. The cost savings from hypofractionation could be profound on a national level and only increases the necessity of testing hypofractionated treatment schedules. Long term data and future trials will help radiation oncologists determine the ideal fractionation scheme based on cost, efficacy, and toxicity. PMID:25606574

Phenytoin Induced Erythema Multiforme after Cranial Radiation Therapy

PubMed Central

Tekkök, İsmail Hakkı

2015-01-01

The prophylactic use of phenytoin during and after brain surgery and cranial irradiation is a common measure in brain tumor therapy. Phenytoin has been associated with variety of adverse skin reactions including urticaria, erythroderma, erythema multiforme (EM), Stevens-Johnson syndrome, and toxic epidermal necrolysis. EM associated with phenytoin and cranial radiation therapy (EMPACT) is a rare specific entity among patients with brain tumors receiving radiation therapy while on prophylactic anti-convulsive therapy. Herein we report a 41-year-old female patient with left temporal glial tumor who underwent surgery and then received whole brain radiation therapy and chemotherapy. After 24 days of continous prophylactic phenytoin therapy the patient developed minor skin reactions and 2 days later the patient returned with generalized erythamatous and itchy maculopapuler rash involving neck, chest, face, trunk, extremities. There was significant periorbital and perioral edema. Painful mucosal lesions consisting of oral and platal erosions also occurred and prevented oral intake significantly. Phenytoin was discontinued gradually. Systemic admistration of corticosteroids combined with topical usage of steroids for oral lesions resulted in complete resolution of eruptions in 3 weeks. All cutaneous lesions in patients with phenytoin usage with the radiotherapy must be evoluated with suspicion for EM. PMID:26361537

Laser Acceleration of Ions for Radiation Therapy

NASA Astrophysics Data System (ADS)

Tajima, Toshiki; Habs, Dietrich; Yan, Xueqing

Ion beam therapy for cancer has proven to be a successful clinical approach, affording as good a cure as surgery and a higher quality of life. However, the ion beam therapy installation is large and expensive, limiting its availability for public benefit. One of the hurdles is to make the accelerator more compact on the basis of conventional technology. Laser acceleration of ions represents a rapidly developing young field. The prevailing acceleration mechanism (known as target normal sheath acceleration, TNSA), however, shows severe limitations in some key elements. We now witness that a new regime of coherent acceleration of ions by laser (CAIL) has been studied to overcome many of these problems and accelerate protons and carbon ions to high energies with higher efficiencies. Emerging scaling laws indicate possible realization of an ion therapy facility with compact, cost-efficient lasers. Furthermore, dense particle bunches may allow the use of much higher collective fields, reducing the size of beam transport and dump systems. Though ultimate realization of a laser-driven medical facility may take many years, the field is developing fast with many conceptual innovations and technical progress.

18F-FDG PET/CT delayed images with forced diuresis for revaluating abdominopelvic malignancies.

PubMed

Wang, Hui-Chun; Wang, Zhi-Min; Wang, Yu-Bin; Chen, Xiao-Hong; Cui, Lan-Lan

2017-05-01

The aim of this retrospective study was to evaluate the role of delayed images after forced diuresis coupled with oral hydration in abdominopelvic 18 F-FDG PET/CT. Forty-six patients consisting of 17 urological diseases, 9 gynecological tumors, 18 colorectal malignancies, and 2 cancers of unknown primary site were retrospectively analyzed. All patients who presented with indeterminate or equivocal abdominopelvic foci on standard 18 F-FDG PET/CT underwent a delayed abdominopelvic imaging after administration of 20 mg furosemide intravenously and extra water intake of 500 mL. PET/CT images before and after furosemide were compared with each other and their findings correlated with pathology or clinical follow-up (>6 months). On initial PET/CT, the glucose metabolism characters of lesions were disguised by radioactive urine, or some undetermined 18 F-FDG accumulating foci near the urinary tract appeared. While postdiuretic PET/CT demonstrated an excellent urinary tracer washout, and hypermetabolic lesions could be clearly detected and precisely localized in all cases. On the other hand, the suspected active foci caused by potential stagnation of excreted 18 F-FDG in urinary tract were eliminated. The sensitivity, specificity, and accuracy were 94.4% (34/36), 8/10, 91.3% (42/46), respectively. Furthermore, the additional lesions with surrounding invasion or locoregional metastasis were discovered in 8 of 46 (17.4%) patients only by the delayed images, including 2 gynecological and 6 rectal malignancies. Detection of abdominopelvic malignancies can be improved using delayed 18 F-FDG PET/CT images after a diuretic and oral hydration.

Communication skills training for radiation therapists: preparing patients for radiation therapy.

PubMed

Halkett, Georgia; O'Connor, Moira; Aranda, Sanchia; Jefford, Michael; Merchant, Susan; York, Debra; Miller, Lisa; Schofield, Penelope

2016-12-01

Patients sometimes present for radiation therapy with high levels of anxiety. Communication skills training may assist radiation therapists to conduct more effective consultations with patients prior to treatment planning and treatment commencement. The overall aim of our research is to examine the effectiveness of a preparatory programme 'RT Prepare' delivered by radiation therapists to reduce patient psychological distress. The purpose of this manuscript was to describe the communication skills workshops developed for radiation therapists and evaluate participants' feedback. Radiation therapists were invited to participate in two communication skills workshops run on the same day: (1) Consultation skills in radiation therapy and (2) Eliciting and responding to patients' emotional cues. Evaluation forms were completed. Radiation therapists' consultations with patients were then audio-recorded and evaluated prior to providing a follow-up workshop with participants. Nine full day workshops were held. Sixty radiation therapists participated. Positive feedback was received for both workshops with 88% or more participants agreeing or strongly agreeing with all the statements about the different components of the two workshops. Radiation therapists highlighted participating in role play with an actor, discussing issues; receiving feedback; acquiring new skills and knowledge; watching others role play and practicing with checklist were their favourite aspects of the initial workshop. The follow-up workshops provided radiation therapists with feedback on how they identified and addressed patients' psychological concerns; time spent with patients during consultations and the importance of finding private space for consultations. Communication skills training consisting of preparing patients for radiation therapy and eliciting and responding to emotional cues with follow-up workshops has the potential to improve radiation therapists' interactions with patients undergoing

The Application of FLUKA to Dosimetry and Radiation Therapy

NASA Technical Reports Server (NTRS)

Wilson, Thomas L.; Andersen, Victor; Pinsky, Lawrence; Ferrari, Alfredo; Battistoni, Giusenni

2005-01-01

Monte Carlo transport codes like FLUKA are useful for many purposes, and one of those is the simulation of the effects of radiation traversing the human body. In particular, radiation has been used in cancer therapy for a long time, and recently this has been extended to include heavy ion particle beams. The advent of this particular type of therapy has led to the need for increased capabilities in the transport codes used to simulate the detailed nature of the treatment doses to the Y O U S tissues that are encountered. This capability is also of interest to NASA because of the nature of the radiation environment in space.[l] While in space, the crew members bodies are continually being traversed by virtually all forms of radiation. In assessing the risk that this exposure causes, heavy ions are of primary importance. These arise both from the primary external space radiation itself, as well as fragments that result from interactions during the traversal of that radiation through any intervening material including intervening body tissue itself. Thus the capability to characterize the details of the radiation field accurately within a human body subjected to such external 'beams" is of critical importance.

QA in Radiation Therapy: The RPC Perspective

NASA Astrophysics Data System (ADS)

Ibbott, G. S.

2010-11-01

The Radiological Physics Center (RPC) is charged with assuring the consistent delivery of radiation doses to patients on NCI-sponsored clinical trials. To accomplish this, the RPC conducts annual mailed audits of machine calibration, dosimetry audit visits to institutions, reviews of treatment records, and credentialing procedures requiring the irradiation of anthropomorphic phantoms. Through these measurements, the RPC has gained an understanding of the level of quality assurance practiced in this cohort of institutions, and a database of measurements of beam characteristics of a large number of treatment machines. The results of irradiations of phantoms have yielded insight into the delivery of advanced technology treatment procedures.

Radiation therapy in the management of patients with mesothelioma

SciTech Connect

Gordon, W. Jr.; Antman, K.H.; Greenberger, J.S.

The results of radiation therapy in the management of 27 patients with malignant mesothelioma were reviewed. Eight patients were treated with a curative intent combining attempted surgical excision of tumor (thoracic in 6 and peritoneal in 2), aggressive radiation therapy, and combination chemotherapy using an adriamycin-containing regimen. One patient achieved a 2-year disease-free inteval followed by recurrence of tumor above the thoracic irradiation field. This patient was retreated with localized irradiation and is disease-free after 5 years of initial diagnosis. One patient has persistent abdominal disease at 18 months; the other 6 patients suffered local recurrence within 8-13 months ofmore » initiation of treatment. Radiation therapy was used in 19 other patients who received 29 courses for palliation of dyspnea, superior vena cava syndrome, dysphagia, or neurological symptoms of brain metastasis. A palliation index was used to determine the effectiveness of irradiation and revealed that relief of symptoms was complete or substantial in 5 treatment courses, moderately effective in 6 courses and inadequate in 18 treatment courses. Adequate palliation strongly correlated with a dose at or above 4,000 rad in 4 weeks. The management of patients with mesothelioma requires new and innovative approaches to increase the effectiveness of radiation therapy and minimize the significant potential combined toxicity of pulmonary irradiation and adriamycin.« less

3-dimensional beam scanning system for particle radiation therapy

SciTech Connect

Leemann, C.; Alonso, J.; Grunder, H.

1977-03-01

In radiation therapy treatment volumes up to several liters have to be irradiated. Today's charged particle programs use ridge filters, scattering foils, occluding rings collimators and boluses to shape the dose distribution. An alternative approach, scanning of a small diameter beam, is analyzed and tentative systems specifications are derived. Critical components are scheduled for fabrication and testing at LBL.

Factors influencing radiation therapy student clinical placement satisfaction

SciTech Connect

Bridge, Pete; Carmichael, Mary-Ann

Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanismsmore » during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning.« less

Waiting Lists for Radiation Therapy: A Case Study

PubMed Central

2001-01-01

Background Why waiting lists arise and how to address them remains unclear, and an improved understanding of these waiting list "dynamics" could lead to better management. The purpose of this study is to understand how the current shortage in radiation therapy in Ontario developed; the implications of prolonged waits; who is held accountable for managing such delays; and short, intermediate, and long-term solutions. Methods A case study of the radiation therapy shortage in 1998-99 at Princess Margaret Hospital, Toronto, Ontario, Canada. Relevant documents were collected; semi-structured, face-to-face interviews with ten administrators, health care workers, and patients were conducted, audio-taped and transcribed; and relevant meetings were observed. Results The radiation therapy shortage arose from a complex interplay of factors including: rising cancer incidence rates; broadening indications for radiation therapy; human resources management issues; government funding decisions; and responsiveness to previous planning recommendations. Implications of delays include poorer cancer control rates; patient suffering; and strained doctor-patient relationships. An incompatible relationship exists between moral responsibility, borne by government, and legal liability, borne by physicians. Short-term solutions include re-referral to centers with available resources; long-term solutions include training and recruiting health care workers, improving workload standards, increasing compensation, and making changes to the funding formula. Conclusion Human resource planning plays a critical role in the causes and solutions of waiting lists. Waiting lists have harsh implications for patients. Accountability relationships require realignment. PMID:11319944

21 CFR 892.5300 - Medical neutron radiation therapy system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical neutron radiation therapy system. 892.5300 Section 892.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment support, treatment planning computer programs...

21 CFR 892.5750 - Radionuclide radiation therapy system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Radionuclide radiation therapy system. 892.5750 Section 892.5750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... patient's body. This generic type of device may include signal analysis and display equipment, patient and...

21 CFR 892.5840 - Radiation therapy simulation system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Radiation therapy simulation system. 892.5840 Section 892.5840 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... include signal analysis and display equipment, patient and equipment supports, treatment planning computer...

21 CFR 892.5750 - Radionuclide radiation therapy system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Radionuclide radiation therapy system. 892.5750 Section 892.5750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... patient's body. This generic type of device may include signal analysis and display equipment, patient and...

21 CFR 892.5750 - Radionuclide radiation therapy system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide radiation therapy system. 892.5750 Section 892.5750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... patient's body. This generic type of device may include signal analysis and display equipment, patient and...

21 CFR 892.5750 - Radionuclide radiation therapy system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Radionuclide radiation therapy system. 892.5750 Section 892.5750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... patient's body. This generic type of device may include signal analysis and display equipment, patient and...

21 CFR 892.5300 - Medical neutron radiation therapy system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical neutron radiation therapy system. 892.5300 Section 892.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment support, treatment planning computer programs...

21 CFR 892.5300 - Medical neutron radiation therapy system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical neutron radiation therapy system. 892.5300 Section 892.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment support, treatment planning computer programs...

21 CFR 892.5300 - Medical neutron radiation therapy system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical neutron radiation therapy system. 892.5300 Section 892.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment support, treatment planning computer programs...

21 CFR 892.5750 - Radionuclide radiation therapy system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Radionuclide radiation therapy system. 892.5750 Section 892.5750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... patient's body. This generic type of device may include signal analysis and display equipment, patient and...

21 CFR 892.5840 - Radiation therapy simulation system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy simulation system. 892.5840 Section 892.5840 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... include signal analysis and display equipment, patient and equipment supports, treatment planning computer...

21 CFR 892.5300 - Medical neutron radiation therapy system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical neutron radiation therapy system. 892.5300 Section 892.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment support, treatment planning computer programs...

21 CFR 892.5840 - Radiation therapy simulation system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Radiation therapy simulation system. 892.5840 Section 892.5840 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... include signal analysis and display equipment, patient and equipment supports, treatment planning computer...

Factors influencing radiation therapy student clinical placement satisfaction

PubMed Central

Bridge, Pete; Carmichael, Mary-Ann

2014-01-01

Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning. PMID:26229635

BRCA1 Mutation: A Predictive Marker for Radiation Therapy?

SciTech Connect

Kan, Charlene; Zhang, Junran, E-mail: Junran.zhang@case.edu

2015-10-01

DNA repair, in particular, DNA double-strand break (DSB) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells to efficiently repair the damaged DNA. The pathways predominately involved in DSB repair are homologous recombination and classic nonhomologous end-joining, although the alternative NHEJ pathway, a third DSB repair pathway, could also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSB repair pathways. Given that DSBs represent the most biologically significant lesions induced by ionizing radiation and that impaired DSB repairmore » leads to radiation sensitivity, it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy. However, the clinical data have been conflicting and inconclusive. We provide an overview about the current status of the data regarding BRCA1 deficiency and radiation therapy sensitivity in both experimental models and clinical investigations. In addition, we discuss a strategy to potentiate the effects of radiation therapy by poly(ADP-ribose) polymerase inhibitors, the pharmacologic drugs being investigated as monotherapy for the treatment of patients with BRCA1/2 mutations.« less

Use of dimethyl sulfoxide (DMSO) in radiation therapy (in German)

SciTech Connect

Glaser, F.H.

1973-01-01

The present clinical examinstion deals with the possible use of DMSO in rsdiation therapy. DMSO was applied to 30 patients, 8 times in radiogenic subcutaneous fibroses, 13 times in contracted scars and keloids, 3 times in cases of induratio penis plastica, and 6 times as vehicle substsnce for tamor cell sensitization with vitamin A in the radiation therapy of skin metastases sfter mamma carcinoma. The results confirm the value of a DMSO treatment of subcutaneous fibroses following highly dosed percutaneous radiation therapy, especially in cases with a radiological ulcer. In keloids of scars a clear effect could be achieved withoutmore » exceptions also in those csses showing only insufficient regression tendency to a preceded rsdiation therapy. The results of irradiation in cases with I.p.p., however, did not show any convincing improvement by a DMSO treatment. A new field of application is opened for the indiation therapy of recurrences and metastases in the area of the skin by sensitization of these cutaneous tumor infiltrates by vitamin A in connection with DMSO as vehicle substance so that a curative regression can be locally obtained by relatively low radiation doses. (auth)« less

Relating physician's workload with errors during radiation therapy planning.

PubMed

Mazur, Lukasz M; Mosaly, Prithima R; Hoyle, Lesley M; Jones, Ellen L; Chera, Bhishamjit S; Marks, Lawrence B

2014-01-01

To relate subjective workload (WL) levels to errors for routine clinical tasks. Nine physicians (4 faculty and 5 residents) each performed 3 radiation therapy planning cases. The WL levels were subjectively assessed using National Aeronautics and Space Administration Task Load Index (NASA-TLX). Individual performance was assessed objectively based on the severity grade of errors. The relationship between the WL and performance was assessed via ordinal logistic regression. There was an increased rate of severity grade of errors with increasing WL (P value = .02). As the majority of the higher NASA-TLX scores, and the majority of the performance errors were in the residents, our findings are likely most pertinent to radiation oncology centers with training programs. WL levels may be an important factor contributing to errors during radiation therapy planning tasks. Published by Elsevier Inc.

Gastrointestinal Toxicities With Combined Antiangiogenic and Stereotactic Body Radiation Therapy

SciTech Connect

Pollom, Erqi L.; Deng, Lei; Pai, Reetesh K.

2015-07-01

Combining the latest targeted biologic agents with the most advanced radiation technologies has been an exciting development in the treatment of cancer patients. Stereotactic body radiation therapy (SBRT) is an ablative radiation approach that has become established for the treatment of a variety of malignancies, and it has been increasingly used in combination with biologic agents, including those targeting angiogenesis-specific pathways. Multiple reports have emerged describing unanticipated toxicities arising from the combination of SBRT and angiogenesis-targeting agents, particularly of late luminal gastrointestinal toxicities. In this review, we summarize the literature describing these toxicities, explore the biological mechanism of action ofmore » toxicity with the combined use of antiangiogenic therapies, and discuss areas of future research, so that this combination of treatment modalities can continue to be used in broader clinical contexts.« less

High dose bystander effects in spatially fractionated radiation therapy

PubMed Central

Asur, Rajalakshmi; Butterworth, Karl T.; Penagaricano, Jose A.; Prise, Kevin M.; Griffin, Robert J.

2014-01-01

Traditional radiotherapy of bulky tumors has certain limitations. Spatially fractionated radiation therapy (GRID) and intensity modulated radiotherapy (IMRT) are examples of advanced modulated beam therapies that help in significant reductions in normal tissue damage. GRID refers to the delivery of a single high dose of radiation to a large treatment area that is divided into several smaller fields, while IMRT allows improved dose conformity to the tumor target compared to conventional three-dimensional conformal radiotherapy. In this review, we consider spatially fractionated radiotherapy approaches focusing on GRID and IMRT, and present complementary evidence from different studies which support the role of radiation induced signaling effects in the overall radiobiological rationale for these treatments. PMID:24246848

Radiation therapy for breast cancer: Literature review

SciTech Connect

Balaji, Karunakaran, E-mail: karthik.balaji85@gmail.com; School of Advanced Sciences, VIT University, Vellore; Subramanian, Balaji

Concave shape with variable size target volume makes treatment planning for the breast/chest wall a challenge. Conventional techniques used for the breast/chest wall cancer treatment provided better sparing of organs at risk (OARs), with poor conformity and uniformity to the target volume. Advanced technologies such as intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) improve the target coverage at the cost of higher low dose volumes to OARs. Novel hybrid techniques present promising results in breast/chest wall irradiation in terms of target coverage as well as OARs sparing. Several published data compared these technologies for the benefit ofmore » the breast/chest wall with or without nodal volumes. The aim of this article is to review relevant data and identify the scope for further research in developing optimal treatment plan for breast/chest wall cancer treatment.« less

Targeted iron oxide nanoparticles for the enhancement of radiation therapy.

PubMed

Hauser, Anastasia K; Mitov, Mihail I; Daley, Emily F; McGarry, Ronald C; Anderson, Kimberly W; Hilt, J Zach

2016-10-01

To increase the efficacy of radiation, iron oxide nanoparticles can be utilized for their ability to produce reactive oxygen species (ROS). Radiation therapy promotes leakage of electrons from the electron transport chain and leads to an increase in mitochondrial production of the superoxide anion which is converted to hydrogen peroxide by superoxide dismutase. Iron oxide nanoparticles can then catalyze the reaction from hydrogen peroxide to the highly reactive hydroxyl radical. Therefore, the overall aim of this project was to utilize iron oxide nanoparticles conjugated to a cell penetrating peptide, TAT, to escape lysosomal encapsulation after internalization by cancer cells and catalyze hydroxyl radical formation. It was determined that TAT functionalized iron oxide nanoparticles and uncoated iron oxide nanoparticles resulted in permeabilization of the lysosomal membranes. Additionally, mitochondrial integrity was compromised when A549 cells were treated with both TAT-functionalized nanoparticles and radiation. Pre-treatment with TAT-functionalized nanoparticles also significantly increased the ROS generation associated with radiation. A long term viability study showed that TAT-functionalized nanoparticles combined with radiation resulted in a synergistic combination treatment. This is likely due to the TAT-functionalized nanoparticles sensitizing the cells to subsequent radiation therapy, because the nanoparticles alone did not result in significant toxicities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Targeted iron oxide nanoparticles for the enhancement of radiation therapy

PubMed Central

Hauser, Anastasia K.; Mitov, Mihail I.; Daley, Emily F.; McGarry, Ronald C.; Anderson, Kimberly W.; Hilt, J. Zach

2017-01-01

To increase the efficacy of radiation, iron oxide nanoparticles can be utilized for their ability to produce reactive oxygen species (ROS). Radiation therapy promotes leakage of electrons from the electron transport chain and leads to an increase in mitochondrial production of the superoxide anion which is converted to hydrogen peroxide by superoxide dismutase. Iron oxide nanoparticles can then catalyze the reaction from hydrogen peroxide to the highly reactive hydroxyl radical. Therefore, the overall aim of this project was to utilize iron oxide nanoparticles conjugated to a cell penetrating peptide, TAT, to escape lysosomal encapsulation after internalization by cancer cells and catalyze hydroxyl radical formation. It was determined that TAT functionalized iron oxide nanoparticles and uncoated iron oxide nanoparticles resulted in permeabilization of the lysosomal membranes. Additionally, mitochondrial integrity was compromised when A549 cells were treated with both TAT-functionalized nanoparticles and radiation. Pre-treatment with TAT-functionalized nanoparticles also significantly increased the ROS generation associated with radiation. A long term viability study showed that TAT-functionalized nanoparticles combined with radiation resulted in a synergistic combination treatment. This is likely due to the TAT-functionalized nanoparticles sensitizing the cells to subsequent radiation therapy, because the nanoparticles alone did not result in significant toxicities. PMID:27521615

Some computer graphical user interfaces in radiation therapy

PubMed Central

Chow, James C L

2016-01-01

In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls

Some computer graphical user interfaces in radiation therapy.

PubMed

Chow, James C L

2016-03-28

In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls

Modern Radiation Therapy and Cardiac Outcomes in Breast Cancer

SciTech Connect

Boero, Isabel J.; Paravati, Anthony J.; Triplett, Daniel P.

Purpose: Adjuvant radiation therapy, which has proven benefit against breast cancer, has historically been associated with an increased incidence of ischemic heart disease. Modern techniques have reduced this risk, but a detailed evaluation has not recently been conducted. The present study evaluated the effect of current radiation practices on ischemia-related cardiac events and procedures in a population-based study of older women with nonmetastatic breast cancer. Methods and Materials: A total of 29,102 patients diagnosed from 2000 to 2009 were identified from the Surveillance, Epidemiology, and End Results–Medicare database. Medicare claims were used to identify the radiation therapy and cardiac outcomes.more » Competing risk models were used to assess the effect of radiation on these outcomes. Results: Patients with left-sided breast cancer had a small increase in their risk of percutaneous coronary intervention (PCI) after radiation therapy—the 10-year cumulative incidence for these patients was 5.5% (95% confidence interval [CI] 4.9%-6.2%) and 4.5% (95% CI 4.0%-5.0%) for right-sided patients. This risk was limited to women with previous cardiac disease. For patients who underwent PCI, those with left-sided breast cancer had a significantly increased risk of cardiac mortality with a subdistribution hazard ratio of 2.02 (95% CI 1.23-3.34). No other outcome, including cardiac mortality for the entire cohort, showed a significant relationship with tumor laterality. Conclusions: For women with a history of cardiac disease, those with left-sided breast cancer who underwent radiation therapy had increased rates of PCI and a survival decrement if treated with PCI. The results of the present study could help cardiologists and radiation oncologists better stratify patients who need more aggressive cardioprotective techniques.« less

Where Do Patients With Cancer in Iowa Receive Radiation Therapy?

PubMed Central

Ward, Marcia M.; Ullrich, Fred; Matthews, Kevin; Rushton, Gerard; Tracy, Roger; Goldstein, Michael A.; Bajorin, Dean F.; Kosty, Michael P.; Bruinooge, Suanna S.; Hanley, Amy; Jacobson, Geraldine M.; Lynch, Charles F.

2014-01-01

Purpose: Multiple studies have shown survival benefits in patients with cancer treated with radiation therapy, but access to treatment facilities has been found to limit its use. This study was undertaken to examine access issues in Iowa and determine a methodology for conducting a similar national analysis. Patients and Methods: All Iowa residents who received radiation therapy regardless of where they were diagnosed or treated were identified through the Iowa Cancer Registry (ICR). Radiation oncologists were identified through the Iowa Physician Information System (IPIS). Radiation facilities were identified through IPIS and classified using the Commission on Cancer accreditation standard. Results: Between 2004 and 2010, 113,885 invasive cancers in 106,603 patients, 28.5% of whom received radiation treatment, were entered in ICR. Mean and median travel times were 25.8 and 20.1 minutes, respectively, to the nearest facility but 42.4 and 29.1 minutes, respectively, to the patient's chosen treatment facility. Multivariable analysis predicting travel time showed significant relationships for disease site, age, residence location, and facility category. Residents of small and isolated rural towns traveled nearly 3× longer than urban residents to receive radiation therapy, as did patients using certain categories of facilities. Conclusion: Half of Iowa patients could reach their nearest facility in 20 minutes, but instead, they traveled 30 minutes on average to receive treatment. The findings identified certain groups of patients with cancer who chose more distant facilities. However, other groups of patients with cancer, namely those residing in rural areas, had less choice, and some had to travel considerably farther to radiation facilities than urban patients. PMID:24443730

42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

Code of Federal Regulations, 2011 CFR

2011-10-01

... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2. Licenses... radiography, nuclear medicine technology, or radiation therapy technology. 2. Special eligibility to take the...-referenced examination in radiography, nuclear medicine technology, or radiation therapy technology shall be...

42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

Code of Federal Regulations, 2012 CFR

2012-10-01

... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2. Licenses... radiography, nuclear medicine technology, or radiation therapy technology. 2. Special eligibility to take the...-referenced examination in radiography, nuclear medicine technology, or radiation therapy technology shall be...

42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

Code of Federal Regulations, 2013 CFR

2013-10-01

... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2. Licenses... radiography, nuclear medicine technology, or radiation therapy technology. 2. Special eligibility to take the...-referenced examination in radiography, nuclear medicine technology, or radiation therapy technology shall be...

42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

Code of Federal Regulations, 2014 CFR

2014-10-01

... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2. Licenses... radiography, nuclear medicine technology, or radiation therapy technology. 2. Special eligibility to take the...-referenced examination in radiography, nuclear medicine technology, or radiation therapy technology shall be...

Changes in skin microcirculation during radiation therapy for breast cancer.

PubMed

Tesselaar, Erik; Flejmer, Anna M; Farnebo, Simon; Dasu, Alexandru

2017-08-01

The majority of breast cancer patients who receive radiation treatment are affected by acute radiation-induced skin changes. The assessment of these changes is usually done by subjective methods, which complicates the comparison between different treatments or patient groups. This study investigates the feasibility of new robust methods for monitoring skin microcirculation to objectively assess and quantify acute skin reactions during radiation treatment. Laser Doppler flowmetry, laser speckle contrast imaging, and polarized light spectroscopy imaging were used to measure radiation-induced changes in microvascular perfusion and red blood cell concentration (RBC) in the skin of 15 patients undergoing adjuvant radiation therapy for breast cancer. Measurements were made before treatment, once a week during treatment, and directly after the last fraction. In the treated breast, perfusion and RBC concentration were increased after 1-5 fractions (2.66-13.3 Gy) compared to baseline. The largest effects were seen in the areola and the medial area. No changes in perfusion and RBC concentration were seen in the untreated breast. In contrast, Radiation Therapy Oncology Group (RTOG) scores were increased only after 2 weeks of treatment, which demonstrates the potential of the proposed methods for early assessment of skin changes. Also, there was a moderate to good correlation between the perfusion (r = 0.52) and RBC concentration (r = 0.59) and the RTOG score given a week later. We conclude that radiation-induced microvascular changes in the skin can be objectively measured using novel camera-based techniques before visual changes in the skin are apparent. Objective measurement of microvascular changes in the skin may be valuable in the comparison of skin reactions between different radiation treatments and possibly in predicting acute skin effects at an earlier stage.

Advances in radiotherapy techniques and delivery for non-small cell lung cancer: benefits of intensity-modulated radiation therapy, proton therapy, and stereotactic body radiation therapy

PubMed Central

Diwanji, Tejan P.; Mohindra, Pranshu; Vyfhuis, Melissa; Snider, James W.; Kalavagunta, Chaitanya; Mossahebi, Sina; Yu, Jen; Feigenberg, Steven

2017-01-01

The 21st century has seen several paradigm shifts in the treatment of non-small cell lung cancer (NSCLC) in early-stage inoperable disease, definitive locally advanced disease, and the postoperative setting. A key driver in improvement of local disease control has been the significant evolution of radiation therapy techniques in the last three decades, allowing for delivery of definitive radiation doses while limiting exposure of normal tissues. For patients with locally-advanced NSCLC, the advent of volumetric imaging techniques has allowed a shift from 2-dimensional approaches to 3-dimensional conformal radiation therapy (3DCRT). The next generation of 3DCRT, intensity-modulated radiation therapy and volumetric-modulated arc therapy (VMAT), have enabled even more conformal radiation delivery. Clinical evidence has shown that this can improve the quality of life for patients undergoing definitive management of lung cancer. In the early-stage setting, conventional fractionation led to poor outcomes. Evaluation of altered dose fractionation with the previously noted technology advances led to advent of stereotactic body radiation therapy (SBRT). This technique has dramatically improved local control and expanded treatment options for inoperable, early-stage patients. The recent development of proton therapy has opened new avenues for improving conformity and the therapeutic ratio. Evolution of newer proton therapy techniques, such as pencil-beam scanning (PBS), could improve tolerability and possibly allow reexamination of dose escalation. These new progresses, along with significant advances in systemic therapies, have improved survival for lung cancer patients across the spectrum of non-metastatic disease. They have also brought to light new challenges and avenues for further research and improvement. PMID:28529896

Spinal cord protection during radiation therapy

SciTech Connect

Coia, L.; Chu, J.; Larsen, R.

1986-09-01

Treating intrathoracic malignancies to high doses, particularly those of lung and esophagus, requires limiting the radiation dose delivered to the spinal cord. Several factors are important in determining the cord dose. These are: The distance from the block or collimator edge to the cord, the variation of dose with distance from the block or collimator edge and, the expected variation of this distance for clinical set-up from day-to-day. When treating with an oblique beam, the position of the cord may be difficult to identify. A technique for localizing the spinal cord on a simulator film at an arbitrary gantry anglemore » is presented. The technique requires determination of distances from the central axis of the beam to the medial aspect of the pedicle and posterior vertebral body. These can readily be obtained from measurements on orthogonal, AP/PA and lateral isocentric simulator radiographs. A mathematical transformation is applied to determine the corresponding cord locations on the oblique radiographs for any arbitrary gantry angle. The accuracy of cord localization was within 2-3 mm with a precision of 2 mm for five physicians who used this technique. The beam edge characteristics for 60Co, 6 MV, and 10 MV teletherapy unit were measured for various depths and field sizes. For the 6 and 10 MV units, the beam penumbra is nearly independent of the field size, depth and field defining devices (inner and outer collimator jaws, trimmer bars, and shielding blocks). Because the beam penumbra is dependent on the design of the linear accelerator, its measurement should be made individually for each linear accelerator. Our preliminary data on patient positioning uncertainty did not exceed the 6-8 mm limit documented in the literature.« less

Predictive factors for acute radiation pneumonitis in postoperative intensity modulated radiation therapy and volumetric modulated arc therapy of esophageal cancer.

PubMed

Zhao, Yaqin; Chen, Lu; Zhang, Shu; Wu, Qiang; Jiang, Xiaoqin; Zhu, Hong; Wang, Jin; Li, Zhiping; Xu, Yong; Zhang, Ying Jie; Bai, Sen; Xu, Feng

2015-01-01

Radiation pneumonitis (RP) is a common side reaction in radiotherapy for esophageal cancer. There are few reports about RP in esophageal cancer patients receiving postoperative intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). This study aims to analyze clinical or dosimetric factors associated with RP, and provides data for radiotherapy planning. We reviewed 68 postoperative esophageal cancer patients who were treated with radiotherapy at the West China Hospital from October 2010 to November 2012 to identify any correlation between the clinical or dosimetric parameters and acute radiation pneumonitis (ARP) or severe acute radiation pneumonitis (SARP) by t-test, chi-square test, and logistic regression analysis. Of the 68 patients, 33 patients (48.5%) developed ARP, 13 of which (19.1%) developed SARP. Of these 33 patients, 8 (11.8%), 12 (17.6%), 11 (16.2%), and 2 (2.9%) patients were grade 1, 2, 3, and 4 ARP, respectively. Univariate analysis showed that lung infection during radiotherapy, use of VMAT, mean lung dose (MLD), and dosimetric parameters (e.g. V20, V30) are significantly correlated with RP. Multivariate analysis found that lung infection during radiotherapy, MLD ≥ 12 Gy, and V30 ≥ 13% are significantly correlated with an increased risk of RP. Lung infection during radiotherapy and low radiation dose volume distribution were predictive factors associated with RP and should be accounted for during radiation planning.

Gold nanoparticles and their alternatives for radiation therapy enhancement

PubMed Central

Cooper, Daniel R.; Bekah, Devesh; Nadeau, Jay L.

2014-01-01

Radiation therapy is one of the most commonly used treatments for cancer. The dose of delivered ionizing radiation can be amplified by the presence of high-Z materials via an enhancement of the photoelectric effect; the most widely studied material is gold (atomic number 79). However, a large amount is needed to obtain a significant dose enhancement, presenting a challenge for delivery. In order to make this technique of broader applicability, the gold must be targeted, or alternative formulations developed that do not rely solely on the photoelectric effect. One possible approach is to excite scintillating nanoparticles with ionizing radiation, and then exploit energy transfer between these particles and attached dyes in a manner analogous to photodynamic therapy (PDT). Doped rare-earth halides and semiconductor quantum dots have been investigated for this purpose. However, although the spectrum of emitted light after radiation excitation is usually similar to that seen with light excitation, the yield is not. Measurement of scintillation yields is challenging, and in many cases has been done only for bulk materials, with little understanding of how the principles translate to the nanoscale. Another alternative is to use local heating using gold or iron, followed by application of ionizing radiation. Hyperthermia pre-sensitizes the tumors, leading to an improved response. Another approach is to use chemotherapeutic drugs that can radiosensitize tumors. Drugs may be attached to high-Z nanoparticles or encapsulated. This article discusses each of these techniques, giving an overview of the current state of nanoparticle-assisted radiation therapy and future directions. PMID:25353018

21 CFR 892.5710 - Radiation therapy beam-shaping block.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Radiation therapy beam-shaping block. 892.5710... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy beam-shaping block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...

21 CFR 892.5710 - Radiation therapy beam-shaping block.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Radiation therapy beam-shaping block. 892.5710... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy beam-shaping block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...

21 CFR 892.5710 - Radiation therapy beam-shaping block.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Radiation therapy beam-shaping block. 892.5710... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy beam-shaping block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...

21 CFR 892.5050 - Medical charged-particle radiation therapy system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical charged-particle radiation therapy system...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons...

21 CFR 892.5050 - Medical charged-particle radiation therapy system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical charged-particle radiation therapy system...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons...

21 CFR 892.5050 - Medical charged-particle radiation therapy system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical charged-particle radiation therapy system...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons...

21 CFR 892.5710 - Radiation therapy beam-shaping block.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Radiation therapy beam-shaping block. 892.5710... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy beam-shaping block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...

An update on radiation therapy in head and neck cancers.

PubMed

Mazzola, Rosario; Fiorentino, Alba; Ricchetti, Francesco; Gregucci, Fabiana; Corradini, Stefanie; Alongi, Filippo

2018-04-01

Technological and technical improvements allowed for significant advances in the field of radiation therapy (RT) of head and neck cancer (HNC). Several organ-sparing strategies have been investigated with the objective to decrease acute and long-term adverse effects and, subsequently, to assure a better quality of life in patients affected by HNC. In this context, intensity modulated irradiation and the use of multimodality-imaging could help clinicians to obtain a rapid dose fall off towards surrounding healthy tissues and a better delineation of targets volumes and organs at risk. Areas covered: A literature review was performed with the aim to offer an update on radiation therapy in HNC. Expert commentary: During these last years, radiation oncologists have observed a continuous changing regarding radiation treatment for HNC. The adoption of intensity-modulated RT (IMRT) and the use of multimodality-imaging for tumor volume definition and organs at risk or delineation have improved the clinical outcomes of HNC patients. In the future, a better integration of functional imaging for target volume delineation as well as adaptive delivery strategies will allow to further personalize radiation oncology in HNC. Furthermore, the latest breakthrough technologies, such as magnetic resonance imaging (MRI)-linacs and heavy particles technologies have a great potential to improve treatment-related quality of life in HNC. Future studies are needed to demonstrate the clinical advantages of these new RT technologies in HNC.

Shielding and Radiation Protection in Ion Beam Therapy Facilities

NASA Astrophysics Data System (ADS)

Wroe, Andrew J.; Rightnar, Steven

Radiation protection is a key aspect of any radiotherapy (RT) department and is made even more complex in ion beam therapy (IBT) by the large facility size, secondary particle spectra and intricate installation of these centers. In IBT, large and complex radiation producing devices are used and made available to the public for treatment. It is thus the responsibility of the facility to put in place measures to protect not only the patient but also the general public, occupationally and nonoccupationally exposed personnel working within the facility, and electronics installed within the department to ensure maximum safety while delivering maximum up-time.

A biomaterial-assisted mesenchymal stromal cell therapy alleviates colonic radiation-induced damage.

PubMed

Moussa, Lara; Pattappa, Girish; Doix, Bastien; Benselama, Sarra-Louiza; Demarquay, Christelle; Benderitter, Marc; Sémont, Alexandra; Tamarat, Radia; Guicheux, Jérôme; Weiss, Pierre; Réthoré, Gildas; Mathieu, Noëlle

2017-01-01

Healthy tissues surrounding abdomino-pelvic tumours can be impaired by radiotherapy, leading to chronic gastrointestinal complications with substantial mortality. Adipose-derived Mesenchymal Stromal Cells (Ad-MSCs) represent a promising strategy to reduce intestinal lesions. However, systemic administration of Ad-MSCs results in low cell engraftment within the injured tissue. Biomaterials, able to encapsulate and withstand Ad-MSCs, can overcome these limitations. A silanized hydroxypropylmethyl cellulose (Si-HPMC) hydrogel has been designed and characterized for injectable cell delivery using the operative catheter of a colonoscope. We demonstrated that hydrogel loaded-Ad-MSCs were viable, able to secrete trophic factors and responsive to the inflammatory environment. In a rat model of radiation-induced severe colonic damage, Ad-MSC + Si-HPMC improve colonic epithelial structure and hyperpermeability compared with Ad-MSCs injected intravenously or locally. This therapeutic benefit is associated with greater engraftment of Si-HPMC-embedded Ad-MSCs in the irradiated colonic mucosa. Moreover, macrophage infiltration near the injection site was less pronounced when Ad-MSCs were embedded in the hydrogel. Si-HPMC induces modulation of chemoattractant secretion by Ad-MSCs that could contribute to the decrease in macrophage infiltrate. Si-HPMC is suitable for cell delivery by colonoscopy and induces protection of Ad-MSCs in the tissue potentiating their therapeutic effect and could be proposed to patients suffering from colon diseases. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Radiation pneumonitis in breast cancer patients treated with conservative surgery and radiation therapy

SciTech Connect

Lingos, T.I.; Recht, A.; Vicini, F.

1991-07-01

The likelihood of radiation pneumonitis and factors associated with its development in breast cancer patients treated with conservative surgery and radiation therapy have not been well established. To assess these, the authors retrospectively reviewed 1624 patients treated between 1968 and 1985. Median follow-up for patients without local or distant failure was 77 months. Patients were treated with either tangential fields alone (n = 508) or tangents with a third field to the supraclavicular (SC) or SC-axillary (AX) region (n = 1116). Lung volume treated in the tangential fields was generally limited by keeping the perpendicular distance (demagnified) at the isocentermore » from the deep field edges to the posterior chest wall (CLD) to 3 cm or less. Seventeen patients with radiation pneumonitis were identified (1.0%). Radiation pneumonitis was diagnosed when patients presented with cough (15/17, 88%), fever (9/17, 53%), and/or dyspnea (6/17, 35%) and radiographic changes (17/17) following completion of RT. Radiographic infiltrates corresponded to treatment portals in all patients, and in 12 of the 17 patients, returned to baseline within 1-12 months. Five patients had permanent scarring on chest X ray. No patient had late or persistent pulmonary symptoms. The incidence of radiation pneumonitis was correlated with the combined use of chemotherapy (CT) and a third field. Three percent (11/328) of patients treated with a 3-field technique who received chemotherapy developed radiation pneumonitis compared to 0.5% (6 of 1296) for all other patients (p = 0.0001). When patients treated with a 3-field technique received chemotherapy concurrently with radiation therapy, the incidence of radiation pneumonitis was 8.8% (8/92) compared with 1.3% (3/236) for those who received sequential chemotherapy and radiation therapy (p = 0.002).« less

Ion chambers compliance results of Brazilian radiation therapy facilities.

PubMed

Joana, G; Salata, C; Leal, P; Vasconcelos, R; Couto, N do; Teixeira, F C; Soares, A D; Santini, E S; Gonçalves, M

2018-03-01

The Brazilian Nuclear Energy Commission (cnen) has been making a constant effort to keep up to date with international standards and national needs to strengthen the status of radiological protection of the country. The guidelines related to radiation therapy facilities have been revised in the last five years in order to take into consideration the most relevant aspects of the growing technology as well as to mitigate the accidents or incidents observed in practice. Hence, clinical dosimeters have gained special importance in this matter. In the present work, we discuss the effectiveness of regulation and inspections to the enforcement of instrument calibration accuracy for the improvement of patient dosimetry and quality control. As a result, we observed that the number of calibrated instruments, mainly well chambers, is increasing each year. The same behavior is observed for instruments employed in technologically advanced radiation treatments such as intensity modulated radiotherapy, volumetric therapy and stereotatic radiosurgery. We ascribe this behavior to the new regulation.

[Efficacy of Radiation Therapy for Esophageal Cancer with Bone Metastases].

PubMed

Katayanagi, So; Watanabe, Takafumi; Makuuchi, Yosuke; Shigoka, Masatoshi; Sumi, Tetsuo; Takagaki, Shinichi; Okubo, Mitsuru; Tachibana, Shingo; Oosaka, Yoshiaki; Tsuchida, Akihiko; Kawachi, Shigeyuki

2015-11-01

We retrospectively considered the validity of radiotherapy for patients with bone metastases from esophageal cancer. Eight patients have received radiotherapy in our hospital since 2007. The median age of the patients was 63 years, with 5 men and 3 women. Bone metastatic sites were 4 to the vertebrae, 3 to the ribs, 3 to the femur and 1 each to the humerus, ulna, and radius, respectively. All of the patients had other unresectable sites of metastasis. Radiotherapy reduced pain of 3 patients of PS 1 clearly. Median survival time from the start of radiation therapy was 50 days. When PS was relatively good, the possibility of easing pain and improving QOL was suggested by our data. There is a possibility that radiation therapy for patients with bone metastases from esophageal cancer can improve the QOL and alleviate pain.

Adaptive radiation therapy of prostate cancer

NASA Astrophysics Data System (ADS)

Wen, Ning

standard deviation of markers after rigid registration in L-R direction was 0 and 1 mm. But the mean was 2--4 mm in the A-P and S-I direction and standard deviation was about 2 mm. After DIR, the mean in all three directions became 0 and standard deviation was within sub millimeter. UE images were generated for each CT set and carefully reviewed in the prostate region. DIR provided accurate transformation matrix to be used for dose reconstruction. The delivered dose was evaluated with radiobiological models. TCP for the CTV was calculated to evaluate tumor control in different margin settings. TCP calculated from the reconstructed dose agreed within 5% of the value in the plan for all patients with three different margins. EUD and NTCP were calculated to evaluate reaction of rectum to radiation. Similar biological evaluation was performed for bladder. EUD of actual dose was 3%--9% higher than that of planned dose of patient 1--3, 11%--20% higher of patient 4--5. Smaller margins could not reduce late GU toxicity effectively since bladder complication was directly related to Dmax which was at the same magnitude in the bladder no matter which margin was applied. Re-optimization was performed at the 10th, 20th , 30th, and 40th fraction to evaluate the effectiveness to limit OAR dose while maintaining the target coverage. Reconstructed dose was added to dose from remaining fractions after optimization to show the total dose patient would receive. It showed that if the plan was re-optimized at 10th or 20th fraction, total dose to rectum and bladder were very similar to planned dose with minor deviations. If the plan was re-optimized at the 30th fraction, since there was a large deviation between reconstructed dose and planned dose to OAR, optimization could not limit the OAR dose to the original plan with only 12 fractions left. If the re-optimization was done at the 40th fraction, it was impossible to compensate in the last 2 fractions. Large deviations of total dose to bladder

Abdominopelvic 1.5-T and 3.0-T MR Imaging in Healthy Volunteers: Relationship to Formation of DNA Double-Strand Breaks.

PubMed

Suntharalingam, Saravanabavaan; Mladenov, Emil; Sarabhai, Theresia; Wetter, Axel; Kraff, Oliver; Quick, Harald H; Forsting, Michael; Iliakis, Georg; Nassenstein, Kai

2018-05-01

Purpose To investigate the relationship between abdominopelvic magnetic resonance (MR) imaging and formation of DNA double-strand breaks (DSBs) in peripheral blood lymphocytes among a cohort of healthy volunteers. Materials and Methods Blood samples were obtained from 40 healthy volunteers (23 women and 17 men; mean age, 27.2 years [range, 21-37 years]) directly before and 5 and 30 minutes after abdominopelvic MR imaging performed at 1.5 T (n = 20) or 3.0 T (n = 20). The number of DNA DSBs in isolated blood lymphocytes was quantified after indirect immunofluorescent staining of a generally accepted DSB marker, γ-H2AX, by means of high-throughput automated microscopy. As a positive control of DSB induction, blood lymphocytes from six volunteers were irradiated in vitro with x-rays at a dose of 1 Gy (70-90 keV). Statistical analysis was performed by using a Friedman test. Results No significant alteration in the frequency of DNA DSB induction was observed after MR imaging (before imaging: 0.22 foci per cell, interquartile range [IQR] = 0.54 foci per cell; 5 minutes after MR imaging: 0.08 foci per cell, IQR = 0.39 foci per cell; 30 minutes after MR imaging: 0.09 foci per cell, IQR = 0.63 foci per cell; P = .057). In vitro radiation of lymphocytes with 1 Gy led to a significant increase in DSBs (0.22 vs 3.43 foci per cell; P = .0312). The frequency of DSBs did not differ between imaging at 1.5 T and at 3.0 T (5 minutes after MR imaging: 0.23 vs 0.06 foci per cell, respectively [P = .57]; 30 minutes after MR imaging: 0.12 vs 0.08 foci per cell [P = .76]). Conclusion Abdominopelvic MR imaging performed at 1.5 T or 3.0 T does not affect the formation of DNA DSBs in peripheral blood lymphocytes. © RSNA, 2018.

Occupational therapy intervention with radiation-induced brachial plexopathy.

PubMed

Cooper, J

1998-06-01

Occupational therapy intervention minimizes disability and facilitates optimum functional independence. The range of dysfunction experienced by patients with radiation-induced brachial plexopathy includes physical, psychological, emotional and social difficulties. The occupational therapist works as part of the multiprofessional team to use a client-centred, problem-solving approach to address the problems and enable the patient to adapt to the altered body image and disabilities.

Massive osteolysis of the right clavicle developing after radiation therapy

SciTech Connect

Skinner, W.L.; Buzdar, A.U.; Libshitz, H.I.

1988-07-15

This report describes an unusual case of clavicular osteolysis, a late complication of radiation therapy for breast cancer, and demonstrates the diagnostic implications that radiotherapy changes can pose. Radiotherapy to the chest wall produces a spectrum of alterations in bone over time, ranging from early roentgenographic findings of osteoporosis and trabecular thickening to spontaneous fractures and changes that may be confused with metastatic disease or postirradiation sarcoma.

Lymph Node Metastases Optical Molecular Diagnostic and Radiation Therapy

DTIC Science & Technology

2017-03-01

structures and not molecular functions. The one tool commonly used for metastases imaging is nuclear medicine. Positron emission tomography, PET, is...be visualized at a relevant stage., largely because most imaging is based upon structures and not molecular functions. But there are no tools to...system suitable for imaging signals from in small animals on the standard radiation therapy tools. (3) To evaluate the limits on structural , metabolic

Sick sinus syndrome as a complication of mediastinal radiation therapy

SciTech Connect

Pohjola-Sintonen, S.; Toetterman, K.J.K.; Kupari, M.

1990-06-01

A 33-year-old man who had received mediastinal radiation therapy for Hodgkin's disease 12 years earlier developed a symptomatic sick sinus syndrome requiring the implantation of a permanent pacemaker. The sick sinus syndrome and a finding of an occult constrictive pericarditis were considered to be due to the previous mediastinal irradiation. A ventricular pacemaker was chosen because mediastinal radiotherapy also increases the risk of developing atrioventricular conduction defects.

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT).

PubMed

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

2013-12-01

Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147-53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose-volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

PubMed Central

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

2013-01-01

Introduction Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. Methods A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. Results The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. Conclusion The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques. PMID:26229623

NEW DEVELOPMENTS IN RADIATION THERAPY FOR HEAD AND NECK CANCER: INTENSITY MODULATED RADIATION THERAPY AND HYPOXIA TARGETING

PubMed Central

Lee, Nancy Y.; Le, Quynh-Thu

2008-01-01

Intensity modulated radiation therapy (IMRT) has revolutionized radiation treatment for head and neck cancers (HNC). When compared to the traditional techniques, IMRT has the unique ability to minimize the dose delivered to normal tissues without compromising tumor coverage. As a result, side effects from high dose radiation have decreased and patient quality of life has improved. In addition to toxicity reduction, excellent clinical outcomes have been reported for IMRT. The first part of this review will focus on clinical results of IMRT for HNC. Tumor hypoxia or the condition of low oxygen is a key factor for tumor progression and treatment resistance. Hypoxia develops in solid tumors due to aberrant blood vessel formation, fluctuation in blood flow and increasing oxygen demands for tumor growth. Because hypoxic tumor cells are more resistant to ionizing radiation, hypoxia has been a focus of clinical research in radiation therapy for half a decade. Interest for targeting tumor hypoxia have waxed and waned as promising treatments emerged from the laboratory, only to fail in the clinics. However, with the development of new technologies, the prospect of targeting tumor hypoxia is more tangible. The second half of the review will focus on approaches for assessing tumor hypoxia and on the strategies for targeting this important microenvironmental factor in HNC. PMID:18544439

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

SciTech Connect

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRTmore » plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.« less

Ultrasound Imaging in Radiation Therapy: From Interfractional to Intrafractional Guidance

PubMed Central

Western, Craig; Hristov, Dimitre

2015-01-01

External beam radiation therapy (EBRT) is included in the treatment regimen of the majority of cancer patients. With the proliferation of hypofractionated radiotherapy treatment regimens, such as stereotactic body radiation therapy (SBRT), interfractional and intrafractional imaging technologies are becoming increasingly critical to ensure safe and effective treatment delivery. Ultrasound (US)-based image guidance systems offer real-time, markerless, volumetric imaging with excellent soft tissue contrast, overcoming the limitations of traditional X-ray or computed tomography (CT)-based guidance for abdominal and pelvic cancer sites, such as the liver and prostate. Interfractional US guidance systems have been commercially adopted for patient positioning but suffer from systematic positioning errors induced by probe pressure. More recently, several research groups have introduced concepts for intrafractional US guidance systems leveraging robotic probe placement technology and real-time soft tissue tracking software. This paper reviews various commercial and research-level US guidance systems used in radiation therapy, with an emphasis on hardware and software technologies that enable the deployment of US imaging within the radiotherapy environment and workflow. Previously unpublished material on tissue tracking systems and robotic probe manipulators under development by our group is also included. PMID:26180704

Radiation therapy oncology group gynecologic oncology working group: comprehensive results.

PubMed

Gaffney, David K; Jhingran, Anuja; Portelance, Lorraine; Viswanathan, Akila; Schefter, Tracey; Weidhaas, Joanne; Small, William

2014-06-01

The purpose of this report was to comprehensively describe the activities of the Gynecologic Oncology Working Group within the Radiation Therapy Oncology Group (RTOG). Clinical trials will be reviewed as well as translational science and ancillary activities. During the past 40 years, a myriad of clinical trials have been performed within the RTOG with the aim of improving overall survival (OS) and decreasing morbidity in women with cervical or endometrial cancer. Major study questions have included hyperbaric oxygen, neutron radiotherapy, altered fractionation, hypoxic cell sensitization, chemosensitization, and volume-directed radiotherapy.RTOG 7920 demonstrated improvement in OS in patients with stages IB through IIB cervical carcinoma receiving prophylactic para-aortic irradiation compared to pelvic radiation alone. RTOG 9001 demonstrated that cisplatin and 5-FU chemoradiotherapy to the pelvis for advanced cervix cancer markedly improved OS compared to extended field radiotherapy alone. More recent trials have used radioprotectors, molecular-targeted therapy, and intensity-modulated radiation therapy. Ancillary studies have developed clinical target volume atlases for research protocols and routine clinical use. Worldwide practice patterns have been investigated in cervix, endometrial, and vulvar cancer through the Gynecologic Cancer Intergroup. Translational studies have focused on immunohistochemical markers, changes in gene expression, and miRNA patterns impacting prognosis.The RTOG gynecologic working group has performed clinical trials that have defined the standard of care, improved survival, and added to our understanding of the biology of cervical and endometrial cancers.

Predictors of Urgent Findings on Abdominopelvic CT in Patients with Crohn's Disease Presenting to the Emergency Department.

PubMed

Jung, Yoon Suk; Park, Dong Il; Hong, Sung Noh; Kim, Eun Ran; Kim, Young Ho; Cheon, Jae Hee; Eun, Chang Soo; Han, Dong Soo; Lee, Chang Kyun; Kim, Jae Hak; Huh, Kyu Chan; Yoon, Soon Man; Song, Hyun Joo; Shin, Jeong Eun; Jeon, Seong Ran

2015-04-01

Patients with Crohn's disease (CD) are frequently exposed to diagnostic radiation, mainly as a result of abdominopelvic computed tomography (APCT) examinations. However, there are limited data on the impact of APCT on clinical management in this population. To investigate clinical predictors of urgent findings on APCT in patients with CD who presented to the emergency department (ED). A retrospective study was performed among patients with CD presenting to 11 EDs with a gastrointestinal complaint. The primary outcome, OPAN (obstruction, perforation, abscess, or non-CD-related urgent findings), included new or worsening CD-related urgent findings or non-CD-related urgent findings that required urgent or emergency treatment. Variables with P < 0.1 in univariate analyses were included in a multivariable logistic regression model. Of the 266 APCTs performed, 103 (38.7 %) had OPAN and 113 (42.5 %) required changes in treatment plan. Stricturing or penetrating disease (odds ratio [OR] 2.72, 95 % confidence interval [CI] 1.21-6.13), heart rate >100 beats/min (OR 2.33, 95 % CI 1.10-4.93), leukocyte count >10,000/mm(3) (OR 4.38, 95 % CI 2.10-9.13), and CRP >2.5 mg/dL (OR 3.11, 95 % CI 1.23-7.86) were identified as the independent predictors of OPAN, whereas biologic agent use (OR 0.37; 95 % CI 0.15-0.90) was identified as the negative predictor in patients with CD. Only 39 % of the APCTs performed in the ED among patients with CD showed urgent findings. Stricturing or penetrating disease, tachycardia, leukocytosis, and high CRP level were predictors of urgent CT findings, while biologic agent use was a negative predictor. To reduce unnecessary radiation exposure, the selection process for CD patients referred for APCT must be improved.

Safety of minimally invasive radical prostatectomy in patients with prior abdominopelvic or inguinal surgery.

PubMed

Ball, Mark W; Reese, Adam C; Mettee, Lynda Z; Pavlovich, Christian P

2015-02-01

Despite the widespread use of minimally invasive radical prostatectomy (MIRP), there remain concerns regarding its safety in patients with a history of prior abdominopelvic or inguinal surgery. A prospective database of 1165 MIRP procedures performed by a single surgeon at a high-volume tertiary care center from 2001 to 2013 was analyzed. After an initial period of transperitoneal MIRP (TP), an extraperitoneal (EP) approach was used preferentially beginning in 2005 (for both laparoscopic and robotic cases), and robotics were used preferentially beginning in 2010. Overall perioperative complications, major complications (Clavien-Dindo III or IV), and abdominal complications (e.g., ileus, bowel/organ injury, or vascular injury) were compared for patients with and without a prior surgical history. Uni- and multivariate logistic regression were used to control the impact of robotics, approach, operative time, estimated blood loss, case number, prostate weight, and primary Gleason on complications. Three hundred patients undergoing MIRP had prior abdominopelvic or inguinal surgery (25.8%). Of these, 102 (34%) underwent TP and 198 (66%) EP MIRP. Robotics was used in 286 cases (24.6%) and pure laparoscopy in 879 (75.4%). Complications occurred in 111 patients (9.5%) from the total cohort, with major complications in 32 (2.75%) and abdominal complications in 19 (1.63%). Prior surgery was not associated with overall, major, or abdominal complications. Of the controlling factors, only increasing operative time was associated with postoperative abdominal complications (most of which were ileus) on multivariate analysis. In this large single-surgeon series where both EP and TP approaches to MIRP are utilized, prior abdominopelvic or inguinal surgery was not associated with an increased risk of perioperative complications.

Brachytherapy with an improved MammoSite Radiation Therapy System

NASA Astrophysics Data System (ADS)

Karthik, Nanda; Keppel, Cynthia; Nazaryan, Vahagn

2007-03-01

Accelerated partial breast irradiation treatment utilizing the MammoSite Radiation Therapy System (MRTS) is becoming increasingly popular. Clinical studies show excellent results for disease control and localization, as well as for cosmesis. Several Phase I, II, and III clinical trials have found significant association between skin spacing and cosmetic results after treatment with MRTS. As a result, patients with skin spacing less then 7 mm are not recommended to undergo this treatment. We have developed a practical innovation to the MammoSite brachytherapy methodology that is directed to overcome the skin spacing problem. The idea is to partially shield the radiation dose to the skin where the skin spacing is less then 7 mm, thereby protecting the skin from radiation damage. Our innovation to the MRTS will allow better cosmetic outcome in breast conserving therapy (BCT), and will furthermore allow more women to take advantage of BCT. Reduction in skin radiation exposure is particularly important for patients also undergoing adjuvant chemotherapy. We will present the method and preliminary laboratory and Monte Carlo simulation results.

Definitive radiation therapy for squamous cell carcinoma of the vagina

SciTech Connect

Frank, Steven J.; Jhingran, Anuja; Levenback, Charles

2005-05-01

Purpose: To evaluate outcome and describe clinical treatment guidelines for patients with primary squamous cell carcinoma of the vagina treated with definitive radiation therapy. Methods and Materials: Between 1970 and 2000, a total of 193 patients were treated with definitive radiation therapy for squamous cell carcinoma of the vagina at The University of Texas M. D. Anderson Cancer Center. The patients' medical records were reviewed to obtain information about patient, tumor, and treatment characteristics, as well as outcome and patterns of recurrence. Surviving patients were followed for a median of 137 months. Survival rates were calculated using the Kaplan-Meier method,more » with differences assessed using log-rank tests. Results: Disease-specific survival (DSS) and pelvic disease control rates correlated with International Federation of Gynecology and Obstetrics (FIGO) stage and tumor size. At 5 years, DSS rates were 85% for the 50 patients with Stage I, 78% for the 97 patients with Stage II, and 58% for the 46 patients with Stage III-IVA disease (p = 0.0013). Five-year DSS rates were 82% and 60% for patients with tumors {<=}4 cm or >4 cm, respectively (p = 0.0001). At 5 years, pelvic disease control rates were 86% for Stage I, 84% for Stage II, and 71% for Stage III-IVA (p = 0.027). The predominant mode of relapse after definitive radiation therapy was local-regional (68% and 83%, respectively, for patients with stages I-II or III-IVA disease). The incidence of major complications was correlated with FIGO stage; at 5 years, the rates of major complications were 4% for Stage I, 9% for Stage II, and 21% for Stage III-IVA (p < 0.01). Conclusions: Excellent outcomes can be achieved with definitive radiation therapy for invasive squamous cell carcinoma of the vagina. However, to achieve these results, treatment must be individualized according to the site and size of the tumor at presentation and the response to initial external-beam radiation therapy

Successful pregnancy after radiation therapy for carcinoma of the cervix

SciTech Connect

Whelton, James A.; McSweeney, Daniel J.

Radiosensitivity of the ovary is considered, and the possibility of recovery of ovarian function following pelvic radiotherapy is evaluated with reference to previously reported cases and a new case. In the standard radiation program of combined Ra and x-ray therapy currently employed for the control of carcinoma of the cervix, thc amount of radiation delivered to the gonads makes preservation of ovarian function nearly impossible. Even after Ra therapy alone for cervical cancer, continued ovarian activity as evidenced by regular menstruation is infrequent, and successful pregnancy after Ra treatment for a malignant growth on the cervix is an extremely raremore » occurrence. Data are tabulated for nine previous cases in which pregnancy occurred after radiotherapy for cervical carcinoma. In the present case, a 21-yr-old women was treated with 5000 mg-hr and became pregnant twice, four and six yrs later. No external x-ray therapy was given. The patient experienced vaginal bleeding consistent with a menstrual period in each of the first two months after Ra insertion but had total amenorrhea for the next year. Rectal bleeding and diarrhea six months later because of radiation proctitis. A cervical biopsy performed three yr later showed a severe radiation reaction. Regular menses commenced four months after this procedure. Both pregnancies terminated prematurely but in both instances an apparently normal infant was born, and no subsequent abnormalities in their growth, development, or behaviour were noted. In the reviewed group of cases, preservation of ovarian function was attributed in great measure to the increased distance of the ovaries from the Ra source because of an intrauterine gestation (five cases), recent parturition (one case), recent miscarriage (one case), and a large exophytic tumor (one case). The existence of an amenorrheic state for nine months in one earlier case and for 12 months in the present case indicates that the radiosensitive gonads were

TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists

SciTech Connect

Orton, C; Borras, C; Carlson, D

Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protectionmore » will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples

Survival times for canine intranasal sarcomas treated with radiation therapy: 86 cases (1996-2011).

PubMed

Sones, Evan; Smith, Annette; Schleis, Stephanie; Brawner, William; Almond, Gregory; Taylor, Kathryn; Haney, Siobhan; Wypij, Jackie; Keyerleber, Michele; Arthur, Jennifer; Hamilton, Terrance; Lawrence, Jessica; Gieger, Tracy; Sellon, Rance; Wright, Zack

2013-01-01

Sarcomas comprise approximately one-third of canine intranasal tumors, however few veterinary studies have described survival times of dogs with histologic subtypes of sarcomas separately from other intranasal tumors. One objective of this study was to describe median survival times for dogs treated with radiation therapy for intranasal sarcomas. A second objective was to compare survival times for dogs treated with three radiation therapy protocols: daily-fractionated radiation therapy; Monday, Wednesday, and Friday fractionated radiation therapy; and palliative radiation therapy. Medical records were retrospectively reviewed for dogs that had been treated with radiation therapy for confirmed intranasal sarcoma. A total of 86 dogs met inclusion criteria. Overall median survival time for included dogs was 444 days. Median survival time for dogs with chondrosarcoma (n = 42) was 463 days, fibrosarcoma (n = 12) 379 days, osteosarcoma (n = 6) 624 days, and undifferentiated sarcoma (n = 22) 344 days. Dogs treated with daily-fractionated radiation therapy protocols; Monday, Wednesday and Friday fractionated radiation therapy protocols; and palliative radiation therapy protocols had median survival times of 641, 347, and 305 days, respectively. A significant difference in survival time was found for dogs receiving curative intent radiation therapy vs. palliative radiation therapy (P = 0.032). A significant difference in survival time was also found for dogs receiving daily-fractionated radiation therapy vs. Monday, Wednesday and Friday fractionated radiation therapy (P = 0.0134). Findings from this study support the use of curative intent radiation therapy for dogs with intranasal sarcoma. Future prospective, randomized trials are needed for confirmation of treatment benefits. © 2012 Veterinary Radiology & Ultrasound.

Anonymization of DICOM Electronic Medical Records for Radiation Therapy

PubMed Central

Newhauser, Wayne; Jones, Timothy; Swerdloff, Stuart; Newhauser, Warren; Cilia, Mark; Carver, Robert; Halloran, Andy; Zhang, Rui

2014-01-01

Electronic medical records (EMR) and treatment plans are used in research on patient outcomes and radiation effects. In many situations researchers must remove protected health information (PHI) from EMRs. The literature contains several studies describing the anonymization of generic Digital Imaging and Communication in Medicine (DICOM) files and DICOM image sets but no publications were found that discuss the anonymization of DICOM radiation therapy plans, a key component of an EMR in a cancer clinic. In addition to this we were unable to find a commercial software tool that met the minimum requirements for anonymization and preservation of data integrity for radiation therapy research. The purpose of this study was to develop a prototype software code to meet the requirements for the anonymization of radiation therapy treatment plans and to develop a way to validate that code and demonstrate that it properly anonymized treatment plans and preserved data integrity. We extended an open-source code to process all relevant PHI and to allow for the automatic anonymization of multiple EMRs. The prototype code successfully anonymized multiple treatment plans in less than 1 minute per patient. We also tested commercial optical character recognition (OCR) algorithms for the detection of burned-in text on the images, but they were unable to reliably recognize text. In addition, we developed and tested an image filtering algorithm that allowed us to isolate and redact alpha-numeric text from a test radiograph. Validation tests verified that PHI was anonymized and data integrity, such as the relationship between DICOM unique identifiers (UID) was preserved. PMID:25147130

Anonymization of DICOM electronic medical records for radiation therapy.

PubMed

Newhauser, Wayne; Jones, Timothy; Swerdloff, Stuart; Newhauser, Warren; Cilia, Mark; Carver, Robert; Halloran, Andy; Zhang, Rui

2014-10-01

Electronic medical records (EMR) and treatment plans are used in research on patient outcomes and radiation effects. In many situations researchers must remove protected health information (PHI) from EMRs. The literature contains several studies describing the anonymization of generic Digital Imaging and Communication in Medicine (DICOM) files and DICOM image sets but no publications were found that discuss the anonymization of DICOM radiation therapy plans, a key component of an EMR in a cancer clinic. In addition to this we were unable to find a commercial software tool that met the minimum requirements for anonymization and preservation of data integrity for radiation therapy research. The purpose of this study was to develop a prototype software code to meet the requirements for the anonymization of radiation therapy treatment plans and to develop a way to validate that code and demonstrate that it properly anonymized treatment plans and preserved data integrity. We extended an open-source code to process all relevant PHI and to allow for the automatic anonymization of multiple EMRs. The prototype code successfully anonymized multiple treatment plans in less than 1min/patient. We also tested commercial optical character recognition (OCR) algorithms for the detection of burned-in text on the images, but they were unable to reliably recognize text. In addition, we developed and tested an image filtering algorithm that allowed us to isolate and redact alpha-numeric text from a test radiograph. Validation tests verified that PHI was anonymized and data integrity, such as the relationship between DICOM unique identifiers (UID) was preserved. Copyright © 2014 Elsevier Ltd. All rights reserved.

A point kernel algorithm for microbeam radiation therapy

NASA Astrophysics Data System (ADS)

Debus, Charlotte; Oelfke, Uwe; Bartzsch, Stefan

2017-11-01

Microbeam radiation therapy (MRT) is a treatment approach in radiation therapy where the treatment field is spatially fractionated into arrays of a few tens of micrometre wide planar beams of unusually high peak doses separated by low dose regions of several hundred micrometre width. In preclinical studies, this treatment approach has proven to spare normal tissue more effectively than conventional radiation therapy, while being equally efficient in tumour control. So far dose calculations in MRT, a prerequisite for future clinical applications are based on Monte Carlo simulations. However, they are computationally expensive, since scoring volumes have to be small. In this article a kernel based dose calculation algorithm is presented that splits the calculation into photon and electron mediated energy transport, and performs the calculation of peak and valley doses in typical MRT treatment fields within a few minutes. Kernels are analytically calculated depending on the energy spectrum and material composition. In various homogeneous materials peak, valley doses and microbeam profiles are calculated and compared to Monte Carlo simulations. For a microbeam exposure of an anthropomorphic head phantom calculated dose values are compared to measurements and Monte Carlo calculations. Except for regions close to material interfaces calculated peak dose values match Monte Carlo results within 4% and valley dose values within 8% deviation. No significant differences are observed between profiles calculated by the kernel algorithm and Monte Carlo simulations. Measurements in the head phantom agree within 4% in the peak and within 10% in the valley region. The presented algorithm is attached to the treatment planning platform VIRTUOS. It was and is used for dose calculations in preclinical and pet-clinical trials at the biomedical beamline ID17 of the European synchrotron radiation facility in Grenoble, France.

Evaluation of selection criteria for graduate students in radiation therapy.

PubMed

Schneider-Kolsky, Michal; Wright, Caroline; Baird, Marilyn

2006-12-01

Selection of suitable students into graduate medical and specialist health professional courses can be difficult. Historically, selection of students was primarily based on prior academic performance. Recently, however, more emphasis has been placed on considering broader academic backgrounds and personal characteristics and attitudes of students, but no reliable measurement tool is available to predict student success and satisfaction with their choice of profession. The aim of this study was to survey practising radiation therapists in Australia to seek their opinions regarding suitable selection criteria for graduate entry radiation therapy (RT) students in order to optimize selection procedures for future applicants. Four hundred questionnaires were sent to nine RT centres in three states within Australia. All nine clinics participated in the survey and 189 questionnaires were returned. Results show that the majority of radiation therapists place a high level of importance upon a sound knowledge of physics and mathematics, as well as life experience, and agree that a visit to an RT clinic plus an interview comprise important components of the selection process. Humanities, psychology and a psychometric test were not viewed as essential entry requirements. Experienced radiation therapists placed less value on academic performance in the primary degree and were more likely to include an interview as a selection criterion than junior practitioners. Empathy for patients was identified as the most important personal attribute. It is thus recommended that not only cognitive but also personal skills be evaluated during the selection of prospective radiation therapists.

Breast Cancer After Chest Radiation Therapy for Childhood Cancer

PubMed Central

Moskowitz, Chaya S.; Chou, Joanne F.; Wolden, Suzanne L.; Bernstein, Jonine L.; Malhotra, Jyoti; Friedman, Danielle Novetsky; Mubdi, Nidha Z.; Leisenring, Wendy M.; Stovall, Marilyn; Hammond, Sue; Smith, Susan A.; Henderson, Tara O.; Boice, John D.; Hudson, Melissa M.; Diller, Lisa R.; Bhatia, Smita; Kenney, Lisa B.; Neglia, Joseph P.; Begg, Colin B.; Robison, Leslie L.; Oeffinger, Kevin C.

2014-01-01

Purpose The risk of breast cancer is high in women treated for a childhood cancer with chest irradiation. We sought to examine variations in risk resulting from irradiation field and radiation dose. Patients and Methods We evaluated cumulative breast cancer risk in 1,230 female childhood cancer survivors treated with chest irradiation who were participants in the CCSS (Childhood Cancer Survivor Study). Results Childhood cancer survivors treated with lower delivered doses of radiation (median, 14 Gy; range, 2 to 20 Gy) to a large volume (whole-lung field) had a high risk of breast cancer (standardized incidence ratio [SIR], 43.6; 95% CI, 27.2 to 70.3), as did survivors treated with high doses of delivered radiation (median, 40 Gy) to the mantle field (SIR, 24.2; 95% CI, 20.7 to 28.3). The cumulative incidence of breast cancer by age 50 years was 30% (95% CI, 25 to 34), with a 35% incidence among Hodgkin lymphoma survivors (95% CI, 29 to 40). Breast cancer–specific mortality at 5 and 10 years was 12% (95% CI, 8 to 18) and 19% (95% CI, 13 to 25), respectively. Conclusion Among women treated for childhood cancer with chest radiation therapy, those treated with whole-lung irradiation have a greater risk of breast cancer than previously recognized, demonstrating the importance of radiation volume. Importantly, mortality associated with breast cancer after childhood cancer is substantial. PMID:24752044

Endoscopic diode laser therapy for chronic radiation proctitis.

PubMed

Polese, Lino; Marini, Lucia; Rizzato, Roberto; Picardi, Edgardo; Merigliano, Stefano

2018-01-01

The purpose of this study is to determine the effectiveness of endoscopic diode laser therapy in patients presenting rectal bleeding due to chronic radiation proctitis (CRP). A retrospective analysis of CRP patients who underwent diode laser therapy in a single institution between 2010 and 2016 was carried out. The patients were treated by non-contact fibers without sedation in an outpatient setting. Fourteen patients (median age 77, range 73-87 years) diagnosed with CRP who had undergone high-dose radiotherapy for prostatic cancer and who presented with rectal bleeding were included. Six required blood transfusions. Antiplatelet (three patients) and anticoagulant (two patients) therapy was not suspended during the treatments. The patients underwent a median of two sessions; overall, a mean of 1684 J of laser energy per session was used. Bleeding was resolved in 10/14 (71%) patients, and other two patients showed improvement (93%). Only one patient, who did not complete the treatment, required blood transfusions after laser therapy; no complications were noted during or after the procedures. Study findings demonstrated that endoscopic non-contact diode laser treatment is safe and effective in CRP patients, even in those receiving antiplatelet and/or anticoagulant therapy.

Accuracy of Marketing Claims by Providers of Stereotactic Radiation Therapy

PubMed Central

Narang, Amol K.; Lam, Edwin; Makary, Martin A.; DeWeese, Theodore L.; Pawlik, Timothy M.; Pronovost, Peter J.; Herman, Joseph M.

2013-01-01

Purpose: Direct-to-consumer advertising by industry has been criticized for encouraging overuse of unproven therapies, but advertising by health care providers has not been as carefully scrutinized. Stereotactic radiation therapy is an emerging technology that has sparked controversy regarding the marketing campaigns of some manufacturers. Given that this technology is also being heavily advertised on the Web sites of health care providers, the accuracy of providers' marketing claims should be rigorously evaluated. Methods: We reviewed the Web sites of all US hospitals and private practices that provide stereotactic radiation using two leading brands of stereotactic radiosurgery technology. Centers were identified by using data from the manufacturers. Centers without Web sites were excluded. The final study population consisted of 212 centers with online advertisements for stereotactic radiation. Web sites were evaluated for advertisements that were inconsistent with advertising guidelines provided by the American Medical Association. Results: Most centers (76%) had individual pages dedicated to the marketing of their brand of stereotactic technology that frequently contained manufacturer-authored images (50%) or text (55%). Advertising for the treatment of tumors that have not been endorsed by professional societies was present on 66% of Web sites. Centers commonly claimed improved survival (22%), disease control (20%), quality of life (17%), and toxicity (43%) with stereotactic radiation. Although 40% of Web sites championed the center's regional expertise in delivering stereotactic treatments, only 15% of Web sites provided data to support their claims. Conclusion: Provider advertisements for stereotactic radiation were prominent and aggressive. Further investigation of provider advertising, its effects on quality of care, and potential oversight mechanisms is needed. PMID:23633973

Accuracy of marketing claims by providers of stereotactic radiation therapy.

PubMed

Narang, Amol K; Lam, Edwin; Makary, Martin A; Deweese, Theodore L; Pawlik, Timothy M; Pronovost, Peter J; Herman, Joseph M

2013-01-01

Direct-to-consumer advertising by industry has been criticized for encouraging overuse of unproven therapies, but advertising by health care providers has not been as carefully scrutinized. Stereotactic radiation therapy is an emerging technology that has sparked controversy regarding the marketing campaigns of some manufacturers. Given that this technology is also being heavily advertised on the Web sites of health care providers, the accuracy of providers' marketing claims should be rigorously evaluated. We reviewed the Web sites of all U.S. hospitals and private practices that provide stereotactic radiation using two leading brands of stereotactic radiosurgery technology. Centers were identified by using data from the manufacturers. Centers without Web sites were excluded. The final study population consisted of 212 centers with online advertisements for stereotactic radiation. Web sites were evaluated for advertisements that were inconsistent with advertising guidelines provided by the American Medical Association. Most centers (76%) had individual pages dedicated to the marketing of their brand of stereotactic technology that frequently contained manufacturer-authored images (50%) or text (55%). Advertising for the treatment of tumors that have not been endorsed by professional societies was present on 66% of Web sites. Centers commonly claimed improved survival (22%), disease control (20%), quality of life (17%), and toxicity (43%) with stereotactic radiation. Although 40% of Web sites championed the center's regional expertise in delivering stereotactic treatments, only 15% of Web sites provided data to support their claims. Provider advertisements for stereotactic radiation were prominent and aggressive. Further investigation of provider advertising, its effects on quality of care, and potential oversight mechanisms is needed.

Quasi-VMAT in high-grade glioma radiation therapy.

PubMed

Fadda, G; Massazza, G; Zucca, S; Durzu, S; Meleddu, G; Possanzini, M; Farace, P

2013-05-01

To compare a quasi-volumetric modulated arc therapy (qVMAT) with three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) for the treatment of high-grade gliomas. The qVMAT technique is a fast method of radiation therapy in which multiple equispaced beams analogous to those in rotation therapy are radiated in succession. This study included 12 patients with a planning target volume (PTV) that overlapped at least one organ at risk (OAR). 3D-CRT was planned using 2-3 non-coplanar beams, whereby the field-in-field technique (FIF) was used to divide each field into 1-3 subfields to shield the OAR. The qVMAT strategy was planned with 15 equispaced beams and IMRT was planned using 9 beams with a total of 80 segments. Inverse planning for qVMAT and IMRT was performed by direct machine parameter optimization (DMPO) to deliver a homogenous dose distribution of 60 Gy within the PTV and simultaneously limit the dose received by the OARs to the recommended values. Finally, the effect of introducing a maximum dose objective (max. dose < 54 Gy) for a virtual OAR in the form of a 0.5 cm ring around the PTV was investigated. The qVMAT method gave rise to significantly improved PTV95% and conformity index (CI) values in comparison to 3D-CRT (PTV95% = 90.7 % vs. 82.0 %; CI = 0.79 vs. 0.74, respectively). A further improvement was achieved by IMRT (PTV95% = 94.4 %, CI = 0.78). In qVMAT and IMRT, the addition of a 0.5 cm ring around the PTV produced a significant increase in CI (0.87 and 0.88, respectively), but dosage homogeneity within the PTV was considerably reduced (PTV95% = 88.5 % and 92.3 %, respectively). The time required for qVMAT dose delivery was similar to that required using 3D-CRT. These findings suggest that qVMAT should be preferred to 3D-CRT for the treatment of high-grade gliomas. The qVMAT method could be applied in hospitals, for example, which have limited departmental

Stereotactic Body Radiation Therapy for Oligometastatic Prostate Cancer

SciTech Connect

Muldermans, Jonathan L.; Romak, Lindsay B.; Kwon, Eugene D.

Purpose: To review outcomes of patients with oligometastatic prostate cancer (PCa) treated with stereotactic body radiation therapy (SBRT) and to identify variables associated with local failure. Methods and Materials: We retrospectively reviewed records of patients treated with SBRT for oligometastatic PCa. Metastasis control (ie, control of the treated lesion, MC), biochemical progression-free survival, distant progression-free survival, and overall survival were estimated with the Kaplan-Meier method. Results: Sixty-six men with 81 metastatic PCa lesions, 50 of which were castrate-resistant, were included in the analysis. Lesions were in bone (n=74), lymph nodes (n=6), or liver (n=1). Stereotactic body radiation therapy was deliveredmore » in 1 fraction to 71 lesions (88%), at a median dose of 16 Gy (range, 16-24 Gy). The remaining lesions received 30 Gy in 3 fractions (n=6) or 50 Gy in 5 fractions (n=4). Median follow-up was 16 months (range, 3-49 months). Estimated MC at 2 years was 82%. Biochemical progression-free survival, distant progression-free survival, and overall survival were 54%, 45%, and 83%, respectively. On multivariate analysis, only the dose of SBRT was significantly associated with MC; lesions treated with 16 Gy had 58% MC, and those treated with ≥18 Gy had 95% MC at 2 years (P≤.001). At 2 years, MC for lesions treated with 18 Gy (n=21) was 88%. No patient treated with ≥18 Gy in a single fraction or with any multifraction regimen had local failure. Six patients (9%) had grade 1 pain flare, and 2 (3%) had grade 2 pain flare. No grade 2 or greater late toxicities were reported. Conclusions: Stereotactic body radiation therapy for patients with oligometastatic prostate cancer provided optimal metastasis control and acceptable toxicity with doses ≥18 Gy. Biochemical progression-free survival was 54% at 16 months with the inclusion of SBRT in the treatment regimen. Stereotactic body radiation therapy should be considered in

The role of medical physics in prostate cancer radiation therapy.

PubMed

Fiorino, Claudio; Seuntjens, Jan

2016-03-01

Medical physics, both as a scientific discipline and clinical service, hugely contributed and still contributes to the advances in the radiotherapy of prostate cancer. The traditional translational role in developing and safely implementing new technology and methods for better optimizing, delivering and monitoring the treatment is rapidly expanding to include new fields such as quantitative morphological and functional imaging and the possibility of individually predicting outcome and toxicity. The pivotal position of medical physicists in treatment personalization probably represents the main challenge of current and next years and needs a gradual change of vision and training, without losing the traditional and fundamental role of physicists to guarantee a high quality of the treatment. The current focus issue is intended to cover traditional and new fields of investigation in prostate cancer radiation therapy with the aim to provide up-to-date reference material to medical physicists daily working to cure prostate cancer patients. The papers presented in this focus issue touch upon present and upcoming challenges that need to be met in order to further advance prostate cancer radiation therapy. We suggest that there is a smart future for medical physicists willing to perform research and innovate, while they continue to provide high-quality clinical service. However, physicists are increasingly expected to actively integrate their implicitly translational, flexible and high-level skills within multi-disciplinary teams including many clinical figures (first of all radiation oncologists) as well as scientists from other disciplines. Copyright © 2016. Published by Elsevier Ltd.

Radiation therapy and surgery for fibrosarcoma in 33 cats.

PubMed

Cronin, K; Page, R L; Spodnick, G; Dodge, R; Hardie, E N; Price, G S; Ruslander, D; Thrall, D E

1998-01-01

Thirty-three cats with histologically confirmed fibrosarcomas were treated with radiation therapy followed by surgery. The median (95% confidence interval) disease free interval and overall survival were 398 (261,924) and 600 (lower limit 515) days, respectively. There were 19 treatment failures; 11 cats had only local recurrence, 4 cats developed metastatic disease, 3 cats had local recurrence followed by metastasis, and 1 cat developed simultaneous local and distant disease. Twelve cats are alive and disease free. Two cats died without evidence of treatment failure. The presence of tumor cells at the margin of resected tissue after radiation was the only variable which influenced treatment success. The median (95% confidence interval) disease free interval in 5 cats with tumor cells at the margin of the resected specimen was 112 (94,150) days versus 700 (lower limit 328) days for 26 cats with negative tumor margins, p < 0.0001. We did not identify a relationship between tumor volume, number of prior tumor excisions, concomitant use of chemotherapy or various descriptors of the radiation therapy technique and disease free interval.

Radiation therapy in the last month of life.

PubMed

Patel, Anand; Dunmore-Griffith, Jacquelyn; Lutz, Stephen; Johnstone, Peter A S

2014-05-01

We sought to survey a large, multi-center patient sample to better characterize/quantify RT utilization at the end of life. Few objective data exist for radiation therapy (RT) delivery at end of life (EOL). Data were retrieved for all patients receiving RT in calendar year 2010 in the Department of Radiation Oncology at Indiana University (IU) and Howard University (HU) hospitals. Specific attention was made of the group of patients receiving RT in the last 30 days of life. A total of 852 patients received all or part of their RT during 2010 (HU: 139, IU: 713). At time of analysis in early 2012, 179 patients had died (21%). Fifty-four patients (6.3% of total; 30% of expired patients) died within 30 days of receiving their last treatment. Twenty patients (2.3% of total; 11.2% of expired patients) received RT within their last week of life. For both sites, the median time until death from completion of therapy was 12.5 days (range 2-30 days). Radiation in the last month of life is likely to provide minimal palliation or survival benefit. This, coupled with the financial implications, time investment, and physical costs, suggests that physicians and patients should more strongly consider hospice, and minimize duration of palliative RT courses as far as possible. As with chemotherapy, RT utilization at EOL should be considered for collection as an overuse metric.

The role of a prone setup in breast radiation therapy.

PubMed

Huppert, Nelly; Jozsef, Gabor; Dewyngaert, Keith; Formenti, Silvia Chiara

2011-01-01

Most patients undergoing breast conservation therapy receive radiotherapy in the supine position. Historically, prone breast irradiation has been advocated for women with large pendulous breasts in order to decrease acute and late toxicities. With the advent of CT planning, the prone technique has become both feasible and reproducible. It was shown to be advantageous not only for women with larger breasts but in most patients since it consistently reduces, if not eliminates, the inclusion of heart and lung within the field. The prone setup has been accepted as the best localizing position for both MRI and stereotactic biopsy, but its adoption has been delayed in radiotherapy. New technological advances including image-modulated radiation therapy and image-guided radiation therapy have made possible the exploration of accelerated fractionation schemes with a concomitant boost to the tumor bed in the prone position, along with better imaging and verification of reproducibility of patient setup. This review describes some of the available techniques for prone breast radiotherapy and the available experience in their application. The NYU prone breast radiotherapy approach is discussed, including a summary of the results from several prospective trials.

Abdominopelvic kinesiotherapy for pelvic floor muscle training: a tested proposal in different groups.

PubMed

Botelho, Simone; Martinho, Natalia Miguel; Silva, Valéria Regina; Marques, Joseane; Alves, Fabiola Kenia; Riccetto, Cássio

2015-12-01

This video's proposal was to present one of the pelvic floor muscle (PFM) training programs used in our research, and to study the effects of abdominopelvic kinesiotherapy on female PFM function. A total of 82 women participated in this study, 11 nulliparous, 13 primiparous pregnant, 20 primiparous postpartum and 38 postmenopausal women, who were evaluated first by digital palpation, then by either electromyography or vaginal dynamometry to investigate their PFM strength, followed by ICIQ UI-SF and ICIQ-OAB to evaluate urinary symptoms. This intervention protocol lasted for 60 min, three times a week, with a total of 10 sessions, and was supervised by a physiotherapist, using a gym ball, according to Marques and collaborators. A significant increase in PFM strength was observed by digital palpation in all groups. This finding was confirmed by electromyography in both pregnant (p = 0.0001) and postpartum (p = 0.0001) groups, as well as in 20 of the 38 women from the postmenopausal group (p = 0.003) then by vaginal dynamometry (p = 0.02) in the rest of the women (18) from the same group, with a concomitant decrease in urinary symptoms (p < 0.05). The abdominopelvic kinesiotherapy program promotes an increase in pelvic floor muscle strength and a decrease in urinary symptoms.

Palliative care and palliative radiation therapy education in radiation oncology: A survey of US radiation oncology program directors.

PubMed

Wei, Randy L; Colbert, Lauren E; Jones, Joshua; Racsa, Margarita; Kane, Gabrielle; Lutz, Steve; Vapiwala, Neha; Dharmarajan, Kavita V

The purpose of this study was to assess the state of palliative and supportive care (PSC) and palliative radiation therapy (RT) educational curricula in radiation oncology residency programs in the United States. We surveyed 87 program directors of radiation oncology residency programs in the United States between September 2015 and November 2015. An electronic survey on PSC and palliative RT education during residency was sent to all program directors. The survey consisted of questions on (1) perceived relevance of PSC and palliative RT to radiation oncology training, (2) formal didactic sessions on domains of PSC and palliative RT, (3) effective teaching formats for PSC and palliative RT education, and (4) perceived barriers for integrating PSC and palliative RT into the residency curriculum. A total of 57 responses (63%) was received. Most program directors agreed or strongly agreed that PSC (93%) and palliative radiation therapy (99%) are important competencies for radiation oncology residents and fellows; however, only 67% of residency programs had formal educational activities in principles and practice of PSC. Most programs had 1 or more hours of formal didactics on management of pain (67%), management of neuropathic pain (65%), and management of nausea and vomiting (63%); however, only 35%, 33%, and 30% had dedicated lectures on initial management of fatigue, assessing role of spirituality, and discussing advance care directives, respectively. Last, 85% of programs reported having a formal curriculum on palliative RT. Programs were most likely to have education on palliative radiation to brain, bone, and spine, but less likely on visceral, or skin, metastasis. Residency program directors believe that PSC and palliative RT are important competencies for their trainees and support increasing education in these 2 educational domains. Many residency programs have structured curricula on PSC and palliative radiation education, but room for improvement exists in

Cherenkov imaging and biochemical sensing in vivo during radiation therapy

NASA Astrophysics Data System (ADS)

Zhang, Rongxiao

While Cherenkov emission was discovered more than eighty years ago, the potential applications of imaging this during radiation therapy have just recently been explored. With approximately half of all cancer patients being treated by radiation at some point during their cancer management, there is a constant challenge to ensure optimal treatment efficiency is achieved with maximal tumor to normal tissue therapeutic ratio. To achieve this, the treatment process as well as biological information affecting the treatment should ideally be effective and directly derived from the delivery of radiation to the patient. The value of Cherenkov emission imaging was examined here, primarily for visualization of treatment monitoring and then secondarily for Cherenkov-excited luminescence for tissue biochemical sensing within tissue. Through synchronized gating to the short radiation pulses of a linear accelerator (200Hz & 3 micros pulses), and applying a gated intensified camera for imaging, the Cherenkov radiation can be captured near video frame rates (30 frame per sec) with dim ambient room lighting. This procedure, sometimes termed Cherenkoscopy, is readily visualized without affecting the normal process of external beam radiation therapy. With simulation, phantoms and clinical trial data, each application of Cherenkoscopy was examined: i) for treatment monitoring, ii) for patient position monitoring and motion tracking, and iii) for superficial dose imaging. The temporal dynamics of delivered radiation fields can easily be directly imaged on the patient's surface. Image registration and edge detection of Cherenkov images were used to verify patient positioning during treatment. Inter-fraction setup accuracy and intra-fraction patient motion was detectable to better than 1 mm accuracy. Cherenkov emission in tissue opens up a new field of biochemical sensing within the tissue environment, using luminescent agents which can be activated by this light. In the first study of

Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy.

PubMed

Eftekhari, Mohammad; Anbiaei, Robabeh; Zamani, Hanie; Fallahi, Babak; Beiki, Davood; Ameri, Ahmad; Emami-Ardekani, Alireza; Fard-Esfahani, Armaghan; Gholamrezanezhad, Ali; Seid Ratki, Kazem Razavi; Roknabadi, Alireza Momen

2015-01-01

Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right-sided cancer. To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring) were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT) to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions) over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol) was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed) and 36 patients with right-sided cancer (controls)] were enrolled. Dose-volume histogram (DVH) [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46). In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03) and anterolateral (17.1% versus 2.8%, P=0.049) walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS) of>3 was observed in twelve cases (34.3%), while in five of the controls (13.9%),(Odds ratio=1.3). There was no significant difference between the groups regarding left ventricular ejection fraction. The risk of radiation induced myocardial perfusion abnormality in patients treated with CRT on the

Change in Seroma Volume During Whole-Breast Radiation Therapy

SciTech Connect

Sharma, Rajiv; Spierer, Marnee; Mutyala, Subhakar

2009-09-01

Purpose: After breast-conserving surgery, a seroma often forms in the surgical cavity. If not drained, it may affect the volume of tumor bed requiring a boost after whole-breast radiation therapy (WBRT). Our objective was to evaluate the change in seroma volume that occurs during WBRT, before boost planning. Methods and Materials: A retrospective review was performed of women receiving breast-conserving therapy with evidence of seroma at the time of WBRT planning. Computed tomography (CT) simulation was performed before WBRT and before the tumor bed boost. All patients received either a hypofractionated (42.4 Gy/16 fraction + 9.6 Gy/4 fraction boost) ormore » standard fractionated (50.4 Gy/28 fraction + 10 Gy/5 fraction boost) regimen. Seroma volumes were contoured and compared on CT at the time of WBRT simulation and tumor bed boost planning. Results: Twenty-four patients with evidence of seroma were identified and all patients received WBRT without drainage of the seroma. Mean seroma volume before WBRT and at boost planning were significantly different at 65.7 cm{sup 3} (SD, 50.5 cm{sup 3}) and 35.6 cm{sup 3} (SD, 24.8 cm{sup 3}), respectively (p < 0.001). Mean and median reduction in seroma volume during radiation were 39.6% (SD, 23.8%) and 46.2% (range, 10.7-76.7%), respectively. Fractionation schedule was not correlated with change in seroma volume. Length of time from surgery to start of radiation therapy showed an inverse correlation with change in seroma volume (Pearson correlation r = -0.53, p < 0.01). Conclusions: The volume of seroma changes significantly during WBRT. Consequently, the accuracy of breast boost planning is likely affected, as is the volume of normal breast tissue irradiated. CT-based boost planning before boost irradiation is suggested to ensure appropriate coverage.« less

21 CFR 892.5770 - Powered radiation therapy patient support assembly.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Powered radiation therapy patient support assembly. 892.5770 Section 892.5770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... therapy patient support assembly. (a) Identification. A powered radiation therapy patient support assembly...

21 CFR 892.5770 - Powered radiation therapy patient support assembly.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Powered radiation therapy patient support assembly. 892.5770 Section 892.5770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... therapy patient support assembly. (a) Identification. A powered radiation therapy patient support assembly...

21 CFR 892.5770 - Powered radiation therapy patient support assembly.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Powered radiation therapy patient support assembly. 892.5770 Section 892.5770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... therapy patient support assembly. (a) Identification. A powered radiation therapy patient support assembly...

21 CFR 892.5770 - Powered radiation therapy patient support assembly.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Powered radiation therapy patient support assembly. 892.5770 Section 892.5770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... therapy patient support assembly. (a) Identification. A powered radiation therapy patient support assembly...

Linear algebraic methods applied to intensity modulated radiation therapy.

PubMed

Crooks, S M; Xing, L

2001-10-01

Methods of linear algebra are applied to the choice of beam weights for intensity modulated radiation therapy (IMRT). It is shown that the physical interpretation of the beam weights, target homogeneity and ratios of deposited energy can be given in terms of matrix equations and quadratic forms. The methodology of fitting using linear algebra as applied to IMRT is examined. Results are compared with IMRT plans that had been prepared using a commercially available IMRT treatment planning system and previously delivered to cancer patients.

TH-E-202-00: PET for Radiation Therapy

SciTech Connect

NONE

PET/CT is a very important imaging tool in the management of oncology patients. PET/CT has been applied for treatment planning and response evaluation in radiation therapy. This educational session will discuss: Pitfalls and remedies in PET/CT imaging for RT planning The use of hypoxia PET imaging for radiotherapy PET for tumor response evaluation The first presentation will address the issue of mis-registration between the CT and PET images in the thorax and the abdomen. We will discuss the challenges of respiratory gating and introduce an average CT technique to improve the registration for dose calculation and image-guidance in radiation therapy.more » The second presentation will discuss the use of hypoxia PET Imaging for radiation therapy. We will discuss various hypoxia radiotracers, the choice of clinical acquisition protocol (in particular a single late static acquisition versus a dynamic acquisition), and the compartmental modeling with different transfer rate constants explained. We will demonstrate applications of hypoxia imaging for dose escalation/de-escalation in clinical trials. The last presentation will discuss the use of PET/CT for tumor response evaluation. We will discuss anatomic response assessment vs. metabolic response assessment, visual evaluation and semi-quantitative evaluation, and limitations of current PET/CT assessment. We will summarize clinical trials using PET response in guiding adaptive radiotherapy. Finally, we will summarize recent advancements in PET/CT radiomics and non-FDG PET tracers for response assessment. Learning Objectives: Identify the causes of mis-registration of CT and PET images in PET/CT, and review the strategies to remedy the issue. Understand the basics of PET imaging of tumor hypoxia (radiotracers, how PET measures the hypoxia selective uptake, imaging protocols, applications in chemo-radiation therapy). Understand the basics of dynamic PET imaging, compartmental modeling and parametric images. Understand

Oral histoplasmosis after radiation therapy for laryngeal squamous cell carcinoma.

PubMed

Ezzedine, Khaled; Accoceberry, Isabelle; Malvy, Denis

2007-05-01

Histoplasmosis is a usually asymptomatic deep fungal infection of tropical origin with respiratory entry and possible oral, pharyngeal, or metastatic localization. The condition represents an important imported systemic mycosis with oral involvement. We report the case of a patient who developed an oropharyngeal reactivation of a latent Histoplasma infection after receiving local antitumoral radiation therapy of the neck. H capsulatum was shown to be present in the lesion by both histopathology and staining, and was deduced to be the causative organism of the disease.

Obstructive ureteropathy following radiation therapy for carcinoma of the cervix

SciTech Connect

Parliament, M.; Genest, P.; Girard, A.

1989-05-01

Between January 1959 and December 1986, 10 of 328 patients (3%) treated with curative intent using primary radiation therapy for carcinoma of the cervix developed obstructive ureteropathy due to fibrosis. The mean age of the patients with obstructive ureteropathy was 45 years and the median time to obstruction was 26 months. The obstruction was unilateral in 8 cases and involved the parametrial portion of the ureter in at least 5 cases. No predisposing risk factor was found to be associated with the development of obstructive ureteropathy. After corrective surgery, renal function remained normal in 8 patients, and resolution of themore » hydronephrosis occurred in 4 patients.« less

Carcinoma of the cervix, stage III. Results of radiation therapy.

PubMed

Montana, G S; Fowler, W C; Varia, M A; Walton, L A; Mack, Y; Shemanski, L

1986-01-01

From April 1969 through December 1980, 203 patients with Stage III epidermoid carcinoma of the cervix were treated with radiation therapy with curative intent. The disease-free survival at 2, 5, and 10 years was 50%, 33%, and 27%, respectively. The survival was better for patients with Stage IIIB disease than for those with Stage IIIA disease. Eighty-eight patients were treated with external beam therapy only, and 115 received external beam and brachytherapy. The disease-free survival was better for the combination therapy group initially, but this difference was not sustained beyond 5 years. One hundred eight patients experienced recurrence within the irradiated field, for a locoregional recurrence rate of 53%. Twenty-seven patients had complications (13%). The complications were mild in 13 patients, moderate in 4 patients, and severe in 10 patients. A study was made of the relationship of the dose to Point A and the occurrence of complications. Similar analyses were made of the bladder and rectal doses and the subsequent occurrence of urinary and intestinal complications. In these analyses, the mean dose to Point A and the critical organs was higher for the groups of patients with complications than for those patients without complications. This relationship was also observed when the patients were stratified for treatment with either external beam plus brachytherapy or external beam therapy alone.

Delineation of Supraclavicular Target Volumes in Breast Cancer Radiation Therapy

SciTech Connect

Brown, Lindsay C.; Diehn, Felix E.; Boughey, Judy C.

Purpose: To map the location of gross supraclavicular metastases in patients with breast cancer, in order to determine areas at highest risk of harboring subclinical disease. Methods and Materials: Patients with axial imaging of gross supraclavicular disease were identified from an institutional breast cancer registry. Locations of the metastatic lymph nodes were transferred onto representative axial computed tomography images of the supraclavicular region and compared with the Radiation Therapy Oncology Group (RTOG) breast cancer atlas for radiation therapy planning. Results: Sixty-two patients with 161 supraclavicular nodal metastases were eligible for study inclusion. At the time of diagnosis, 117 nodal metastasesmore » were present in 44 patients. Forty-four nodal metastases in 18 patients were detected at disease recurrence, 4 of whom had received prior radiation to the supraclavicular fossa. Of the 161 nodal metastases, 95 (59%) were within the RTOG consensus volume, 4 nodal metastases (2%) in 3 patients were marginally within the volume, and 62 nodal metastases (39%) in 30 patients were outside the volume. Supraclavicular disease outside the RTOG consensus volume was located in 3 regions: at the level of the cricoid and thyroid cartilage (superior to the RTOG volume), in the posterolateral supraclavicular fossa (posterolateral to the RTOG volume), and in the lateral low supraclavicular fossa (lateral to the RTOG volume). Only women with multiple supraclavicular metastases had nodal disease that extended superiorly to the level of the thyroid cartilage. Conclusions: For women with risk of harboring subclinical supraclavicular disease warranting the addition of supraclavicular radiation, coverage of the posterior triangle and the lateral low supraclavicular region should be considered. For women with known supraclavicular disease, extension of neck coverage superior to the cricoid cartilage may be warranted.« less

Monitoring the radiation dose to a multiprogrammable pacemaker during radical radiation therapy: A case report

SciTech Connect

Muller-Runkel, R.; Orsolini, G.; Kalokhe, U.P.

1990-11-01

Multiprogrammable pacemakers, using complimentary metaloxide semiconductor (CMOS) circuitry, may fail during radiation therapy. We report about a patient who received 6,400 cGy for unresectable carcinoma of the left lung. In supine treatment position, arms raised above the head, the pacemaker was outside the treated area by a margin of at least 1 cm, shielded by cerrobend blocking mounted on a tray. From thermoluminescent dosimeter (TLD) measurements, we estimate that the pacemaker received 620 cGy in scatter doses. Its function was monitored before, during, and after completion of radiation therapy. The pacemaker was functioning normally until the patient's death 5 monthsmore » after completion of treatment. The relevant electrocardiograms (ECGs) are presented.« less

Potency preservation following stereotactic body radiation therapy for prostate cancer

PubMed Central

2013-01-01

Background Erectile dysfunction after prostate radiation therapy remains an ongoing challenge and critical quality of life issue. Given the higher dose of radiation per fraction using stereotactic body radiation therapy (SBRT) there is concern that post-SBRT impotency would be higher than conventional radiation therapy approaches. This study sought to evaluate potency preservation and sexual function following SBRT for prostate cancer. Methods Between February 2008 and March 2011, 216 men with clinically localized prostate cancer were treated definitively with SBRT monotherapy at Georgetown University Hospital. Potency was defined as the ability to have an erection firm enough for intercourse with or without sexual aids while sexual activity was defined as the ability to have an erection firm enough for masturbation and foreplay. Patients who received androgen deprivation therapy (ADT) were excluded from this study. Ninety-seven hormone-naïve men were identified as being potent at the initiation of therapy and were included in this review. All patients were treated to 35–36.25 Gy in 5 fractions delivered with the CyberKnife Radiosurgical System (Accuray). Prostate specific antigen (PSA) and total testosterone levels were obtained pre-treatment, every 3 months for the first year and every 6 months for the subsequent year. Sexual function was assessed with the Sexual Health Inventory for Men (SHIM), the Expanded Prostate Index Composite (EPIC)-26 and Utilization of Sexual Medication/Device questionnaires at baseline and all follow-up visits. Results Ninety-seven men (43 low-, 50 intermediate- and 4 high-risk) at a median age of 68 years (range, 48–82 years) received SBRT. The median pre-treatment PSA was 5.9 ng/ml and the minimum follow-up was 24 months. The median pre-treatment total serum testosterone level was 11.4 nmol/L (range, 4.4-27.9 nmol/L). The median baseline SHIM was 22 and 36% of patients utilized sexual aids prior to treatment. Although

Mertk on tumor macrophages is a therapeutic target to prevent tumor recurrence following radiation therapy

PubMed Central

Crittenden, Marka R.; Baird, Jason; Friedman, David; Savage, Talicia; Uhde, Lauren; Alice, Alejandro; Cottam, Benjamin; Young, Kristina; Newell, Pippa; Nguyen, Cynthia; Bambina, Shelly; Kramer, Gwen; Akporiaye, Emmanuel; Malecka, Anna; Jackson, Andrew; Gough, Michael J.

2016-01-01

Radiation therapy provides a means to kill large numbers of cancer cells in a controlled location resulting in the release of tumor-specific antigens and endogenous adjuvants. However, by activating pathways involved in apoptotic cell recognition and phagocytosis, irradiated cancer cells engender suppressive phenotypes in macrophages. We demonstrate that the macrophage-specific phagocytic receptor, Mertk is upregulated in macrophages in the tumor following radiation therapy. Ligation of Mertk on macrophages results in anti-inflammatory cytokine responses via NF-kB p50 upregulation, which in turn limits tumor control following radiation therapy. We demonstrate that in immunogenic tumors, loss of Mertk is sufficient to permit tumor cure following radiation therapy. However, in poorly immunogenic tumors, TGFb inhibition is also required to result in tumor cure following radiation therapy. These data demonstrate that Mertk is a highly specific target whose absence permits tumor control in combination with radiation therapy. PMID:27602953

Bioluminescence Tomography–Guided Radiation Therapy for Preclinical Research

SciTech Connect

Zhang, Bin; Wang, Ken Kang-Hsin, E-mail: kwang27@jhmi.edu; Yu, Jingjing

Purpose: In preclinical radiation research, it is challenging to localize soft tissue targets based on cone beam computed tomography (CBCT) guidance. As a more effective method to localize soft tissue targets, we developed an online bioluminescence tomography (BLT) system for small-animal radiation research platform (SARRP). We demonstrated BLT-guided radiation therapy and validated targeting accuracy based on a newly developed reconstruction algorithm. Methods and Materials: The BLT system was designed to dock with the SARRP for image acquisition and to be detached before radiation delivery. A 3-mirror system was devised to reflect the bioluminescence emitted from the subject to a stationarymore » charge-coupled device (CCD) camera. Multispectral BLT and the incomplete variables truncated conjugate gradient method with a permissible region shrinking strategy were used as the optimization scheme to reconstruct bioluminescent source distributions. To validate BLT targeting accuracy, a small cylindrical light source with high CBCT contrast was placed in a phantom and also in the abdomen of a mouse carcass. The center of mass (CoM) of the source was recovered from BLT and used to guide radiation delivery. The accuracy of the BLT-guided targeting was validated with films and compared with the CBCT-guided delivery. In vivo experiments were conducted to demonstrate BLT localization capability for various source geometries. Results: Online BLT was able to recover the CoM of the embedded light source with an average accuracy of 1 mm compared to that with CBCT localization. Differences between BLT- and CBCT-guided irradiation shown on the films were consistent with the source localization revealed in the BLT and CBCT images. In vivo results demonstrated that our BLT system could potentially be applied for multiple targets and tumors. Conclusions: The online BLT/CBCT/SARRP system provides an effective solution for soft tissue targeting, particularly for small

Radiation-Induced Leukemia at Doses Relevant to Radiation Therapy: Modeling Mechanisms and Estimating Risks

NASA Technical Reports Server (NTRS)

Shuryak, Igor; Sachs, Rainer K.; Hlatky, Lynn; Mark P. Little; Hahnfeldt, Philip; Brenner, David J.

2006-01-01

Because many cancer patients are diagnosed earlier and live longer than in the past, second cancers induced by radiation therapy have become a clinically significant issue. An earlier biologically based model that was designed to estimate risks of high-dose radiation induced solid cancers included initiation of stem cells to a premalignant state, inactivation of stem cells at high radiation doses, and proliferation of stem cells during cellular repopulation after inactivation. This earlier model predicted the risks of solid tumors induced by radiation therapy but overestimated the corresponding leukemia risks. Methods: To extend the model to radiation-induced leukemias, we analyzed in addition to cellular initiation, inactivation, and proliferation a repopulation mechanism specific to the hematopoietic system: long-range migration through the blood stream of hematopoietic stem cells (HSCs) from distant locations. Parameters for the model were derived from HSC biologic data in the literature and from leukemia risks among atomic bomb survivors v^ ho were subjected to much lower radiation doses. Results: Proliferating HSCs that migrate from sites distant from the high-dose region include few preleukemic HSCs, thus decreasing the high-dose leukemia risk. The extended model for leukemia provides risk estimates that are consistent with epidemiologic data for leukemia risk associated with radiation therapy over a wide dose range. For example, when applied to an earlier case-control study of 110000 women undergoing radiotherapy for uterine cancer, the model predicted an excess relative risk (ERR) of 1.9 for leukemia among women who received a large inhomogeneous fractionated external beam dose to the bone marrow (mean = 14.9 Gy), consistent with the measured ERR (2.0, 95% confidence interval [CI] = 0.2 to 6.4; from 3.6 cases expected and 11 cases observed). As a corresponding example for brachytherapy, the predicted ERR of 0.80 among women who received an inhomogeneous low

Sexual function after surgical and radiation therapy for cervical carcinoma

SciTech Connect

Seibel, M.; Freeman, M.G.; Graves, W.L.

One hundred women treated for carcinoma of the cervix were interviewed more than one year later to establish the effects of radiation or surgical therapy on sexual function. Forty-three had received irradiation, 44 nonradical surgery, six combined surgery and irradiation, and seven radical surgery. The irradiation and nonradical surgery groups were each further subdivided into subgroups of patients aged 30 to 49 for age-controlled comparison. Patients in the irradiation group had statistically significant decreases in sexual enjoyment, ability to attain orgasm, coital opportunity, frequency of intercourse, and coital desire. The group who had nonradical surgical procedures had no significant changemore » in sexual function after treatment. Similar results were found in both age-controlled subgroups, eliminating age as a major etiologic factor. Marked vaginal alterations were recorded in the majority of irradiated patients, but were not present among the groups treated with nonradical surgery. The vaginal changes alone could not be held accountable for the significant decrease in sexual function among women who received pelvic irradiation. The origin of decreased sexual desire after radiation therapy is complex, and not yet completely understood. We propose therapeutic programs to help women deal with the emotional and physical consequences of pelvic irradiation.« less

Quality assurance of intensity-modulated radiation therapy.

PubMed

Palta, Jatinder R; Liu, Chihray; Li, Jonathan G

2008-01-01

The current paradigm for the quality assurance (QA) program for intensity-modulated radiation therapy (IMRT) includes QA of the treatment planning system, QA of the delivery system, and patient-specific QA. Although the IMRT treatment planning and delivery system is the same as for conventional three-dimensional conformal radiation therapy, it has more parameters to coordinate and verify. Because of complex beam intensity modulation, each IMRT field often includes many small irregular off-axis fields, resulting in isodose distributions for each IMRT plan that are more conformal than those from conventional treatment plans. Therefore, these features impose a new and more stringent set of QA requirements for IMRT planning and delivery. The generic test procedures to validate dose calculation and delivery accuracy for both treatment planning and IMRT delivery have to be customized for each type of IMRT planning and delivery strategy. The rationale for such an approach is that the overall accuracy of IMRT delivery is incumbent on the piecewise uncertainties in both the planning and delivery processes. The end user must have well-defined evaluation criteria for each element of the planning and delivery process. Such information can potentially be used to determine a priori the accuracy of IMRT planning and delivery.

Image-guided radiation therapy in lymphoma management

PubMed Central

Eng, Tony

2015-01-01

Image-guided radiation therapy (IGRT) is a process of incorporating imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), Positron emission tomography (PET), and ultrasound (US) during radiation therapy (RT) to improve treatment accuracy. It allows real-time or near real-time visualization of anatomical information to ensure that the target is in its position as planned. In addition, changes in tumor volume and location due to organ motion during treatment can be also compensated. IGRT has been gaining popularity and acceptance rapidly in RT over the past 10 years, and many published data have been reported on prostate, bladder, head and neck, and gastrointestinal cancers. However, the role of IGRT in lymphoma management is not well defined as there are only very limited published data currently available. The scope of this paper is to review the current use of IGRT in the management of lymphoma. The technical and clinical aspects of IGRT, lymphoma imaging studies, the current role of IGRT in lymphoma management and future directions will be discussed. PMID:26484299

Inflammatory bowel diseases activity in patients undergoing pelvic radiation therapy.

PubMed

Annede, Pierre; Seisen, Thomas; Klotz, Caroline; Mazeron, Renaud; Maroun, Pierre; Petit, Claire; Deutsch, Eric; Bossi, Alberto; Haie-Meder, Christine; Chargari, Cyrus; Blanchard, Pierre

2017-02-01

Few studies with contradictory results have been published on the safety of pelvic radiation therapy (RT) in patients with inflammatory bowel disease (IBD). From 1989 to 2015, a single center retrospective analysis was performed including all IBD patients who received pelvic external beam radiation therapy (EBRT) or brachytherapy (BT) for a pelvic malignancy. Treatment characteristics, IBD activity and gastrointestinal (GI) toxicity were examined. Overall, 28 patients with Crohn's disease (CD) (n=13) or ulcerative colitis (n=15) were included in the present study. Median follow-up time after irradiation was 5.9 years. Regarding IBD activity, only one and two patients experienced a severe episode within and after 6 months of follow-up, respectively. Grade 3/4 acute GI toxicity occurred in 3 (11%) patients, whereas one (3.6%) patient experienced late grade 3/4 GI toxicity. Only patients with rectal IBD location (P=0.016) or low body mass index (BMI) (P=0.012) experienced more severe IBD activity within or after 6 months following RT, respectively. We report an acceptable tolerance of RT in IBD patients with pelvic malignancies. Specifically, a low risk of uncontrolled flare-up was observed.

Outcome and Prognostic Factors of Radiation Therapy for Medulloblastoma

SciTech Connect

Rieken, Stefan, E-mail: Stefan.Rieken@med.uni-heidelberg.de; Mohr, Angela; Habermehl, Daniel

2011-11-01

Purpose: To investigate treatment outcome and prognostic factors after radiation therapy in patients with medulloblastomas (MB). Methods and Materials: Sixty-six patients with histologically confirmed MB were treated at University Hospital of Heidelberg between 1985 and 2009. Forty-two patients (64%) were pediatric ({<=}18 years), and 24 patients (36%) were adults. Tumor resection was performed in all patients and was complete in 47%. All patients underwent postoperative craniospinal irradiation (CSI) delivering a median craniospinal dose of 35.5 Gy with additional boosts to the posterior fossa up to 54.0 Gy. Forty-seven patients received chemotherapy, including 21 in whom chemotherapy was administered before CSI.more » Statistical analysis was performed using the log-rank test and the Kaplan-Meier method. Results: Median follow-up was 93 months. Overall survival (OS) and local and distant progression-free survival (LPFS and DPFS) were 73%, 62%, and 77% at 60 months. Both local and distant recurrence predisposed for significantly reduced OS. Macroscopic complete tumor resection, desmoplastic histology and early initiation of postoperative radiation therapy within 28 days were associated with improved outcome. The addition of chemotherapy did not improve survival rates. Toxicity was moderate. Conclusions: Complete resection of MB followed by CSI yields long survival rates in both children and adults. Delayed initiation of CSI is associated with poor outcome. Desmoplastic histology is associated with improved survival. The role of chemotherapy, especially in the adult population, must be further investigated in clinical studies.« less

Predicting Behavioral Problems in Craniopharyngioma Survivors after Conformal Radiation Therapy

PubMed Central

Dolson, Eugenia P.; Conklin, Heather M.; Li, Chenghong; Xiong, Xiaoping; Merchant, Thomas E.

2009-01-01

Background Although radiation therapy is a primary treatment for craniopharyngioma, it can exacerbate existing problems related to the tumor and pre-irradiation management. Survival is often marked by neurologic deficits, panhypopituitarism, diabetes insipidus, cognitive deficiencies and behavioral and social problems. Procedure The Achenbach Child Behavior Checklist (CBCL) was used to evaluate behavioral and social problems during the first five years of follow-up in 27 patients with craniopharyngioma treated with conformal radiation therapy. Results All group averages for the CBCL scales were within the age-typical range at pre-irradiation baseline. Extent of surgical resection was implicated in baseline differences for the Internalizing, Externalizing, Behavior Problem and Social scores. Significant longitudinal changes were found in Internalizing, Externalizing, Behavior Problem and School scores that correlated with tumor and treatment related factors. Conclusions The most common variables implicated in post-irradiation behavioral and social problems were CSF shunting, presence of an Ommaya reservoir, diabetes insipidus, and low pre-irradiation growth hormone levels. PMID:19191345

A systematic overview of radiation therapy effects in oesophageal cancer.

PubMed

Ask, Anders; Albertsson, Maria; Järhult, Johannes; Cavallin-Ståhl, Eva

2003-01-01

A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for oesophageal cancer is based on data from 42 randomized trials and 2 meta-analyses. A total of 44 scientific articles are included, involving 5 772 patients. The conclusions reached can be summarized as follows: There is fairly strong evidence that preoperative radiotherapy does not improve the survival in patients with potentially resectable oesophageal cancer. There is moderate evidence that preoperative chemo-radiotherapy has no beneficial impact on the survival of patients with potentially resectable oesophageal cancer. There is no scientific evidence that postoperative radiotherapy improves survival in patients with resectable oesophageal cancer. The documentation is, however, poor, consisting of only three randomized trials. There is fairly strong evidence that concomitant (but not sequential) chemo-radiotherapy gives significantly better survival rate than radiotherapy alone in inoperable oesophageal cancer. The results of the reported clinical trials are, however, conflicting, and no solid conclusion can be drawn. Hyperfractionated radiotherapy has been compared with conventionally fractionated radiotherapy in two randomized studies with conflicting results and no firm conclusion can be drawn.

[Staffing levels in medical radiation physics in radiation therapy in Germany. Summary of a questionnaire].

PubMed

Leetz, Hans-Karl; Eipper, Hermann Hans; Gfirtner, Hans; Schneider, Peter; Welker, Klaus

2003-10-01

To get a general idea of the actual staffing level situation in medical radiation physics in 1999 a survey was carried out by the task-group "Personalbedarf" of Deutsche Gesellschaft für Medizinische Physik (DGMP) among all DGMP-members who are active in this field. Main components for equipment and activities are defined in Report 8 and 10 of DGMP for staffing requirements in medical radiation physics. 322 forms were sent out, 173 of them have been evaluated. From the answers regarding equipment and activities numbers for staff are calculated by the methods given in Report 8 and 10 for this spot check target and compared with effective staffing levels. The data of the spot check are then extrapolated on total Germany. The result is a calculated deficit of 865 medical physicists for the whole physics staff, 166 of them in radiation therapy. From the age distribution of DGMP-members and the calculated deficit resulted a training capacity of about 100 medical physicists at all per year (19 in radiation therapy) if the deficit shall be cut back in 10 years.

Imaging Changes in Pediatric Intracranial Ependymoma Patients Treated With Proton Beam Radiation Therapy Compared to Intensity Modulated Radiation Therapy

SciTech Connect

Gunther, Jillian R.; Sato, Mariko; Chintagumpala, Murali

Purpose: The clinical significance of magnetic resonance imaging (MRI) changes after radiation therapy (RT) in children with ependymoma is not well defined. We compared imaging changes following proton beam radiation therapy (PBRT) to those after photon-based intensity modulated RT (IMRT). Methods and Materials: Seventy-two patients with nonmetastatic intracranial ependymoma who received postoperative RT (37 PBRT, 35 IMRT) were analyzed retrospectively. MRI images were reviewed by 2 neuroradiologists. Results: Sixteen PBRT patients (43%) developed postradiation MRI changes at 3.8 months (median) with resolution by 6.1 months. Six IMRT patients (17%) developed changes at 5.3 months (median) with 8.3 months to resolution. Mean age at radiation wasmore » 4.4 and 6.9 years for PBRT and IMRT, respectively (P=.06). Age at diagnosis (>3 years) and time of radiation (≥3 years) was associated with fewer imaging changes on univariate analysis (odds ratio [OR]: 0.35, P=.048; OR: 0.36, P=.05). PBRT (compared to IMRT) was associated with more frequent imaging changes, both on univariate (OR: 3.68, P=.019) and multivariate (OR: 3.89, P=.024) analyses. Seven (3 IMRT, 4 PBRT) of 22 patients with changes had symptoms requiring intervention. Most patients were treated with steroids; some PBRT patients also received bevacizumab and hyperbaric oxygen therapy. None of the IMRT patients had lasting deficits, but 2 patients died from recurrent disease. Three PBRT patients had persistent neurological deficits, and 1 child died secondarily to complications from radiation necrosis. Conclusions: Postradiation MRI changes are more common with PBRT and in patients less than 3 years of age at diagnosis and treatment. It is difficult to predict causes for development of imaging changes that progress to clinical significance. These changes are usually self-limiting, but some require medical intervention, especially those involving the brainstem.« less

Hyperbaric Oxygen Therapy for Radiation-Induced Cystitis and Proctitis

SciTech Connect

Oliai, Caspian; Fisher, Brandon; Jani, Ashish

Purpose: To provide a retrospective analysis of the efficacy of hyperbaric oxygen therapy (HBOT) for treating hemorrhagic cystitis (HC) and proctitis secondary to pelvic- and prostate-only radiotherapy. Methods and Materials: Nineteen patients were treated with HBOT for radiation-induced HC and proctitis. The median age at treatment was 66 years (range, 15-84 years). The range of external-beam radiation delivered was 50.0-75.6 Gy. Bleeding must have been refractory to other therapies. Patients received 100% oxygen at 2.0 atmospheres absolute pressure for 90-120 min per treatment in a monoplace chamber. Symptoms were retrospectively scored according to the Late Effects of Normal Tissues-Subjective, Objective,more » Management, Analytic (LENT-SOMA) scale to evaluate short-term efficacy. Recurrence of hematuria/hematochezia was used to assess long-term efficacy. Results: Four of the 19 patients were lost to follow-up. Fifteen patients were evaluated and received a mean of 29.8 dives: 11 developed HC and 4 proctitis. All patients experienced a reduction in their LENT-SOMA score. After completion of HBOT, the mean LENT-SOMA score was reduced from 0.78 to 0.20 in patients with HC and from 0.66 to 0.26 in patients with proctitis. Median follow-up was 39 months (range, 7-70 months). No cases of hematuria were refractory to HBOT. Complete resolution of hematuria was seen in 81% (n = 9) and partial response in 18% (n = 2). Recurrence of hematuria occurred in 36% (n = 4) after a median of 10 months. Complete resolution of hematochezia was seen in 50% (n = 2), partial response in 25% (n = 1), and refractory bleeding in 25% (n = 1). Conclusions: Hyperbaric oxygen therapy is appropriate for radiation-induced HC once less time-consuming therapies have failed to resolve the bleeding. In these conditions, HBOT is efficacious in the short and long term, with minimal side effects.« less

Radiation exposure and radiation protection of the physician in iodine-131 Lipiodol therapy of liver tumours.

PubMed

Risse, J H; Ponath, C; Palmedo, H; Menzel, C; Grünwald, F; Biersack, H J

2001-07-01

Intra-arterial iodine-131 labelled Lipiodol therapy for liver cancer has been investigated for safety and efficacy over a number of years, but data on radiation exposure of personnel have remained unavailable to date. The aim of this study was to assess the radiation exposure of the physician during intra-arterial 131I-Lipiodol therapy for liver malignancies and to develop appropriate radiation protection measures and equipment. During 20 intra-arterial administrations of 131I-Lipiodol (1110-1924 MBq), radiation dose equivalents (RDE) to the whole body, fingers and eyes of the physician were determined for (a) conventional manual administration through a shielded syringe, (b) administration with an automatic injector and (c) administration with a lead container developed in-house. Administration by syringe resulted in a finger RDE of 19.5 mSv, an eye RDE of 130-140 microSv, and a whole-body RDE of 108-119 microSv. The injector reduced the finger RDE to 5 mSv. With both technique (a) and technique (b), contamination of angiography materials was observed. The container allowed safe transport and administration of the radiopharmaceutical from 4 m distance and reduced the finger RDE to <3 microSv and the eye RDE to <1 microSv during injection. During femoral artery compression, radiation exposure to the fingers reached 170 microSv, but the whole-body dose could be reduced from a mean RDE of 114 microSv to 14 microSv. No more contamination occurred. In conclusion, radiation exposure was high when 131I-Lipiodol was administered by syringe or injector, but was significantly reduced with the lead container.

The concept and evolution of involved site radiation therapy for lymphoma.

PubMed

Specht, Lena; Yahalom, Joachim

2015-10-01

We describe the development of radiation therapy for lymphoma from extended field radiotherapy of the past to modern conformal treatment with involved site radiation therapy based on advanced imaging, three-dimensional treatment planning and advanced treatment delivery techniques. Today, radiation therapy is part of the multimodality treatment of lymphoma, and the irradiated tissue volume is much smaller than before, leading to highly significant reductions in the risks of long-term complications.

Enhancement of Radiation Therapy in Prostate Cancer by DNA-PKcs Inhibitor

DTIC Science & Technology

2012-07-01

Award Number: W81XWH-11-1-0270 TITLE: Enhancement of Radiation Therapy in Prostate Cancer by DNA-PKcs Inhibitor PRINCIPAL INVESTIGATOR...TITLE AND SUBTITLE Enhancement of Radiation Therapy in Prostate Cancer by 5a. CONTRACT NUMBER DNA-PKcs Inhibitor 5b. GRANT NUMBER W81XWH-11-1-0270...the treatment of localized prostate cancer . However, a proportion of locally advanced cancers develop radiation resistance and recur after therapy

Therapeutic Implications for Overcoming Radiation Resistance in Cancer Therapy

PubMed Central

Kim, Byeong Mo; Hong, Yunkyung; Lee, Seunghoon; Liu, Pengda; Lim, Ji Hong; Lee, Yong Heon; Lee, Tae Ho; Chang, Kyu Tae; Hong, Yonggeun

2015-01-01

Ionizing radiation (IR), such as X-rays and gamma (γ)-rays, mediates various forms of cancer cell death such as apoptosis, necrosis, autophagy, mitotic catastrophe, and senescence. Among them, apoptosis and mitotic catastrophe are the main mechanisms of IR action. DNA damage and genomic instability contribute to IR-induced cancer cell death. Although IR therapy may be curative in a number of cancer types, the resistance of cancer cells to radiation remains a major therapeutic problem. In this review, we describe the morphological and molecular aspects of various IR-induced types of cell death. We also discuss cytogenetic variations representative of IR-induced DNA damage and genomic instability. Most importantly, we focus on several pathways and their associated marker proteins responsible for cancer resistance and its therapeutic implications in terms of cancer cell death of various types and characteristics. Finally, we propose radiation-sensitization strategies, such as the modification of fractionation, inflammation, and hypoxia and the combined treatment, that can counteract the resistance of tumors to IR. PMID:26569225

Stereotactic multibeam radiation therapy system in a PACS environment

NASA Astrophysics Data System (ADS)

Fresne, Francoise; Le Gall, G.; Barillot, Christian; Gibaud, Bernard; Manens, Jean-Pierre; Toumoulin, Christine; Lemoine, Didier; Chenal, C.; Scarabin, Jean-Marie

1991-05-01

A Multibeam radiation therapy treatment is a non-invasive technique devoted to treat a lesion within the cerebral medium by focusing photon-beams on the same target from a high number of entrance points. We present here a computer assisted dosimetric planning procedure which includes: (1) an analysis module to define the target volume by using 2D and 3D displays, (2) a planing module to issue a treatment strategy including the dosimetric simulations and (3) a treatment module setting up the parameters to order the robotized treatment system (i.e. chair- framework, radiation unit machine). Another important feature of this system is its connection to the PACS system SIRENE settled in the University hospital of Rennes which makes possible the archiving and the communication of the multimodal images (CT, MRI, Angiography) used by this application. The corporate use of stereotactic methods and the multimodality imagery ensures spatial coherence and makes the target definition and the cognition of the structures environment more accurate. The dosimetric planning suited to the spatial reference (i.e. the stereotactic frame) guarantees an optimal distribution of the dose computed by an original 3D volumetric algorithm. The robotic approach of the treatment stage has consisted to design a computer driven chair-framework cluster to position the target volume at the radiation unit isocenter.

Skeletal sequelae of radiation therapy for malignant childhood tumors

SciTech Connect

Butler, M.S.; Robertson, W.W. Jr.; Rate, W.

1990-02-01

One hundred forty-three patients who received radiation therapy for childhood tumors, and survived to the age of skeletal maturity, were studied by retrospective review of oncology records and roentgenograms. Diagnoses for the patients were the following: Hodgkin's lymphoma (44), Wilms's tumor (30), acute lymphocytic leukemia (26), non-Hodgkin's lymphoma (18), Ewing's sarcoma (nine), rhabdomyosarcoma (six), neuroblastoma (six), and others (four). Age at the follow-up examination averaged 18 years (range, 14-28 years). Average length of follow-up study was 9.9 years (range, two to 18 years). Asymmetry of the chest and ribs was seen in 51 (36%) of these children. Fifty (35%) hadmore » scoliosis; 14 had kyphosis. In two children, the scoliosis was treated with a brace, while one developed significant kyphosing scoliosis after laminectomy and had spinal fusion. Twenty-three (16%) patients complained of significant pain at the radiation sites. Twelve of the patients developed leg-length inequality; eight of those were symptomatic. Three patients developed second primary tumors. Currently, the incidence of significant skeletal sequelae is lower and the manifestations are less severe than reported in the years from 1940 to 1970. The reduction in skeletal complications may be attributed to shielding of growth centers, symmetric field selection, decreased total radiation doses, and sequence changes in chemotherapy.« less

Adjuvant and Salvage Radiation Therapy After Prostatectomy: American Society for Radiation Oncology/American Urological Association Guidelines

SciTech Connect

Valicenti, Richard K., E-mail: Richard.valicenti@ucdmc.ucdavis.edu; Thompson, Ian; Albertsen, Peter

Purpose: The purpose of this guideline was to provide a clinical framework for the use of radiation therapy after radical prostatectomy as adjuvant or salvage therapy. Methods and Materials: A systematic literature review using PubMed, Embase, and Cochrane database was conducted to identify peer-reviewed publications relevant to the use of radiation therapy after prostatectomy. The review yielded 294 articles; these publications were used to create the evidence-based guideline statements. Additional guidance is provided as Clinical Principles when insufficient evidence existed. Results: Guideline statements are provided for patient counseling, use of radiation therapy in the adjuvant and salvage contexts, defining biochemicalmore » recurrence, and conducting a restaging evaluation. Conclusions: Physicians should offer adjuvant radiation therapy to patients with adverse pathologic findings at prostatectomy (ie, seminal vesicle invastion, positive surgical margins, extraprostatic extension) and salvage radiation therapy to patients with prostate-specific antigen (PSA) or local recurrence after prostatectomy in whom there is no evidence of distant metastatic disease. The offer of radiation therapy should be made in the context of a thoughtful discussion of possible short- and long-term side effects of radiation therapy as well as the potential benefits of preventing recurrence. The decision to administer radiation therapy should be made by the patient and the multidisciplinary treatment team with full consideration of the patient's history, values, preferences, quality of life, and functional status. The American Society for Radiation Oncology and American Urological Association websites show this guideline in its entirety, including the full literature review.« less

Advances in prevention of radiation damage to visceral and solid organs in patients requiring radiation therapy of the trunk.

PubMed

Ritter, E F; Lee, C G; Tyler, D; Ferraro, F; Whiddon, C; Rudner, A M; Scully, S

1997-02-01

As a part of multimodality therapy, many patients with tumors of the trunk receive radiation therapy. The major morbidity of this therapy is often secondary to incidental radiation damage to tissues adjacent to treatment areas. We detail our use of saline breast implants placed in polyglycolic acid mesh sheets to displace visceral and solid organs away from the radiation field. Analysis of CT scans and dose volume histograms reveal that this technique successfully displaces uninvolved organs away from the radiation fields, thereby minimizing the radiation dose to such organs and tissues. We believe this is a safe and efficacious method to prevent radiation damage to visceral and solid organs adjacent to trunk tumor sites.

Treatment of esophageal cancer with radiation therapy -a pan-Chinese survey of radiation oncologists.

PubMed

Zhang, Yun; Liu, Jing; Zhang, Wencheng; Deng, Weiye; Yue, Jinbo

2017-05-23

Lots of controversies were found about the treatment in relation to radiation therapy (RT) for esophageal squamous cell carcinoma (ESCC). We designed a questionnaire of these controversies to do a pan-Chinese survey of radiation oncologists (ROs). For operable ESCC, 53% ROs chose surgery plus postoperative chemoradiotherapy (CRT), while 40% chose preoperative CRT plus surgery. For target volume of postoperative RT, most ROs (92%) would delineate tumor bed plus involved lymph nodes region before surgery. For definitive RT, most ROs (81%) would give patients higher RT dose to 60-65Gy. For radiation target volume, most ROs would give patients prophylactic irradiation of the bilateral superclavicular-lymph nodes region for cervical ESCC (93%), and the left gastric lymph nodes region for lower thoracic ESCC (72%). For the treatment of mediastinal lymph nodes, 72% ROs preferred elective nodal irradiation, while 28% did the involved nodal irradiation. For concurrent chemotherapy regimen, PF (5-Fu + cisplatin) and TP (cisplatin + paclitaxel) were used widely (49% and 46%, respectively). During simulation, four-dimensional computer tomography (4D CT) was not widely used (48%), even for cervical or lower thoracic ESCC (52%). For daily RT delivery, only 66% ROs would perform imaging guidance RT daily. In summary, more controversies existed in the treatment of ESCC with RT in China, including treatment strategy, radiation dose and target contour. Future goals include standardization of treatment strategy, radiation dose, and target contour, and application of 4D CT and daily imaging guidance, and pursuit of randomized trials in Chinese population.

Implementation of Remote 3-Dimensional Image Guided Radiation Therapy Quality Assurance for Radiation Therapy Oncology Group Clinical Trials

SciTech Connect

Cui Yunfeng; Galvin, James M.; Radiation Therapy Oncology Group, American College of Radiology, Philadelphia, Pennsylvania

2013-01-01

Purpose: To report the process and initial experience of remote credentialing of three-dimensional (3D) image guided radiation therapy (IGRT) as part of the quality assurance (QA) of submitted data for Radiation Therapy Oncology Group (RTOG) clinical trials; and to identify major issues resulting from this process and analyze the review results on patient positioning shifts. Methods and Materials: Image guided radiation therapy datasets including in-room positioning CT scans and daily shifts applied were submitted through the Image Guided Therapy QA Center from institutions for the IGRT credentialing process, as required by various RTOG trials. A centralized virtual environment is establishedmore » at the RTOG Core Laboratory, containing analysis tools and database infrastructure for remote review by the Physics Principal Investigators of each protocol. The appropriateness of IGRT technique and volumetric image registration accuracy were evaluated. Registration accuracy was verified by repeat registration with a third-party registration software system. With the accumulated review results, registration differences between those obtained by the Physics Principal Investigators and from the institutions were analyzed for different imaging sites, shift directions, and imaging modalities. Results: The remote review process was successfully carried out for 87 3D cases (out of 137 total cases, including 2-dimensional and 3D) during 2010. Frequent errors in submitted IGRT data and challenges in the review of image registration for some special cases were identified. Workarounds for these issues were developed. The average differences of registration results between reviewers and institutions ranged between 2 mm and 3 mm. Large discrepancies in the superior-inferior direction were found for megavoltage CT cases, owing to low spatial resolution in this direction for most megavoltage CT cases. Conclusion: This first experience indicated that remote review for 3D IGRT as

Pediatric chest and abdominopelvic CT: organ dose estimation based on 42 patient models.

PubMed

Tian, Xiaoyu; Li, Xiang; Segars, W Paul; Paulson, Erik K; Frush, Donald P; Samei, Ehsan

2014-02-01

To estimate organ dose from pediatric chest and abdominopelvic computed tomography (CT) examinations and evaluate the dependency of organ dose coefficients on patient size and CT scanner models. The institutional review board approved this HIPAA-compliant study and did not require informed patient consent. A validated Monte Carlo program was used to perform simulations in 42 pediatric patient models (age range, 0-16 years; weight range, 2-80 kg; 24 boys, 18 girls). Multidetector CT scanners were modeled on those from two commercial manufacturers (LightSpeed VCT, GE Healthcare, Waukesha, Wis; SOMATOM Definition Flash, Siemens Healthcare, Forchheim, Germany). Organ doses were estimated for each patient model for routine chest and abdominopelvic examinations and were normalized by volume CT dose index (CTDI(vol)). The relationships between CTDI(vol)-normalized organ dose coefficients and average patient diameters were evaluated across scanner models. For organs within the image coverage, CTDI(vol)-normalized organ dose coefficients largely showed a strong exponential relationship with the average patient diameter (R(2) > 0.9). The average percentage differences between the two scanner models were generally within 10%. For distributed organs and organs on the periphery of or outside the image coverage, the differences were generally larger (average, 3%-32%) mainly because of the effect of overranging. It is feasible to estimate patient-specific organ dose for a given examination with the knowledge of patient size and the CTDI(vol). These CTDI(vol)-normalized organ dose coefficients enable one to readily estimate patient-specific organ dose for pediatric patients in clinical settings. This dose information, and, as appropriate, attendant risk estimations, can provide more substantive information for the individual patient for both clinical and research applications and can yield more expansive information on dose profiles across patient populations within a practice. �

Pediatric Chest and Abdominopelvic CT: Organ Dose Estimation Based on 42 Patient Models

PubMed Central

Tian, Xiaoyu; Li, Xiang; Segars, W. Paul; Paulson, Erik K.; Frush, Donald P.

2014-01-01

Purpose To estimate organ dose from pediatric chest and abdominopelvic computed tomography (CT) examinations and evaluate the dependency of organ dose coefficients on patient size and CT scanner models. Materials and Methods The institutional review board approved this HIPAA–compliant study and did not require informed patient consent. A validated Monte Carlo program was used to perform simulations in 42 pediatric patient models (age range, 0–16 years; weight range, 2–80 kg; 24 boys, 18 girls). Multidetector CT scanners were modeled on those from two commercial manufacturers (LightSpeed VCT, GE Healthcare, Waukesha, Wis; SOMATOM Definition Flash, Siemens Healthcare, Forchheim, Germany). Organ doses were estimated for each patient model for routine chest and abdominopelvic examinations and were normalized by volume CT dose index (CTDIvol). The relationships between CTDIvol-normalized organ dose coefficients and average patient diameters were evaluated across scanner models. Results For organs within the image coverage, CTDIvol-normalized organ dose coefficients largely showed a strong exponential relationship with the average patient diameter (R2 > 0.9). The average percentage differences between the two scanner models were generally within 10%. For distributed organs and organs on the periphery of or outside the image coverage, the differences were generally larger (average, 3%–32%) mainly because of the effect of overranging. Conclusion It is feasible to estimate patient-specific organ dose for a given examination with the knowledge of patient size and the CTDIvol. These CTDIvol-normalized organ dose coefficients enable one to readily estimate patient-specific organ dose for pediatric patients in clinical settings. This dose information, and, as appropriate, attendant risk estimations, can provide more substantive information for the individual patient for both clinical and research applications and can yield more expansive information on dose profiles

Correlation of abdominopelvic computed tomography with clinical manifestations in methamphetamine body stuffers.

PubMed

Bahrami-Motlagh, Hooman; Hassanian-Moghaddam, Hossein; Zamini, Hedieh; Zamani, Nasim; Gachkar, Latif

2018-02-01

Little is known about methamphetamine body stuffers and correlation of clinical manifestations with imaging studies. Current study was done to determine abdominopelvic computed tomography findings and clinical manifestations in methamphetamine body stuffers. In an IRB-approved routine data base study, demographic characteristics, clinical findings, and CT results of 70 methamphetamine body stuffers were retrieved. According to the clinical manifestations, the patients were categorized into either benign- or severe-outcome group. Also, they were determined to have positive or negative CT results. In the group with positive results, number and place of the baggies were determined, as well. Results of the CT were compared between the two groups. Almost 43% of the patients had positive abdominopelvic CT results. Mean density of the packs was 176.2 ± 152.7 Hounsfield unit. Based on the clinical grounds, 57% of the patients were in the benign- and 33% were in the severe-outcome group. In the benign group, 45% of the patients had positive CTs while in the severe-risk group, this was 40% (p > 0.05). Except variables defined as severe outcome (seizure, intubation, creatinine level, aspartate aminotransferase level, creatine phosphokinase and troponin level), agitation, on-arrival pulse rate, lactate dehydrogenase, bicarbonate, base excess, loss of consciousness and hospitalization period were correlating factors. But in regression analysis, we could not find a significant variable that prognosticate severe outcome. It seems that there is no relationship between the CT findings and clinical manifestations of the methamphetamine body stuffers. Severe outcomes may be observed even in the face of negative CTs.

Intraoperative radiation therapy using mobile electron linear accelerators: report of AAPM Radiation Therapy Committee Task Group No. 72.

PubMed

Beddar, A Sam; Biggs, Peter J; Chang, Sha; Ezzell, Gary A; Faddegon, Bruce A; Hensley, Frank W; Mills, Michael D

2006-05-01

Intraoperative radiation therapy (IORT) has been customarily performed either in a shielded operating suite located in the operating room (OR) or in a shielded treatment room located within the Department of Radiation Oncology. In both cases, this cancer treatment modality uses stationary linear accelerators. With the development of new technology, mobile linear accelerators have recently become available for IORT. Mobility offers flexibility in treatment location and is leading to a renewed interest in IORT. These mobile accelerator units, which can be transported any day of use to almost any location within a hospital setting, are assembled in a nondedicated environment and used to deliver IORT. Numerous aspects of the design of these new units differ from that of conventional linear accelerators. The scope of this Task Group (TG-72) will focus on items that particularly apply to mobile IORT electron systems. More specifically, the charges to this Task Group are to (i) identify the key differences between stationary and mobile electron linear accelerators used for IORT, (ii) describe and recommend the implementation of an IORT program within the OR environment, (iii) present and discuss radiation protection issues and consequences of working within a nondedicated radiotherapy environment, (iv) describe and recommend the acceptance and machine commissioning of items that are specific to mobile electron linear accelerators, and (v) design and recommend an efficient quality assurance program for mobile systems.

Automatic CT simulation optimization for radiation therapy: A general strategy.

PubMed

Li, Hua; Yu, Lifeng; Anastasio, Mark A; Chen, Hsin-Chen; Tan, Jun; Gay, Hiram; Michalski, Jeff M; Low, Daniel A; Mutic, Sasa

2014-03-01

In radiation therapy, x-ray computed tomography (CT) simulation protocol specifications should be driven by the treatment planning requirements in lieu of duplicating diagnostic CT screening protocols. The purpose of this study was to develop a general strategy that allows for automatically, prospectively, and objectively determining the optimal patient-specific CT simulation protocols based on radiation-therapy goals, namely, maintenance of contouring quality and integrity while minimizing patient CT simulation dose. The authors proposed a general prediction strategy that provides automatic optimal CT simulation protocol selection as a function of patient size and treatment planning task. The optimal protocol is the one that delivers the minimum dose required to provide a CT simulation scan that yields accurate contours. Accurate treatment plans depend on accurate contours in order to conform the dose to actual tumor and normal organ positions. An image quality index, defined to characterize how simulation scan quality affects contour delineation, was developed and used to benchmark the contouring accuracy and treatment plan quality within the predication strategy. A clinical workflow was developed to select the optimal CT simulation protocols incorporating patient size, target delineation, and radiation dose efficiency. An experimental study using an anthropomorphic pelvis phantom with added-bolus layers was used to demonstrate how the proposed prediction strategy could be implemented and how the optimal CT simulation protocols could be selected for prostate cancer patients based on patient size and treatment planning task. Clinical IMRT prostate treatment plans for seven CT scans with varied image quality indices were separately optimized and compared to verify the trace of target and organ dosimetry coverage. Based on the phantom study, the optimal image quality index for accurate manual prostate contouring was 4.4. The optimal tube potentials for patient sizes

Modular design of H - synchrotrons for radiation therapy

NASA Astrophysics Data System (ADS)

Martin, R. L.

1989-04-01

A modular synchrotron for accelerating H - ions and a proton beam delivery system are being developed for radiation therapy with protons under SBIR grants from the National Cancer Institute. The advantage proposed for accelerating H - ions and utilizing charge exchange as a slow extraction mechanism lies in enhanced control of the extracted beam current, important for beam delivery with raster scanning for 3D dose contouring of a tumor site. Under these grants prototype magnets and vacuum systems are being constructed, appropriate H - sources are being developed and beam experiments will be carried out to demonstrate some of the key issues of this concept. The status of this program is described along with a discussion of a relatively inexpensive beam delivery system and a proposed program for its development.

Nanoparticles for Radiation Therapy Enhancement: the Key Parameters

PubMed Central

Retif, Paul; Pinel, Sophie; Toussaint, Magali; Frochot, Céline; Chouikrat, Rima; Bastogne, Thierry; Barberi-Heyob, Muriel

2015-01-01

This review focuses on the radiosensitization strategies that use high-Z nanoparticles. It does not establish an exhaustive list of the works in this field but rather propose constructive criticisms pointing out critical factors that could improve the nano-radiation therapy. Whereas most reviews show the chemists and/or biologists points of view, the present analysis is also seen through the prism of the medical physicist. In particular, we described and evaluated the influence of X-rays energy spectra using a numerical analysis. We observed a lack of standardization in preclinical studies that could partially explain the low number of translation to clinical applications for this innovative therapeutic strategy. Pointing out the critical parameters of high-Z nanoparticles radiosensitization, this review is expected to contribute to a larger preclinical and clinical development. PMID:26155318

X-ray energy optimization in minibeam radiation therapy.

PubMed

Prezado, Y; Thengumpallil, S; Renier, M; Bravin, A

2009-11-01

The purpose of this work is to assess which energy in minibeam radiation therapy provides the best compromise between the deposited dose in the tumor and the sparing of the healthy tissues. Monte Carlo simulations (PENELOPE 2006) have been used as a method to calculate the ratio of the peak-to-valley doses (PVDR) in the healthy tissues and in the tumor for different beam energies. The maximization of the ratio of PVDR in the healthy tissues and in the tumor has been used as a criterion. The main result of this work is that, for the parameters being used in preclinical trials (minibeam sizes of 600 microm and 1200 microm center-to-center separation), the optimum beam energy is 375 keV. The conclusion is that this is the energy of minibeams that should be used in the preclinical studies.

ROENTGEN: case-based reasoning and radiation therapy planning.

PubMed Central

Berger, J.

1992-01-01

ROENTGEN is a design assistant for radiation therapy planning which uses case-based reasoning, an artificial intelligence technique. It learns both from specific problem-solving experiences and from direct instruction from the user. The first sort of learning is the normal case-based method of storing problem solutions so that they can be reused. The second sort is necessary because ROENTGEN does not, initially, have an internal model of the physics of its problem domain. This dependence on explicit user instruction brings to the forefront representational questions regarding indexing, failure definition, failure explanation and repair. This paper presents the techniques used by ROENTGEN in its knowledge acquisition and design activities. PMID:1482869

Nanoparticles for Radiation Therapy Enhancement: the Key Parameters.

PubMed

Retif, Paul; Pinel, Sophie; Toussaint, Magali; Frochot, Céline; Chouikrat, Rima; Bastogne, Thierry; Barberi-Heyob, Muriel

2015-01-01

This review focuses on the radiosensitization strategies that use high-Z nanoparticles. It does not establish an exhaustive list of the works in this field but rather propose constructive criticisms pointing out critical factors that could improve the nano-radiation therapy. Whereas most reviews show the chemists and/or biologists points of view, the present analysis is also seen through the prism of the medical physicist. In particular, we described and evaluated the influence of X-rays energy spectra using a numerical analysis. We observed a lack of standardization in preclinical studies that could partially explain the low number of translation to clinical applications for this innovative therapeutic strategy. Pointing out the critical parameters of high-Z nanoparticles radiosensitization, this review is expected to contribute to a larger preclinical and clinical development.

Pelvic radiation therapy for gynecologic malignancy in geriatric patients

SciTech Connect

Grant, P.T.; Jeffrey, J.F.; Fraser, R.C.

Thirty-one patients, aged 75 years or older, who received pelvic radiation therapy as part of primary treatment for a gynecologic malignancy, were reviewed. Ten patients (32%) failed to complete their treatment and 4 patients (13%) died of treatment-related complications. The treatment-related complications were independent of increasing age, but did correlate closely with the patients' pretreatment ECOG performance status. Ten patients with performance levels of 2 or higher had a mortality rate of 30%, while 70% failed to complete treatment. Treatment fractions of greater than 220 cGy per day also resulted in unacceptably high complication rates. Alternative treatment formats should bemore » considered in geriatric patients with poor initial performance levels.« less

Hyperbaric Oxygen Therapy in Treating Long-Term Gastrointestinal Adverse Effects Caused by Radiation Therapy in Patients With Pelvic Cancer

ClinicalTrials.gov

2011-07-14

Bladder Cancer; Cervical Cancer; Colorectal Cancer; Endometrial Cancer; Gastrointestinal Complications; Long-term Effects Secondary to Cancer Therapy in Adults; Ovarian Cancer; Prostate Cancer; Radiation Toxicity; Sarcoma; Testicular Germ Cell Tumor; Vaginal Cancer

Proton-minibeam radiation therapy: A proof of concept

SciTech Connect

Prezado, Y.; Fois, G. R.

2013-03-15

Purpose: This Monte Carlo simulation work aims at studying a new radiotherapy approach called proton-minibeam radiation therapy (pMBRT). The main objective of this proof of concept was the evaluation of the possible gain in tissue sparing, thanks to the spatial fractionation of the dose, which could be used to deposit higher and potentially curative doses in clinical cases where tissue tolerances are a limit for conventional methods. Methods: Monte Carlo simulations (GATE v.6) have been used as a method to calculate the ratio of the peak-to-valley doses (PVDR) for arrays of proton minibeams of 0.7 mm width and several center-to-centermore » distances, at different depths in a water phantom. The beam penumbras were also evaluated as an important parameter for tissue sparing, for example, in the treatment of non-cancer diseases like epilepsy. Two proton energies were considered in this study: a clinically relevant energy (105 MeV) and a very high energy (1 GeV), to benefit from a reduced lateral scattering. For the latter case, an interlaced geometry was also evaluated. Results: Higher or similar PVDR than the ones obtained in x-rays minibeam radiation therapy were achieved in several pMBRT configurations. In addition, for the two energies studied, the beam penumbras are smaller than in the case of Gamma Knife radiosurgery. Conclusions: The high PVDR obtained for some configurations and the small penumbras in comparison with existing radiosurgery techniques, suggest a potential gain in healthy tissue sparing in this new technique. Biological studies are warranted to assess the effects of pMBRT on both normal and tumoral tissues.« less

Dosimetrically Triggered Adaptive Intensity Modulated Radiation Therapy for Cervical Cancer

SciTech Connect

Lim, Karen; Stewart, James; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario

2014-09-01

Purpose: The widespread use of intensity modulated radiation therapy (IMRT) for cervical cancer has been limited by internal target and normal tissue motion. Such motion increases the risk of underdosing the target, especially as planning margins are reduced in an effort to reduce toxicity. This study explored 2 adaptive strategies to mitigate this risk and proposes a new, automated method that minimizes replanning workload. Methods and Materials: Thirty patients with cervical cancer participated in a prospective clinical study and underwent pretreatment and weekly magnetic resonance (MR) scans over a 5-week course of daily external beam radiation therapy. Target volumes andmore » organs at risk (OARs) were contoured on each of the scans. Deformable image registration was used to model the accumulated dose (the real dose delivered to the target and OARs) for 2 adaptive replanning scenarios that assumed a very small PTV margin of only 3 mm to account for setup and internal interfractional motion: (1) a preprogrammed, anatomy-driven midtreatment replan (A-IMRT); and (2) a dosimetry-triggered replan driven by target dose accumulation over time (D-IMRT). Results: Across all 30 patients, clinically relevant target dose thresholds failed for 8 patients (27%) if 3-mm margins were used without replanning. A-IMRT failed in only 3 patients and also yielded an additional small reduction in OAR doses at the cost of 30 replans. D-IMRT assured adequate target coverage in all patients, with only 23 replans in 16 patients. Conclusions: A novel, dosimetry-triggered adaptive IMRT strategy for patients with cervical cancer can minimize the risk of target underdosing in the setting of very small margins and substantial interfractional motion while minimizing programmatic workload and cost.« less

Salvage radiation therapy and chemoradiation therapy for postoperative locoregional recurrence of esophageal cancer.

PubMed

Kobayashi, R; Yamashita, H; Okuma, K; Shiraishi, K; Ohtomo, K; Nakagawa, K

2014-01-01

The purpose of this retrospective study was to assess the efficacy of salvage radiation therapy (RT) or chemoradiation therapy (CRT) for locoregional recurrence (LR) of esophageal cancer after curative surgery. Forty-two patients who received salvage RT or CRT for LR of esophageal cancer after curative surgery between November 2000 and May 2012 were reviewed. The intended RT regimen was 60 Gy in 30 fractions combined with concurrent platinum-based chemotherapy. Median follow-up periods were 17.9 months for all evaluable patients and 28.2 months for patients still alive (19 patients) at analysis time. The 1-, 2-, and 3-year survival rates were 81.2 ± 6.4%, 51.3 ± 8.6%, and 41.1 ± 8.7%, respectively, with a median survival time of 24.3 ± 4.1 months. Out of 41 evaluable patients, 16 patients (39%) were alive beyond 2 years from salvage therapy. However, univariate analyses for overall survival showed no significant prognostic factor. Grade 3 or higher leukocytopenia was observed in 46% of the patients. Salvage RT or CRT for LR after surgery for esophageal cancer was safe and effective. These therapies may offer long-term survival to some patients. RT or CRT should be considered for LR. © 2013 Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

Investigation of Radiation Protection Methodologies for Radiation Therapy Shielding Using Monte Carlo Simulation and Measurement

NASA Astrophysics Data System (ADS)

Tanny, Sean

The advent of high-energy linear accelerators for dedicated medical use in the 1950's by Henry Kaplan and the Stanford University physics department began a revolution in radiation oncology. Today, linear accelerators are the standard of care for modern radiation therapy and can generate high-energy beams that can produce tens of Gy per minute at isocenter. This creates a need for a large amount of shielding material to properly protect members of the public and hospital staff. Standardized vault designs and guidance on shielding properties of various materials are provided by the National Council on Radiation Protection (NCRP) Report 151. However, physicists are seeking ways to minimize the footprint and volume of shielding material needed which leads to the use of non-standard vault configurations and less-studied materials, such as high-density concrete. The University of Toledo Dana Cancer Center has utilized both of these methods to minimize the cost and spatial footprint of the requisite radiation shielding. To ensure a safe work environment, computer simulations were performed to verify the attenuation properties and shielding workloads produced by a variety of situations where standard recommendations and guidance documents were insufficient. This project studies two areas of concern that are not addressed by NCRP 151, the radiation shielding workload for the vault door with a non-standard design, and the attenuation properties of high-density concrete for both photon and neutron radiation. Simulations have been performed using a Monte-Carlo code produced by the Los Alamos National Lab (LANL), Monte Carlo Neutrons, Photons 5 (MCNP5). Measurements have been performed using a shielding test port designed into the maze of the Varian Edge treatment vault.

Cancer stem cells, cancer cell plasticity and radiation therapy.

PubMed

Vlashi, Erina; Pajonk, Frank

2015-04-01

Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Intranasal melanoma treated with radiation therapy in three dogs.

PubMed

Davies, Owen; Spencer, Sarah; Necova, Slavomira; Holmes, Emma; Taylor, Angela; Blackwood, Laura; Lara-Garcia, Ana

2017-12-01

Three dogs were investigated for chronic unilateral nasal discharge. In all cases CT imaging showed an intranasal mass causing turbinate lysis and no evidence of metastasis. Cytology in cases 1 (a 14-year-old neutered male crossbreed dog) and 2 (a five-year-old neutered male German Shepherd dog) demonstrated a pleomorphic cell population with variable intracellular pigment suspicious of melanocytic neoplasia. Histopathology with immunohistochemistry (Melan-A and vimentin, plus PNL-2 in one case) confirmed the diagnosis of melanoma in all dogs. All dogs were treated with megavoltage radiotherapy using linear accelerators. Cases 1 and 3 (a nine-year-old neutered female beagle dog) received a hypofractionated (4 × 8 Gy) protocol and case 2 received a definitive (12 × 4 Gy) protocol. Complete remission was demonstrated on repeat CT scan five months after diagnosis in case 1 and seven months in case 2. Stable disease was documented on CT at four months for case 3; however, clinical signs in this dog remained controlled for 10 months in total. Case 1 died of unrelated causes five months after diagnosis, case 2 was euthanased due to the development of seizures 13 months after diagnosis, and case 3 was lost to follow-up 12 months after diagnosis. Melanoma should be considered as a rare differential diagnosis for primary nasal neoplasia in the dog and radiation therapy can be used as effective local therapy.

Radiation-induced lymphocyte apoptosis to predict radiation therapy late toxicity in prostate cancer patients.

PubMed

Schnarr, Kara; Boreham, Douglas; Sathya, Jinka; Julian, Jim; Dayes, Ian S

2009-08-01

To examine a potential correlation between the in vitro apoptotic response of lymphocytes to radiation and the risk of developing late gastrointestinal (GI)/genitourinary (GU) toxicity from radiotherapy for prostate cancer. Prostate cancer patients formerly enrolled in a randomized study were tested for radiosensitivity by using a radiation-induced lymphocyte apoptosis assay. Apoptosis was measured using flow cytometry-based Annexin-FITC/7AAD and DiOC(6)/7AAD assays in subpopulations of lymphocytes (total lymphocytes, CD4+, CD8+ and CD4-/CD8-) after exposure to an in vitro dose of 0, 2, 4, or 8 Gy. Patients with late toxicity after radiotherapy showed lower lymphocyte apoptotic responses to 8 Gy than patients who had not developed late toxicity (p = 0.01). All patients with late toxicity had apoptosis levels that were at or below the group mean. The negative predictive value in both apoptosis assays ranged from 95% to 100%, with sensitivity values of 83% to 100%. Apoptosis at lower dose points and in lymphocyte subpopulations had a weaker correlation with the occurrence of late toxicity. Lymphocyte apoptosis after 8 Gy of radiation has the potential to predict which patients will be spared late toxicity after radiation therapy. Further research should be performed to identify the specific subset of lymphocytes that correlates with late toxicity, followed by a corresponding prospective study.

Modern radiation therapy for primary cutaneous lymphomas: field and dose guidelines from the International Lymphoma Radiation Oncology Group.

PubMed

Specht, Lena; Dabaja, Bouthaina; Illidge, Tim; Wilson, Lynn D; Hoppe, Richard T

2015-05-01

Primary cutaneous lymphomas are a heterogeneous group of diseases. They often remain localized, and they generally have a more indolent course and a better prognosis than lymphomas in other locations. They are highly radiosensitive, and radiation therapy is an important part of the treatment, either as the sole treatment or as part of a multimodality approach. Radiation therapy of primary cutaneous lymphomas requires the use of special techniques that form the focus of these guidelines. The International Lymphoma Radiation Oncology Group has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the International Lymphoma Radiation Oncology Group steering committee on the use of radiation therapy in primary cutaneous lymphomas in the modern era. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

[Benchmark experiment to verify radiation transport calculations for dosimetry in radiation therapy].

PubMed

Renner, Franziska

2016-09-01

Monte Carlo simulations are regarded as the most accurate method of solving complex problems in the field of dosimetry and radiation transport. In (external) radiation therapy they are increasingly used for the calculation of dose distributions during treatment planning. In comparison to other algorithms for the calculation of dose distributions, Monte Carlo methods have the capability of improving the accuracy of dose calculations - especially under complex circumstances (e.g. consideration of inhomogeneities). However, there is a lack of knowledge of how accurate the results of Monte Carlo calculations are on an absolute basis. A practical verification of the calculations can be performed by direct comparison with the results of a benchmark experiment. This work presents such a benchmark experiment and compares its results (with detailed consideration of measurement uncertainty) with the results of Monte Carlo calculations using the well-established Monte Carlo code EGSnrc. The experiment was designed to have parallels to external beam radiation therapy with respect to the type and energy of the radiation, the materials used and the kind of dose measurement. Because the properties of the beam have to be well known in order to compare the results of the experiment and the simulation on an absolute basis, the benchmark experiment was performed using the research electron accelerator of the Physikalisch-Technische Bundesanstalt (PTB), whose beam was accurately characterized in advance. The benchmark experiment and the corresponding Monte Carlo simulations were carried out for two different types of ionization chambers and the results were compared. Considering the uncertainty, which is about 0.7 % for the experimental values and about 1.0 % for the Monte Carlo simulation, the results of the simulation and the experiment coincide. Copyright © 2015. Published by Elsevier GmbH.

Stroke After Radiation Therapy for Head and Neck Cancer: What Is the Risk?

SciTech Connect

Arthurs, Erin; Hanna, Timothy P.; Department of Oncology, Queen's University, Kingston, Ontario

Purpose: A retrospective population-based cohort study was conducted to determine the risk of ischemic stroke with respect to time, associated with curative radiation therapy in head and neck squamous cell carcinomas (HNSCC). Methods and Materials: On the basis of data from the Ontario Cancer Registry and regional cancer treatment centers, 14,069 patients were identified with diagnoses of squamous cell carcinoma of the oral cavity, larynx, and pharynx who were treated for cure between 1990 and 2010. Hazards of stroke and time to stroke were examined, accounting for the competing risk of death. Stroke risk factors identified through diagnostic and proceduralmore » administrative codes were adjusted for in the comparison between treatment regimens, which included surgery alone versus radiation therapy alone and surgery alone versus any exposure to radiation therapy. Results: Overall, 6% of patients experienced an ischemic stroke after treatment, with 5% experiencing a stroke after surgery, 8% after radiation therapy alone, and 6% after any exposure to radiation therapy. The cause-specific hazard ratios of ischemic stroke after radiation therapy alone and after any exposure to radiation therapy compared with surgery were 1.70 (95% confidence interval [CI]: 1.41-2.05) and 1.46 (95% CI: 1.23-1.73), respectively, after adjustment for stroke risk factors, patient factors, and disease-related factors. Conclusions: Radiation therapy was associated with an increased risk of ischemic stroke compared with surgery alone: for both radiation therapy alone and after all treatment modalities that included any radiation treatment were combined. Because of a shift toward a younger HNSCC patient population, our results speak to the need for adequate follow-up and survivorship care among patients who have been treated with radiation therapy. Advances in treatment that minimize chronic morbidity also require further evaluation.« less

Radiation Hardness of dSiPM Sensors in a Proton Therapy Radiation Environment

NASA Astrophysics Data System (ADS)

Diblen, Faruk; Buitenhuis, Tom; Solf, Torsten; Rodrigues, Pedro; van der Graaf, Emiel; van Goethem, Marc-Jan; Brandenburg, Sytze; Dendooven, Peter

2017-07-01

In vivo verification of dose delivery in proton therapy by means of positron emission tomography (PET) or prompt gamma imaging is mostly based on fast scintillation detectors. The digital silicon photomultiplier (dSiPM) allows excellent scintillation detector timing properties and is thus being considered for such verification methods. We present here the results of the first investigation of radiation damage to dSiPM sensors in a proton therapy radiation environment. Radiation hardness experiments were performed at the AGOR cyclotron facility at the KVI-Center for Advanced Radiation Technology, University of Groningen. A 150-MeV proton beam was fully stopped in a water target. In the first experiment, bare dSiPM sensors were placed at 25 cm from the Bragg peak, perpendicular to the beam direction, a geometry typical for an in situ implementation of a PET or prompt gamma imaging device. In the second experiment, dSiPM-based PET detectors containing lutetium yttrium orthosilicate scintillator crystal arrays were placed at 2 and 4 m from the Bragg peak, perpendicular to the beam direction; resembling an in-room PET implementation. Furthermore, the experimental setup was simulated with a Geant4-based Monte Carlo code in order to determine the angular and energy distributions of the neutrons and to determine the 1-MeV equivalent neutron fluences delivered to the dSiPM sensors. A noticeable increase in dark count rate (DCR) after an irradiation with about 108 1-MeV equivalent neutrons/cm2 agrees with observations by others for analog SiPMs, indicating that the radiation damage occurs in the single photon avalanche diodes and not in the electronics integrated on the sensor chip. It was found that in the in situ location, the DCR becomes too large for successful operation after the equivalent of a few weeks of use in a proton therapy treatment room (about 5 × 1013 protons). For PET detectors in an in-room setup, detector performance was unchanged even after an

MR-guided radiation therapy: transformative technology and its role in the central nervous system

PubMed Central

Tseng, Chia-Lin; Balter, James M.; Teng, Feifei; Parmar, Hemant A.; Sahgal, Arjun

2017-01-01

Abstract This review article describes advancement of magnetic resonance imaging technologies in radiation therapy planning, guidance, and adaptation of brain tumors. The potential for MR-guided radiation therapy to improve outcomes and the challenges in its adoption are discussed. PMID:28380637

21 CFR 892.5900 - X-ray radiation therapy system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

21 CFR 892.5900 - X-ray radiation therapy system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

21 CFR 892.5900 - X-ray radiation therapy system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

21 CFR 892.5900 - X-ray radiation therapy system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

21 CFR 892.5900 - X-ray radiation therapy system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

Calcified basal ganglionic mass 12 years after radiation therapy for medulloblastoma

SciTech Connect

Lichtor, T.; Wollmann, R.L.; Brown, F.D.

1984-04-01

A patient treated 12 years previously with an operation and radiation therapy for a medulloblastoma developed weakness of the left hand and perivascular calcification involving the right internal capsule and caudate nucleus. These findings are considered possible long-term complications of the radiation therapy.

21 CFR 892.5710 - Radiation therapy beam-shaping block.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy beam-shaping block. 892.5710 Section 892.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy beam-shaping...

Cord blood-derived cytokine-induced killer cellular therapy plus radiation therapy for esophageal cancer: a case report.

PubMed

Wang, Liming; Huang, Shigao; Dang, Yazheng; Li, Ming; Bai, Wen; Zhong, Zhanqiang; Zhao, Hongliang; Li, Yang; Liu, Yongjun; Wu, Mingyuan

2014-12-01

Esophageal cancer is a serious malignancy with regards to mortality and prognosis. Current treatment options include multimodality therapy mainstays of current treatment including surgery, radiation, and chemotherapy. Cell therapy for esophageal cancer is an advancing area of research. We report a case of esophageal cancer following cord blood-derived cytokine-induced killer cell infusion and adjuvant radiotherapy. Initially, she presented with poor spirit, full liquid diets, and upper abdominal pain. Through cell therapy plus adjuvant radiotherapy, the patient remitted and was self-reliant. Recognition of this curative effect of sequent therapy for esophageal cancer is important to enable appropriate treatment. This case highlights cord blood-derived cytokine-induced killer cell therapy significantly alleviates the adverse reaction of radiation and improves the curative effect. Cell therapy plus adjuvant radiotherapy can be a safe and effective treatment for esophageal cancer.

Cost-Effectiveness Analysis of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Anal Cancer

SciTech Connect

Hodges, Joseph C., E-mail: joseph.hodges@utsouthwestern.edu; Beg, Muhammad S.; Das, Prajnan

2014-07-15

Purpose: To compare the cost-effectiveness of intensity modulated radiation therapy (IMRT) and 3-dimensional conformal radiation therapy (3D-CRT) for anal cancer and determine disease, patient, and treatment parameters that influence the result. Methods and Materials: A Markov decision model was designed with the various disease states for the base case of a 65-year-old patient with anal cancer treated with either IMRT or 3D-CRT and concurrent chemotherapy. Health states accounting for rates of local failure, colostomy failure, treatment breaks, patient prognosis, acute and late toxicities, and the utility of toxicities were informed by existing literature and analyzed with deterministic and probabilistic sensitivitymore » analysis. Results: In the base case, mean costs and quality-adjusted life expectancy in years (QALY) for IMRT and 3D-CRT were $32,291 (4.81) and $28,444 (4.78), respectively, resulting in an incremental cost-effectiveness ratio of $128,233/QALY for IMRT compared with 3D-CRT. Probabilistic sensitivity analysis found that IMRT was cost-effective in 22%, 47%, and 65% of iterations at willingness-to-pay thresholds of $50,000, $100,000, and $150,000 per QALY, respectively. Conclusions: In our base model, IMRT was a cost-ineffective strategy despite the reduced acute treatment toxicities and their associated costs of management. The model outcome was sensitive to variations in local and colostomy failure rates, as well as patient-reported utilities relating to acute toxicities.« less

Quality of Intensity Modulated Radiation Therapy Treatment Plans Using a {sup 60}Co Magnetic Resonance Image Guidance Radiation Therapy System

SciTech Connect

Wooten, H. Omar, E-mail: hwooten@radonc.wustl.edu; Green, Olga; Yang, Min

2015-07-15

Purpose: This work describes a commercial treatment planning system, its technical features, and its capabilities for creating {sup 60}Co intensity modulated radiation therapy (IMRT) treatment plans for a magnetic resonance image guidance radiation therapy (MR-IGRT) system. Methods and Materials: The ViewRay treatment planning system (Oakwood Village, OH) was used to create {sup 60}Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup plans using a third-party linear accelerator (linac)-based planning system were also created. Plans were evaluated bymore » attending physicians and approved for treatment. The {sup 60}Co and linac plans were compared by evaluating conformity numbers (CN) with 100% and 95% of prescription reference doses and heterogeneity indices (HI) for planning target volumes (PTVs) and maximum, mean, and dose-volume histogram (DVH) values for OARs. Results: All {sup 60}Co IMRT plans achieved PTV coverage and OAR sparing that were similar to linac plans. PTV conformity for {sup 60}Co was within <1% and 3% of linac plans for 100% and 95% prescription reference isodoses, respectively, and heterogeneity was on average 4% greater. Comparisons of OAR mean dose showed generally better sparing with linac plans in the low-dose range <20 Gy, but comparable sparing for organs with mean doses >20 Gy. The mean doses for all {sup 60}Co plan OARs were within clinical tolerances. Conclusions: A commercial {sup 60}Co MR-IGRT device can produce highly conformal IMRT treatment plans similar in quality to linac IMRT for a variety of disease sites. Additional work is in progress to evaluate the clinical benefit of other novel features of this MR-IGRT system.« less

A Phase III Study of Conventional Radiation Therapy Plus Thalidomide Versus Conventional Radiation Therapy for Multiple Brain Metastases (RTOG 0118)

SciTech Connect

Knisely, Jonathan P.S.; Berkey, Brian; Chakravarti, Arnab

2008-05-01

Purpose: To compare whole-brain radiation therapy (WBRT) with WBRT combined with thalidomide for patients with brain metastases not amenable to resection or radiosurgery. Patients and Methods: Patients with Zubrod performance status 0-1, MRI-documented multiple (>3), large (>4 cm), or midbrain brain metastases arising from a histopathologically confirmed extracranial primary tumor, and an anticipated survival of >8 weeks were randomized to receive WBRT to a dose of 37.5 Gy in 15 fractions with or without thalidomide during and after WBRT. Prerandomization stratification used Radiation Therapy Oncology Group (RTOG) Recursive Partitioning Analysis (RPA) Class and whether post-WBRT chemotherapy was planned. Endpoints includedmore » overall survival, progression-free survival, time to neurocognitive progression, the cause of death, toxicities, and quality of life. A protocol-planned interim analysis documented that the trial had an extremely low probability of ever showing a significant difference favoring the thalidomide arm given the results at the time of the analysis, and it was therefore closed on the basis of predefined statistical guidelines. Results: Enrolled in the study were 332 patients. Of 183 accrued patients, 93 were randomized to receive WBRT alone and 90 to WBRT and thalidomide. Median survival was 3.9 months for both arms. No novel toxicities were seen, but thalidomide was not well tolerated in this population. Forty-eight percent of patients discontinued thalidomide because of side effects. Conclusion: Thalidomide provided no survival benefit for patients with multiple, large, or midbrain metastases when combined with WBRT; nearly half the patients discontinued thalidomide due to side effects.« less

Adaptive radiation therapy for postprostatectomy patients using real-time electromagnetic target motion tracking during external beam radiation therapy.

PubMed

Zhu, Mingyao; Bharat, Shyam; Michalski, Jeff M; Gay, Hiram A; Hou, Wei-Hsien; Parikh, Parag J

2013-03-15

Using real-time electromagnetic (EM) transponder tracking data recorded by the Calypso 4D Localization System, we report inter- and intrafractional target motion of the prostate bed, describe a strategy to evaluate treatment adequacy in postprostatectomy patients receiving intensity modulated radiation therapy (IMRT), and propose an adaptive workflow. Tracking data recorded by Calypso EM transponders was analyzed for postprostatectomy patients that underwent step-and-shoot IMRT. Rigid target motion parameters during beam delivery were calculated from recorded transponder positions in 16 patients with rigid transponder geometry. The delivered doses to the clinical target volume (CTV) were estimated from the planned dose matrix and the target motion for the first 3, 5, 10, and all fractions. Treatment adequacy was determined by comparing the delivered minimum dose (Dmin) with the planned Dmin to the CTV. Treatments were considered adequate if the delivered CTV Dmin is at least 95% of the planned CTV Dmin. Translational target motion was minimal for all 16 patients (mean: 0.02 cm; range: -0.12 cm to 0.07 cm). Rotational motion was patient-specific, and maximum pitch, yaw, and roll were 12.2, 4.1, and 10.5°, respectively. We observed inadequate treatments in 5 patients. In these treatments, we observed greater target rotations along with large distances between the CTV centroid and transponder centroid. The treatment adequacy from the initial 10 fractions successfully predicted the overall adequacy in 4 of 5 inadequate treatments and 10 of 11 adequate treatments. Target rotational motion could cause underdosage to partial volume of the postprostatectomy targets. Our adaptive treatment strategy is applicable to post-prostatectomy patients receiving IMRT to evaluate and improve radiation therapy delivery. Copyright © 2013 Elsevier Inc. All rights reserved.

Role of Definitive Radiation Therapy in Carcinoma of Unknown Primary in the Abdomen and Pelvis

SciTech Connect

Kelly, Patrick; Das, Prajnan; Varadhachary, Gauri R.

2012-04-01

Objectives: Carcinoma of unknown primary (CUP) in the abdomen and pelvis is a heterogeneous group of cancers with no standard treatment. Considered by many to be incurable, these patients are often treated with chemotherapy alone. In this study, we determined the effectiveness of radiation therapy in combination with chemotherapy in patients with CUP in the abdomen and pelvis. Patients and Methods: Medical records were reviewed for 37 patients with CUP treated with radiation therapy for disease located in the soft tissues and/or nodal basins of the abdomen and pelvis at University of Texas M.D. Anderson Cancer between 2002 and 2009.more » All patients underwent chemotherapy, either before or concurrent with radiation therapy. Patients were selected for radiation therapy on the basis of histologic type, disease extent, and prior therapy response. Twenty patients underwent definitive radiation therapy (defined as radiation therapy targeting all known disease sites with at least 45 Gy) and 17 patients underwent palliative radiation therapy. Only 6 patients had surgical resection of their disease. Patient and treatment characteristics were extracted and the endpoints of local disease control, progression-free survival (PFS), overall survival (OS), and treatment-related toxicity incidence were analyzed. Results: The 2-year PFS and OS rates for the entire cohort were 32% and 57%, respectively. However, in patients treated with definitive radiation therapy, the rates were 48% and 76%, and 7 patients lived more than 3 years after treatment with no evidence of disease progression. Nevertheless, radiation-associated toxicity was significant in this cohort, as 40% experienced Grade 2 or higher late toxicities. Conclusions: The use of definitive radiation therapy should be considered in selected patients with CUP in the soft tissues or nodal basins of the abdomen and pelvis.« less

Applications of Cherenkov Light Emission for Dosimetry in Radiation Therapy

NASA Astrophysics Data System (ADS)

Glaser, Adam Kenneth

Since its discovery in the 1930's, the Cherenkov effect has been paramount in the development of high-energy physics research. It results in light emission from charged particles traveling faster than the local speed of light in a dielectric medium. The ability of this emitted light to describe a charged particle's trajectory, energy, velocity, and mass has allowed scientists to study subatomic particles, detect neutrinos, and explore the properties of interstellar matter. However, only recently has the phenomenon been considered in the practical context of medical physics and radiation therapy dosimetry, where Cherenkov light is induced by clinical x-ray photon, electron, and proton beams. To investigate the relationship between this phenomenon and dose deposition, a Monte Carlo plug-in was developed within the Geant4 architecture for medically-oriented simulations (GAMOS) to simulate radiation-induced optical emission in biological media. Using this simulation framework, it was determined that Cherenkov light emission may be well suited for radiation dosimetry of clinically used x-ray photon beams. To advance this application, several novel techniques were implemented to realize the maximum potential of the signal, such as time-gating for maximizing the signal to noise ratio (SNR) and Cherenkov-excited fluorescence for generating isotropic light release in water. Proof of concept experiments were conducted in water tanks to demonstrate the feasibility of the proposed method for two-dimensional (2D) projection imaging, three-dimensional (3D) parallel beam tomography, large field of view 3D cone beam tomography, and video-rate dynamic imaging of treatment plans for a number of common radiotherapy applications. The proposed dosimetry method was found to have a number of unique advantages, including but not limited to its non-invasive nature, water-equivalence, speed, high-resolution, ability to provide full 3D data, and potential to yield data in-vivo. Based on

Ejaculation profiles of men following radiation therapy for prostate cancer.

PubMed

Sullivan, John F; Stember, Doron S; Deveci, Serkan; Akin-Olugbade, Yemi; Mulhall, John P

2013-05-01

Radical prostatectomy (RP) is associated with anejaculation, which for some men is a source of bother and sexual dissatisfaction. Clinical experience has shown us some men after pelvic radiation therapy (RT) also experience anejaculation. This analysis was conducted to define the ejaculation profiles of men after RT for prostate cancer (PCa). As a routine part of the sexual health evaluation for post-RT patients, men provided information regarding their ejaculatory function and orgasm. Analysis was conducted of a sexual medicine database reviewing demographic data, PCa factors, erectile, ejaculatory, and orgasmic function. Men with prior history of RP, cryotherapy, focal therapies, and androgen deprivation therapy (ADT) were excluded. Patients completed the International Index of Erectile Function (IIEF) questionnaire at follow-up visits commencing with the first posttreatment visit and specific attention was paid to the IIEF orgasm domain. Three hundred and sixty-four consecutive patients were included. Two hundred and fifty-two patients had external beam, and 112 patients had brachytherapy (BT). Mean age was 64 ± 11 (42-78) years and mean follow-up after RT was 6 ± 4.5 years. Mean prostate size at time of RT was 42 ± 21 g. Of the entire population, 72% lost the ability to ejaculate in an antegrade fashion after prostate RT by their last visit. The proportion experiencing anejaculation at 1, 3, and 5 years after RT was 16%, 69%, and 89%, respectively. For men with at least two IIEF questionnaires completed, the orgasm domain scores decreased dramatically over the follow-up period; orgasm domain scores (0-10): <12 months post-RT 7.4, 13-24 months 5.4, 25-36 months 3.2, >36 months 2.8 (P < 0.01). Multivariable analysis identified several factors predictive of failure to ejaculate: older age, ADT, RT dose > 100 Gy, and smaller prostates at the time of RT. The vast majority of men after prostate RT will experience anejaculation and should be

Benzydamine hydrochloride in prevention and management of pain in oral mucositis associated with radiation therapy

SciTech Connect

Epstein, J.B.; Stevenson-Moore, P.

1986-08-01

Benzydamine hydrochloride rinse reduced pain associated with radiation mucositis when it was used during the course of radiation therapy. Fewer patients using benzydamine rinse required systemic analgesics. All patients using benzydamine tolerated the rinse well and continued with regular rinsing throughout the course of radiation therapy. Benzydamine hydrochloride is currently undergoing clinical trials in the United States for application for approval from the Food and Drug Administration.

Cost-Effectiveness of Surgery, Stereotactic Body Radiation Therapy, and Systemic Therapy for Pulmonary Oligometastases

SciTech Connect

Lester-Coll, Nataniel H., E-mail: nataniel.lester-coll@yale.edu; Rutter, Charles E.; Bledsoe, Trevor J.

Introduction: Pulmonary oligometastases have conventionally been managed with surgery and/or systemic therapy. However, given concerns about the high cost of systemic therapy and improvements in local treatment of metastatic cancer, the optimal cost-effective management of these patients is unclear. Therefore, we sought to assess the cost-effectiveness of initial management strategies for pulmonary oligometastases. Methods and Materials: A cost-effectiveness analysis using a Markov modeling approach was used to compare average cumulative costs, quality adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) among 3 initial disease management strategies: video-assisted thoracic surgery (VATS) wedge resection, stereotactic body radiation therapy (SBRT), and systemicmore » therapy among 5 different cohorts of patient disease: (1) melanoma; (2) non-small cell lung cancer adenocarcinoma without an EGFR mutation (NSCLC AC); (3) NSCLC with an EGFR mutation (NSCLC EGFRm AC); (4) NSCLC squamous cell carcinoma (NSCLC SCC); and (5) colon cancer. One-way sensitivity analyses and probabilistic sensitivity analyses were performed to analyze uncertainty with regard to model parameters. Results: In the base case, SBRT was cost effective for melanoma, with costs/net QALYs of $467,787/0.85. In patients with NSCLC, the most cost-effective strategies were SBRT for AC ($156,725/0.80), paclitaxel/carboplatin for SCC ($123,799/0.48), and erlotinib for EGFRm AC ($147,091/1.90). Stereotactic body radiation therapy was marginally cost-effective for EGFRm AC compared to erlotinib with an incremental cost-effectiveness ratio of $126,303/QALY. For colon cancer, VATS wedge resection ($147,730/2.14) was the most cost-effective strategy. Variables with the greatest influence in the model were erlotinib-associated progression-free survival (EGFRm AC), toxicity (EGFRm AC), cost of SBRT (NSCLC SCC), and patient utilities (all histologies). Conclusions: Video

Retrospective study of orthovoltage radiation therapy for nasal tumors in 42 dogs.

PubMed

Northrup, N C; Etue, S M; Ruslander, D M; Rassnick, K M; Hutto, D L; Bengtson, A; Rand, W; Moore, A S

2001-01-01

Megavoltage radiation therapy currently is the standard of care for dogs with nasal tumors. Some studies report that surgery and adjunctive orthovoltage radiation therapy result in longer control of these tumors than does megavoltage radiation therapy alone. This study reports less effective control of nasal tumors in dogs treated with surgery and orthovoltage radiation than previously observed, supporting the superiority of megavoltage radiation therapy for these tumors. In addition, this study suggests 2 new prognostic indicators for dogs with nasal tumors and describes toxicity associated with surgery and orthovoltage therapy. Forty-two dogs with nasal tumors were treated with surgical cytoreduction and 48 Gy orthovoltage radiation therapy administered in twelve 4-Gy fractions. Median survival was 7.4 months. One- and 2-year survival rates were 37% and 17%, respectively. Dogs with facial deformity had shorter survival than those without deformity (P = .005). Dogs with resolution of clinical signs after treatment had longer survival than those with chronic nasal signs (P = .0001). Acute radiation toxicity was moderate to severe for skin and eye and negligible for oral mucosa. Toxicity healed within 1 month after radiation therapy. Late toxicity was mild, but 70% of evaluable dogs experienced persistent ocular signs. Only 39% of dogs achieved a disease-free period.

A comprehensive dosimetric study of pancreatic cancer treatment using three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), volumetric-modulated radiation therapy (VMAT), and passive-scattering and modulated-scanning proton therapy (PT)

SciTech Connect

Ding, Xuanfeng; Dionisi, Francesco; Tang, Shikui

With traditional photon therapy to treat large postoperative pancreatic target volume, it often leads to poor tolerance of the therapy delivered and may contribute to interrupted treatment course. This study was performed to evaluate the potential advantage of using passive-scattering (PS) and modulated-scanning (MS) proton therapy (PT) to reduce normal tissue exposure in postoperative pancreatic cancer treatment. A total of 11 patients with postoperative pancreatic cancer who had been previously treated with PS PT in University of Pennsylvania Roberts Proton Therapy Center from 2010 to 2013 were identified. The clinical target volume (CTV) includes the pancreatic tumor bed as wellmore » as the adjacent high-risk nodal areas. Internal (iCTV) was generated from 4-dimensional (4D) computed tomography (CT), taking into account target motion from breathing cycle. Three-field and 4-field 3D conformal radiation therapy (3DCRT), 5-field intensity-modulated radiation therapy, 2-arc volumetric-modulated radiation therapy, and 2-field PS and MS PT were created on the patients’ average CT. All the plans delivered 50.4 Gy to the planning target volume (PTV). Overall, 98% of PTV was covered by 95% of the prescription dose and 99% of iCTV received 98% prescription dose. The results show that all the proton plans offer significant lower doses to the left kidney (mean and V{sub 18} {sub Gy}), stomach (mean and V{sub 20} {sub Gy}), and cord (maximum dose) compared with all the photon plans, except 3-field 3DCRT in cord maximum dose. In addition, MS PT also provides lower doses to the right kidney (mean and V{sub 18} {sub Gy}), liver (mean dose), total bowel (V{sub 20} {sub Gy} and mean dose), and small bowel (V{sub 15} {sub Gy} absolute volume ratio) compared with all the photon plans and PS PT. The dosimetric advantage of PT points to the possibility of treating tumor bed and comprehensive nodal areas while providing a more tolerable treatment course that could be used for

Margin reduction from image guided radiation therapy for soft tissue sarcoma: Secondary analysis of Radiation Therapy Oncology Group 0630 results.

PubMed

Li, X Allen; Chen, Xiaojian; Zhang, Qiang; Kirsch, David G; Petersen, Ivy; DeLaney, Thomas F; Freeman, Carolyn R; Trotti, Andy; Hitchcock, Ying; Bedi, Meena; Haddock, Michael; Salerno, Kilian; Dundas, George; Wang, Dian

2016-01-01

Six imaging modalities were used in Radiation Therapy Oncology Group (RTOG) 0630, a study of image guided radiation therapy (IGRT) for primary soft tissue sarcomas of the extremity. We analyzed all daily patient-repositioning data collected in this trial to determine the impact of daily IGRT on clinical target volume-to-planning target volume (CTV-to-PTV) margin. Daily repositioning data, including shifts in right-left (RL), superior-inferior (SI), and anterior-posterior (AP) directions and rotations for 98 patients enrolled in RTOG 0630 from 18 institutions were analyzed. Patients were repositioned daily on the basis of bone anatomy by using pretreatment images, including kilovoltage orthogonal images (KVorth), megavoltage orthogonal images (MVorth), KV fan-beam computed tomography (KVCT), KV cone beam CT (KVCB), MV fan-beam CT (MVCT), and MV cone beam CT (MVCB). Means and standard deviations (SDs) for each shift and rotation were calculated for each patient and for each IGRT modality. The Student's t tests and F-tests were performed to analyze the differences in the means and SDs. Necessary CTV-to-PTV margins were estimated. The repositioning shifts and day-to-day variations were large and generally similar for the 6 imaging modalities. Of the 2 most commonly used modalities, MVCT and KVorth, there were no statistically significant differences in the shifts and rotations (P = .15 and .59 for the RL and SI shifts, respectively; and P = .22 for rotation), except for shifts in AP direction (P = .002). The estimated CTV-to-PTV margins in the RL, SI, and AP directions would be 13.0, 10.4, and 11.7 mm from MVCT data, respectively, and 13.1, 8.6, and 10.8 mm from KVorth data, respectively, indicating that margins substantially larger than 5 mm used with daily IGRT would be required in the absence of IGRT. The observed large daily repositioning errors and the large variations among institutions imply that daily IGRT is necessary for this tumor site, particularly in multi

Synergizing Radiation Therapy and Immunotherapy for Curing Incurable Cancers: Opportunities and Challenges

PubMed Central

Hodge, James W.; Guha, Chandan; Neefjes, Jacques; Gulley, James L.

2012-01-01

The combination of radiation therapy and immunotherapy holds particular promise as a strategy for cancer therapeutics. There is evidence that immunotherapy is most beneficial alone when employed early in the disease process or in combination with standard therapies (e.g., radiation) later in the disease process. Indeed, radiation may act synergistically with immunotherapy to enhance immune responses, inhibit immunosuppression, and/or alter the phenotype of tumor cells, thus rendering them more susceptible to immune-mediated killing. Furthermore, as monotherapies, both immunotherapy and radiation may be insufficient to eliminate tumor masses. However, following immunization with a cancer vaccine, the destruction of even a small percentage of tumor cells by radiation could result in cross-priming and presentation of tumor antigens to the immune system, thereby potentiating antitumor responses. Learning how to exploit radiation-induced changes to tumor-cell antigens, and how to induce effective immune responses to these cumulatively immunogenic stimuli, is an exciting frontier in cancer therapy research. This review examines a) mechanisms by which many forms of radiation therapy can induce or augment antitumor immune responses and b) preclinical systems that demonstrate that immunotherapy can be effectively combined with radiation therapy. Finally, we review current clinical trials where standard-of-care radiation therapy is being combined with immunotherapy. PMID:18777956

Theoretical dosimetric evaluation of carbon and oxygen minibeam radiation therapy.

PubMed

González, Wilfredo; Peucelle, Cécile; Prezado, Yolanda

2017-05-01

Charged particles have several advantages over x-ray radiations, both in terms of physics and radiobiology. The combination of these advantages with those of minibeam radiation therapy (MBRT) could help enhancing the therapeutic index for some cancers with poor prognosis. Among the different ions explored for therapy, carbon ions are considered to provide the optimum physical and biological characteristics. Oxygen could be advantageous due to a reduced oxygen enhancement ratio along with a still moderate biological entrance dose. The aforementioned reasons justified an in-depth evaluation of the dosimetric features of carbon and oxygen minibeam radiation therapy to establish the interest of further explorations of this avenue. The GATE/Geant4 6.2 Monte Carlo simulation platform was employed to simulate arrays of rectangular carbon and oxygen minibeams (600 μm × 2 cm) at a water phantom entrance. They were assumed to be generated by means of a magnetic focusing. The irradiations were performed with a 2-cm-long spread-out Bragg peak (SOBP) centered at 7-cm-depth. Several center-to-center (c-t-c) distances were considered. Peak and valley doses, as well as peak-to-valley dose ratio (PVDR) and the relative contribution of nuclear fragments and electromagnetic processes were assessed. In addition, the type and proportion of the secondary nuclear fragments were evaluated in both peak and valley regions. Carbon and oxygen MBRT lead to very similar dose distributions. No significant advantage of oxygen over carbon ions was observed from physical point of view. Favorable dosimetric features were observed for both ions. Thanks to the reduced lateral scattering, the standard shape of the depth dose curves (in the peaks) is maintained even for submillimetric beam sizes. When a narrow c-t-c is considered (910-980 μm), a (quasi) homogenization of the dose can be obtained at the target, while a spatial fractionation of the dose is maintained in the proximal normal tissues with

Radiation therapy for Bowen's disease of the skin

SciTech Connect

Lukas VanderSpek, Lauren A.; Pond, Gregory R.; Wells, Woodrow

2005-10-01

Purpose: To assess the clinical outcome in the radiation therapy (RT) of squamous carcinoma in situ of the skin (Bowen's disease). We focused on the local control rate and the toxicity according to the biologically effective dose (BED). Methods and Materials: A retrospective review was performed on 44 patients with Bowen's disease treated at Princess Margaret Hospital from April 1985 to November 2000. RT was the primary treatment for 32 patients, whereas 12 received RT for residual disease after local ablative therapy. Lesions were located as follows: scalp, 9 patients (20%); face, 12 (27%); trunk, 6 (14%), extremity, 12 (27%),more » perianal, 3 (7%), and penis, 2 (5%). Orthovoltage X-rays were used in the majority (39 of 44, 89%). There was no standard fractionation regimen: some physicians prescribed high doses, as for invasive skin cancer, whereas others prescribed lower doses because of the noninvasive nature of the disease, a sensitive anatomic location (e.g., extremity), or large treatment area. Because of the variations in fractionation regimens, BED was used as a common metric for biologic effect in the comparison of different regimens and analyzed for correlation with recurrence and toxicity. Local control was defined as the lack of persistent or recurrent disease at the treated site for the follow-up period. Grade 4 toxicity was defined as necrosis (cartilage/bone damage) and/or ulceration for a duration of >3 months. Results: The mean patient age was 67.7 years, and the male/female ratio was 29:15. The median pretreatment lesion size was 2.65 cm{sup 2} (range, 0.07-34.56 cm{sup 2}). Complete remission was achieved in 42 patients, with follow-up unavailable for the remaining 2 patients. Subsequently, 3 patients experienced recurrences at 0.2, 1.1, and 1-1.5 years after complete remission. One recurrence was Bowen's disease (local); the others were squamous cell carcinoma (one local, one marginal). Four patients experienced a new squamous lesion at a

Academic Career Selection and Retention in Radiation Oncology: The Joint Center for Radiation Therapy Experience

SciTech Connect

Balboni, Tracy A.; Chen, M.-H.; Harris, Jay R.

2007-05-01

Purpose: The United States healthcare system has witnessed declining reimbursement and increasing documentation requirements for longer than 10 years. These have decreased the time available to academic faculty for teaching and mentorship. The impact of these changes on the career choices of residents is unknown. The purpose of this report was to determine whether changes have occurred during the past decade in the proportion of radiation oncology trainees from a single institution entering and staying in academic medicine. Methods and Materials: We performed a review of the resident employment experience of Harvard Joint Center for Radiation Therapy residents graduating duringmore » 13 recent consecutive years (n = 48 residents). The outcomes analyzed were the initial selection of an academic vs. nonacademic career and career changes during the first 3 years after graduation. Results: Of the 48 residents, 65% pursued an academic career immediately after graduation, and 44% remained in academics at the last follow-up, after a median of 6 years. A later graduation year was associated with a decrease in the proportion of graduates immediately entering academic medicine (odds ratio, 0.78; 95% confidence interval, 0.65-0.94). However, the retention rate at 3 years of those who did immediately enter academics increased with a later graduation year (p = 0.03). Conclusion: During a period marked by notable changes in the academic healthcare environment, the proportion of graduating Harvard Joint Center for Radiation Therapy residents pursuing academic careers has been declining; however, despite this decline, the retention rates in academia have increased.« less

Interobserver variability of radiation therapists aligning to fiducial markers for prostate radiation therapy.

PubMed

Deegan, Timothy; Owen, Rebecca; Holt, Tanya; Roberts, Lisa; Biggs, Jennifer; McCarthy, Alicia; Parfitt, Matthew; Fielding, Andrew

2013-08-01

As the use of fiducial markers (FMs) for the localisation of the prostate during external beam radiation therapy (EBRT) has become part of routine practice, radiation therapists (RTs) have become increasingly responsible for online image interpretation. The aim of this investigation was to quantify the limits of agreement (LoA) between RTs when localising to FMs with orthogonal kilovoltage (kV) imaging. Six patients receiving prostate EBRT utilising FMs were included in this study. Treatment localisation was performed using kV imaging prior to each fraction. Online stereoscopic assessment of FMs, performed by the treating RTs, was compared with the offline assessment by three RTs. Observer agreement was determined by pairwise Bland-Altman analysis. Stereoscopic analysis of 225 image pairs was performed online at the time of treatment, and offline by three RT observers. Eighteen pairwise Bland-Altman analyses were completed to assess the level of agreement between observers. Localisation by RTs was found to be within clinically acceptable 95% LoAs. Small differences between RTs, in both the online and offline setting, were found to be within clinically acceptable limits. RTs were able to make consistent and reliable judgements when matching FMs on planar kV imaging. © 2013 The Authors. Journal of Medical Imaging and Radiation Oncology © 2013 The Royal Australian and New Zealand College of Radiologists.

Comparison of three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and volumetric-modulated arc therapy in the treatment of cervical esophageal carcinoma.

PubMed

Yang, Hao; Feng, Cong; Cai, Bo-Ning; Yang, Jun; Liu, Hai-Xia; Ma, Lin

2017-02-01

The aim of this study was to evaluate the effectiveness and toxicities of three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), and volumetric-modulated arc therapy (VMAT) in patients with cervical esophageal cancer. Specifically, we asked whether technological advances conferred an advantage with respect to the clinical curative effect. Seventy-eight patients with cervical esophageal cancer treated with definitive radiotherapy with or without concomitant chemotherapy at our institution between 2007 and 2014 were enrolled in the study: 26 received 3DCRT, 30 were treated with IMRT, and 22 underwent VMAT. Kaplan-Meier analysis and the Cox proportional hazard model were used to analyze overall survival (OS) and failure-free survival (FFS). Treatment-related toxicity was also assessed. For all patients, the 2-year OS and FFS rates were 56.2 and 53.9%, respectively. The 2-year OS for the 3DCRT, IMRT, and VMAT groups was 53.6, 55.6, and 60.6%, respectively (P = 0.965). The corresponding 2-year FFS rates were 49.5, 56.7, and 60.1% (P = 0.998). A univariate analysis of the complete response to treatment showed an advantage of treatment modality with respect to OS (P < 0.001). The development of acute hematologic toxicity was not significantly different among the three groups. The survival rates of patients treated with IMRT and VMAT were comparable to the survival of patients administered 3DCRT, while lower lung mean dose, V20, maximum dose of brachial plexus and spinal cord. Grade 1 radiation pneumonitis occurred significantly less in patients treated with IMRT and VMAT than with 3DCRT (P = 0.011). A complete response was the most important prognostic factor of the patients with cervical esophageal cancer. © 2016 International Society for Diseases of the Esophagus.

An automated dose tracking system for adaptive radiation therapy.

PubMed

Liu, Chang; Kim, Jinkoo; Kumarasiri, Akila; Mayyas, Essa; Brown, Stephen L; Wen, Ning; Siddiqui, Farzan; Chetty, Indrin J

2018-02-01

The implementation of adaptive radiation therapy (ART) into routine clinical practice is technically challenging and requires significant resources to perform and validate each process step. The objective of this report is to identify the key components of ART, to illustrate how a specific automated procedure improves efficiency, and to facilitate the routine clinical application of ART. Data was used from patient images, exported from a clinical database and converted to an intermediate format for point-wise dose tracking and accumulation. The process was automated using in-house developed software containing three modularized components: an ART engine, user interactive tools, and integration tools. The ART engine conducts computing tasks using the following modules: data importing, image pre-processing, dose mapping, dose accumulation, and reporting. In addition, custom graphical user interfaces (GUIs) were developed to allow user interaction with select processes such as deformable image registration (DIR). A commercial scripting application programming interface was used to incorporate automated dose calculation for application in routine treatment planning. Each module was considered an independent program, written in C++or C#, running in a distributed Windows environment, scheduled and monitored by integration tools. The automated tracking system was retrospectively evaluated for 20 patients with prostate cancer and 96 patients with head and neck cancer, under institutional review board (IRB) approval. In addition, the system was evaluated prospectively using 4 patients with head and neck cancer. Altogether 780 prostate dose fractions and 2586 head and neck cancer dose fractions went processed, including DIR and dose mapping. On average, daily cumulative dose was computed in 3 h and the manual work was limited to 13 min per case with approximately 10% of cases requiring an additional 10 min for image registration refinement. An efficient and convenient

A practical three-dimensional dosimetry system for radiation therapy

SciTech Connect

Guo Pengyi; Adamovics, John; Oldham, Mark

2006-10-15

There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE trade mark sign ) and a commercial optical computed tomography (CT) scanning system (OCTOPUS trade mark sign ). PRESAGE trade mark sign is a transparent material with compelling properties for dosimetry, including insensitivity of the dose response to atmospheric exposure, a solid texture negating the need formore » an external container (reducing edge effects), and amenability to accurate optical CT scanning due to radiochromic optical contrast as opposed to light-scattering contrast. An evaluation of the performance and viability of the PRESAGE trade mark sign /OCTOPUS, combination for routine clinical 3D dosimetry is presented. The performance of the two components (scanner and dosimeter) was investigated separately prior to full system test. The optical CT scanner has a spatial resolution of {<=}1 mm, geometric accuracy within 1 mm, and high reconstruction linearity (with a R{sup 2} value of 0.9979 and a standard error of estimation of {approx}1%) relative to independent measurement. The overall performance of the PRESAGE trade mark sign /OCTOPUS system was evaluated with respect to a simple known 3D dose distribution, by comparison with GAFCHROMIC[reg] EBT film and the calculated dose from a commissioned planning system. The 'measured' dose distribution in a cylindrical PRESAGE trade mark sign dosimeter (16 cm diameter and 11 cm height) was determined by optical-CT, using a filtered backprojection reconstruction algorithm. A three-way Gamma map comparison (4% dose difference and 4 mm distance to agreement), between the PRESAGE trade mark sign , EBT and calculated dose distributions, showed

Local Control After Stereotactic Body Radiation Therapy for Liver Tumors.

PubMed

Ohri, Nitin; Tomé, Wolfgang A; Méndez Romero, Alejandra; Miften, Moyed; Ten Haken, Randall K; Dawson, Laura A; Grimm, Jimm; Yorke, Ellen; Jackson, Andrew

2018-01-06

To quantitatively evaluate published experiences with hepatic stereotactic body radiation therapy (SBRT), to determine local control rates after treatment of primary and metastatic liver tumors and to examine whether outcomes are affected by SBRT dosing regimen. We identified published articles that reported local control rates after SBRT for primary or metastatic liver tumors. Biologically effective doses (BEDs) were calculated for each dosing regimen using the linear-quadratic equation. We excluded series in which a wide range of BEDs was used. Individual lesion data for local control were extracted from actuarial survival curves, and data were aggregated to form a single dataset. Actuarial local control curves were generated using the Kaplan-Meier method after grouping lesions by disease type and BED (<100 Gy 10 vs >100 Gy 10 ). Comparisons were made using log-rank testing. Thirteen articles met all inclusion criteria and formed the dataset for this analysis. The 1-, 2-, and 3-year actuarial local control rates after SBRT for primary liver tumors (n = 431) were 93%, 89%, and 86%, respectively. Lower 1- (90%), 2- (79%), and 3-year (76%) actuarial local control rates were observed for liver metastases (n = 290, log-rank P = .011). Among patients treated with SBRT for primary liver tumors, there was no evidence that local control is influenced by BED within the range of schedules used. For liver metastases, on the other hand, outcomes were significantly better for lesions treated with BEDs exceeding 100 Gy 10 (3-year local control 93%) than for those treated with BEDs of ≤100 Gy 10 (3-year local control 65%, P < .001). Stereotactic body radiation therapy for primary liver tumors provides high rates of durable local control, with no clear evidence for a dose-response relationship among commonly utilized schedules. Excellent local control rates are also seen after SBRT for liver metastases when BEDs of >100 Gy 10 are utilized. Copyright © 2018

Energy optimization in gold nanoparticle enhanced radiation therapy.

PubMed

Sung, Wonmo; Schuemann, Jan

2018-06-25

Gold nanoparticles (GNPs) have been demonstrated as radiation dose enhancing agents. Kilovoltage external photon beams have been shown to yield the largest enhancement due to the high interaction probability with gold. While orthovoltage irradiations are feasible and promising, they suffer from a reduced tissue penetrating power. This study quantifies the effect of varying photon beam energies on various beam arrangements, body, tumor, and cellular GNP uptake geometries. Cell survival was modeled based on our previously developed GNP-local effect model with radial doses calculated using the TOPAS-nBio Monte Carlo code. Cell survival curves calculated for tumor sites with GNPs were used to calculate the relative biological effectiveness (RBE)-weighted dose. In order to evaluate the plan quality, the ratio of the mean dose between the tumor and normal tissue for 50-250 kVp beams with GNPs was compared to the standard of care using 6 MV photon beams without GNPs for breast and brain tumors. For breast using a single photon beam, kV  +  GNP was found to yield up to 2.73 times higher mean RBE-weighted dose to the tumor than two tangential megavoltage beams while delivering the same dose to healthy tissue. For irradiation of brain tumors using multiple photon beams, the GNP dose enhancement was found to be effective for energies above 50 keV. A small tumor at shallow depths was found to be the most effective treatment conditions for GNP enhanced radiation therapy. GNP uptake distributions in the cell (with or without nuclear uptake) and the beam arrangement were found to be important factors in determining the optimal photon beam energy.

Current role of radiation therapy for multiple myeloma.

PubMed

Talamo, Giampaolo; Dimaio, Christopher; Abbi, Kamal K S; Pandey, Manoj K; Malysz, Jozef; Creer, Michael H; Zhu, Junjia; Mir, Muhammad A; Varlotto, John M

2015-01-01

Radiation therapy (RT) is a treatment modality traditionally used in patients with multiple myeloma (MM), but little is known regarding the role and effectiveness of RT in the era of novel agents, i.e., immunomodulatory drugs and proteasome inhibitors. We retrospectively reviewed data from 449 consecutive MM patients seen at our institute in 2010-2012 to assess indications for RT as well as its effectiveness. Pain response was scored similarly to RTOG 0631 and used the Numerical Rating Pain Scale. Among 442 evaluable patients, 149 (34%) patients and 262 sites received RT. The most common indication for RT was palliation of bone pain (n = 109, 42%), followed by prevention/treatment of pathological fractures (n = 73, 28%), spinal cord compression (n = 26, 10%), and involvement of vital organs/extramedullary disease (n = 25, 10%). Of the 55 patients evaluable for pain relief, complete and partial responses were obtained in 76.4 and 7.2%, respectively. Prior RT did not significantly decrease the median number of peripheral blood stem cells collected for autologous transplant, even when prior RT was given to both the spine and pelvis. Inadequacy of stem cell collection for autologous stem cell transplant (ASCT) was not significantly different and it occurred in 9 and 15% of patients receiving no RT and spine/pelvic RT, respectively. None of the three cases of therapy-induced acute myelogenous leukemia/MDS occurred in the RT group. Despite the introduction of novel effective agents in the treatment of MM, RT remains a major therapeutic component for the management in 34% of patients, and it effectively provides pain relief while not interfering with successful peripheral blood stem cell collection for ASCT.

Current Role of Radiation Therapy for Multiple Myeloma

PubMed Central

Talamo, Giampaolo; Dimaio, Christopher; Abbi, Kamal K. S.; Pandey, Manoj K.; Malysz, Jozef; Creer, Michael H.; Zhu, Junjia; Mir, Muhammad A.; Varlotto, John M.

2015-01-01

Background: Radiation therapy (RT) is a treatment modality traditionally used in patients with multiple myeloma (MM), but little is known regarding the role and effectiveness of RT in the era of novel agents, i.e., immunomodulatory drugs and proteasome inhibitors. Methods: We retrospectively reviewed data from 449 consecutive MM patients seen at our institute in 2010–2012 to assess indications for RT as well as its effectiveness. Pain response was scored similarly to RTOG 0631 and used the Numerical Rating Pain Scale. Results: Among 442 evaluable patients, 149 (34%) patients and 262 sites received RT. The most common indication for RT was palliation of bone pain (n = 109, 42%), followed by prevention/treatment of pathological fractures (n = 73, 28%), spinal cord compression (n = 26, 10%), and involvement of vital organs/extramedullary disease (n = 25, 10%). Of the 55 patients evaluable for pain relief, complete and partial responses were obtained in 76.4 and 7.2%, respectively. Prior RT did not significantly decrease the median number of peripheral blood stem cells collected for autologous transplant, even when prior RT was given to both the spine and pelvis. Inadequacy of stem cell collection for autologous stem cell transplant (ASCT) was not significantly different and it occurred in 9 and 15% of patients receiving no RT and spine/pelvic RT, respectively. None of the three cases of therapy-induced acute myelogenous leukemia/MDS occurred in the RT group. Conclusion: Despite the introduction of novel effective agents in the treatment of MM, RT remains a major therapeutic component for the management in 34% of patients, and it effectively provides pain relief while not interfering with successful peripheral blood stem cell collection for ASCT. PMID:25741475

Stereotactic Body Radiation Therapy in Recurrent Hepatocellular Carcinoma

SciTech Connect

Huang, Wen-Yen; Jen, Yee-Min, E-mail: yeeminjen@yahoo.com.tw; Lee, Meei-Shyuan

2012-10-01

Purpose: To examine the safety and efficacy of Cyberknife stereotactic body radiation therapy (SBRT) and its effect on survival in patients of recurrent hepatocellular carcinoma (HCC). Methods and Materials: This was a matched-pair study. From January 2008 to December 2009, 36 patients with 42 lesions of unresectable recurrent HCC were treated with SBRT. The median prescribed dose was 37 Gy (range, 25 to 48 Gy) in 4-5 fractions over 4-5 consecutive working days. Another 138 patients in the historical control group given other or no treatments were selected for matched analyses. Results: The median follow-up time was 14 months formore » all patients and 20 months for those alive. The 1- and 2-year in-field failure-free rates were 87.6% and 75.1%, respectively. Out-field intrahepatic recurrence was the main cause of failure. The 2-year overall survival (OS) rate was 64.0%, and median time to progression was 8.0 months. In the multivariable analysis of all 174 patients, SBRT (yes vs. no), tumor size ({<=}4 cm vs. >4 cm), recurrent stage (stage IIIB/IV vs. I) and Child-Pugh classification (A vs. B/C) were independent prognostic factors for OS. Matched-pair analysis revealed that patients undergoing SBRT had better OS (2-year OS of 72.6% vs. 42.1%, respectively, p = 0.013). Acute toxicities were mild and tolerable. Conclusion: SBRT is a safe and efficacious modality and appears to be well-tolerated at the dose fractionation we have used, and its use correlates with improved survival in this cohort of patients with recurrent unresectable HCC. Out-field recurrence is the major cause of failure. Further studies of combinations of SBRT and systemic therapies may be reasonable.« less

Projections onto the Pareto surface in multicriteria radiation therapy optimization

SciTech Connect

Bokrantz, Rasmus, E-mail: bokrantz@kth.se, E-mail: rasmus.bokrantz@raysearchlabs.com; Miettinen, Kaisa

2015-10-15

Purpose: To eliminate or reduce the error to Pareto optimality that arises in Pareto surface navigation when the Pareto surface is approximated by a small number of plans. Methods: The authors propose to project the navigated plan onto the Pareto surface as a postprocessing step to the navigation. The projection attempts to find a Pareto optimal plan that is at least as good as or better than the initial navigated plan with respect to all objective functions. An augmented form of projection is also suggested where dose–volume histogram constraints are used to prevent that the projection causes a violation ofmore » some clinical goal. The projections were evaluated with respect to planning for intensity modulated radiation therapy delivered by step-and-shoot and sliding window and spot-scanned intensity modulated proton therapy. Retrospective plans were generated for a prostate and a head and neck case. Results: The projections led to improved dose conformity and better sparing of organs at risk (OARs) for all three delivery techniques and both patient cases. The mean dose to OARs decreased by 3.1 Gy on average for the unconstrained form of the projection and by 2.0 Gy on average when dose–volume histogram constraints were used. No consistent improvements in target homogeneity were observed. Conclusions: There are situations when Pareto navigation leaves room for improvement in OAR sparing and dose conformity, for example, if the approximation of the Pareto surface is coarse or the problem formulation has too permissive constraints. A projection onto the Pareto surface can identify an inaccurate Pareto surface representation and, if necessary, improve the quality of the navigated plan.« less

Hypofractionated Radiation Therapy for Breast Ductal Carcinoma In Situ

SciTech Connect

Hathout, Lara; Hijal, Tarek; Théberge, Valérie

2013-12-01

Purpose: Conventional radiation therapy (RT) administered in 25 fractions after breast-conserving surgery (BCS) is the standard treatment for ductal carcinoma in situ (DCIS) of the breast. Although accelerated hypofractionated regimens in 16 fractions have been shown to be equivalent to conventional RT for invasive breast cancer, few studies have reported results of using hypofractionated RT in DCIS. Methods and Materials: In this multicenter collaborative effort, we retrospectively reviewed the records of all women with DCIS at 3 institutions treated with BCS followed by hypofractionated whole-breast RT (WBRT) delivered in 16 fractions. Results: Between 2003 and 2010, 440 patients with DCISmore » underwent BCS followed by hypofractionated WBRT in 16 fractions for a total dose of 42.5 Gy (2.66 Gy per fraction). Boost RT to the surgical bed was given to 125 patients (28%) at a median dose of 10 Gy in 4 fractions (2.5 Gy per fraction). After a median follow-up time of 4.4 years, 14 patients had an ipsilateral local relapse, resulting in a local recurrence-free survival of 97% at 5 years. Positive surgical margins, high nuclear grade, age less than 50 years, and a premenopausal status were all statistically associated with an increased occurrence of local recurrence. Tumor hormone receptor status, use of adjuvant hormonal therapy, and administration of additional boost RT did not have an impact on local control in our cohort. On multivariate analysis, positive margins, premenopausal status, and nuclear grade 3 tumors had a statistically significant worse local control rate. Conclusions: Hypofractionated RT using 42.5 Gy in 16 fractions provides excellent local control for patients with DCIS undergoing BCS.« less

Fluence field modulated CT on a clinical TomoTherapy radiation therapy machine

NASA Astrophysics Data System (ADS)

Szczykutowicz, Timothy P.; Hermus, James

2015-03-01

Purpose: The multi-leaf collimator (MLC) assembly present on TomoTherapy (Accuray, Madison WI) radiation therapy (RT) and mega voltage CT machines is well suited to perform fluence field modulated CT (FFMCT). In addition, there is a demand in the RT environment for FFMCT imaging techniques, specifically volume of interest (VOI) imaging. Methods: A clinical TomoTherapy machine was programmed to deliver 30% imaging dose outside predefined VOIs. Four different size ROIs were placed at varying distances from isocenter. Projections intersecting the VOI received "full dose" while those not intersecting the VOI received 30% of the dose (i.e. the incident fluence for non VOI projections was 30% of the incident fluence for projections intersecting the VOI). Additional scans without fluence field modulation were acquired at "full" and 30% dose. The noise (pixel standard deviation) was measured inside the VOI region and compared between the three scans. Results: The VOI-FFMCT technique produced an image noise 1.09, 1.05, 1.05, and 1.21 times higher than the "full dose" scan for ROI sizes of 10 cm, 13 cm, 10 cm, and 6 cm respectively within the VOI region. Conclusions: Noise levels can be almost unchanged within clinically relevant VOIs sizes for RT applications while the integral imaging dose to the patient can be decreased, and/or the image quality in RT can be dramatically increased with no change in dose relative to non-FFMCT RT imaging. The ability to shift dose away from regions unimportant for clinical evaluation in order to improve image quality or reduce imaging dose has been demonstrated. This paper demonstrates that FFMCT can be performed using the MLC on a clinical TomoTherapy machine for the first time.

Mometasone Furoate Cream Reduces Acute Radiation Dermatitis in Patients Receiving Breast Radiation Therapy: Results of a Randomized Trial

SciTech Connect

Hindley, Andrew, E-mail: andrew.hindley@lthtr.nhs.uk; Zain, Zakiyah; Wood, Lisa

Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MFmore » than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected.« less

The Impact of Radiation Oncologists on the Early Adoption of Hypofractionated Radiation Therapy for Early-Stage Breast Cancer.

PubMed

Boero, Isabel J; Gillespie, Erin F; Hou, Jiayi; Paravati, Anthony J; Kim, Ellen; Einck, John P; Yashar, Catheryn; Mell, Loren K; Murphy, James D

2017-03-01

Despite multiple randomized trials showing the efficacy of hypofractionated radiation therapy in early-stage breast cancer, the United States has been slow to adopt this treatment. The goal of this study was to evaluate the impact of individual radiation oncologists on the early adoption of hypofractionated radiation therapy for early-stage breast cancer. We identified 22,233 Medicare beneficiaries with localized breast cancer that was diagnosed from 2004 to 2011 who underwent breast-conserving surgery with adjuvant radiation. Multilevel, multivariable logistic models clustered by radiation oncologist and geographic practice area were used to determine the impact of the provider and geographic region on the likelihood of receiving hypofractionated compared with standard fractionated radiation therapy while controlling for a patient's clinical and demographic covariates. Odds ratios (OR) describe the impact of demographic or clinical covariates, and the median OR (MOR) describes the relative impact of the individual radiation oncologist and geographic region on the likelihood of undergoing hypofractionated radiation therapy. Among the entire cohort, 2333 women (10.4%) were treated with hypofractionated radiation therapy, with unadjusted rates ranging from 0.0% in the bottom quintile of radiation oncologists to 30.4% in the top quintile. Multivariable analysis found that the individual radiation oncologist (MOR 3.08) had a greater impact on the use of hypofractionation than did geographic region (MOR 2.10) or clinical and demographic variables. The impact of the provider increased from the year 2004 to 2005 (MOR 2.82) to the year 2010 to 2011 (MOR 3.16) despite the publication of long-term randomized trial results in early 2010. Male physician and radiation oncologists treating the highest volume of breast cancer patients were less likely to perform hypofractionation (P<.05). The individual radiation oncologist strongly influenced the likelihood of a patient

Airway complications after covered stent placement for malignant esophageal stricture: special reference to radiation therapy.

PubMed

Park, Ji Yeon; Shin, Ji Hoon; Song, Ho-Young; Yi, Seong Yoon; Kim, Jin Hyoung

2012-02-01

The purpose of this study was to evaluate the characteristics of airway complications and survival with special reference to radiation therapy in the care of patients undergoing covered stent placement for malignant esophageal strictures. A total of 208 patients who underwent stent placement with or without palliative radiation therapy for inoperable esophageal cancer were included. The endpoints were frequency, type, and management of airway complications; association between occurrence of airway complications and radiation therapy history; and differences in stent-to-complication interval and survival period after esophageal stenting between patients who underwent radiation therapy before and those who underwent radiation therapy after stent placement. Airway complications occurred in 23 patients (11.1%): 18 (78.3%) had esophagorespiratory fistula, three (13.0%) had airway narrowing, and two (8.7%) had both complications. The frequency of airway complications was significantly greater among patients who underwent RT than those who did not (p = 0.005) but was not significantly different between the radiation before stenting and radiation after stenting groups (p = 0.158). The median stent-to-complication interval and survival period after esophageal stenting were significantly shorter in the radiation before stenting group than in the radiation after stenting group (p = 0.002, p = 0.001). Esophagorespiratory fistula is much more common than airway narrowing as an airway complication. The rate of complications increases significantly in association with radiation therapy among patients with malignant esophageal stricture. Clinicians need to be aware of earlier airway complications and poorer prognosis among patients who undergo radiation therapy before placement of an esophageal stent than in patients who undergo radiation after stent placement.

Late esophageal toxicity after radiation therapy for head and neck cancer.

PubMed

Chen, Allen M; Li, Bao-Qing; Jennelle, Richard L S; Lau, Derick H; Yang, Claus C; Courquin, Jean; Vijayakumar, Srinivasan; Purdy, James A

2010-02-01

The aim of this study was to determine the incidence of esophageal toxicity after radiation therapy for head and neck cancer. The records of 211 patients treated by radiation therapy for head and neck cancer were reviewed to identify those with dysphagia lasting more than 90 days after therapy. Late toxicity criteria established by the Radiation Therapy Oncology Group were used to score the symptoms. The incidence of grade 3+ esophageal toxicity at 3 and 6 months was 30% and 19%, respectively. The rate of gastrotomy-tube dependence at 3 and 6 months was 20% and 11%, respectively. Hypopharyngeal and unknown primary site (p = .01, for both), T4 disease (p = .01), and the use of concurrent chemotherapy (p = .001) were associated with grade 3+ esophageal toxicity and stricture formation. A significant proportion of patients exhibit symptoms of esophageal toxicity after radiation therapy for head and neck cancer. Therefore, preventive strategies need further investigation. Copyright 2009 Wiley Periodicals, Inc.

Cherenkov Video Imaging Allows for the First Visualization of Radiation Therapy in Real Time

SciTech Connect

Jarvis, Lesley A., E-mail: Lesley.a.jarvis@hitchcock.org; Norris Cotton Cancer Center at the Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire; Zhang, Rongxiao

Purpose: To determine whether Cherenkov light imaging can visualize radiation therapy in real time during breast radiation therapy. Methods and Materials: An intensified charge-coupled device (CCD) camera was synchronized to the 3.25-μs radiation pulses of the clinical linear accelerator with the intensifier set × 100. Cherenkov images were acquired continuously (2.8 frames/s) during fractionated whole breast irradiation with each frame an accumulation of 100 radiation pulses (approximately 5 monitor units). Results: The first patient images ever created are used to illustrate that Cherenkov emission can be visualized as a video during conditions typical for breast radiation therapy, even with complex treatment plans,more » mixed energies, and modulated treatment fields. Images were generated correlating to the superficial dose received by the patient and potentially the location of the resulting skin reactions. Major blood vessels are visible in the image, providing the potential to use these as biological landmarks for improved geometric accuracy. The potential for this system to detect radiation therapy misadministrations, which can result from hardware malfunction or patient positioning setup errors during individual fractions, is shown. Conclusions: Cherenkoscopy is a unique method for visualizing surface dose resulting in real-time quality control. We propose that this system could detect radiation therapy errors in everyday clinical practice at a time when these errors can be corrected to result in improved safety and quality of radiation therapy.« less

Drug-, toxin-, and radiation therapy-induced eosinophilic pneumonia.

PubMed

Solomon, Joshua; Schwarz, Marvin

2006-04-01

A significant number of drugs and toxins have been associated with eosinophilic pneumonia. Antibiotics and NSAID, are the most commonly reported drugs. Toxins suspected to cause eosinophilic pneumonia include cigarette smoke and illicit drugs. Drug- or toxin-induced eosinophilic pneumonia is indistinguishable from idiopathic acute or chronic eosinophilic pneumonia by clinical, radiographic, and histopathologic criteria. The diagnosis is supported by a temporal relationship to a drug or toxin. The condition usually resolves with removal from the agent and recurs with rechallenge. Treatment involves discontinuation of the offending drug or toxin and treatment with corticosteroids in severe respiratory failure. There are also mass outbreaks of eosinophilic pneumonia reported, such as the toxic-oil syndrome in 1981 and the eosinophilia-myalgia syndrome related to the ingestion of L-tryptophan in 1989. A recent report has described an outbreak of acute eosinophilic pneumonia found in soldiers in Iraq. Radiation therapy has also been associated with the development of eosinophilic pneumonia in patients receiving this treatment for breast cancer.

Objective Assessment of Image Quality VI: Imaging in Radiation Therapy

PubMed Central

Barrett, Harrison H.; Kupinski, Matthew A.; Müeller, Stefan; Halpern, Howard J.; Morris, John C.; Dwyer, Roisin

2015-01-01

Earlier work on Objective Assessment of Image Quality (OAIQ) focused largely on estimation or classification tasks in which the desired outcome of imaging is accurate diagnosis. This paper develops a general framework for assessing imaging quality on the basis of therapeutic outcomes rather than diagnostic performance. By analogy to Receiver Operating Characteristic (ROC) curves and their variants as used in diagnostic OAIQ, the method proposed here utilizes the Therapy Operating Characteristic or TOC curves, which are plots of the probability of tumor control vs. the probability of normal-tissue complications as the overall dose level of a radiotherapy treatment is varied. The proposed figure of merit is the area under the TOC curve, denoted AUTOC. This paper reviews an earlier exposition of the theory of TOC and AUTOC, which was specific to the assessment of image-segmentation algorithms, and extends it to other applications of imaging in external-beam radiation treatment as well as in treatment with internal radioactive sources. For each application, a methodology for computing the TOC is presented. A key difference between ROC and TOC is that the latter can be defined for a single patient rather than a population of patients. PMID:24200954

Biological imaging in radiation therapy: role of positron emission tomography.

PubMed

Nestle, Ursula; Weber, Wolfgang; Hentschel, Michael; Grosu, Anca-Ligia

2009-01-07

In radiation therapy (RT), staging, treatment planning, monitoring and evaluation of response are traditionally based on computed tomography (CT) and magnetic resonance imaging (MRI). These radiological investigations have the significant advantage to show the anatomy with a high resolution, being also called anatomical imaging. In recent years, so called biological imaging methods which visualize metabolic pathways have been developed. These methods offer complementary imaging of various aspects of tumour biology. To date, the most prominent biological imaging system in use is positron emission tomography (PET), whose diagnostic properties have clinically been evaluated for years. The aim of this review is to discuss the valences and implications of PET in RT. We will focus our evaluation on the following topics: the role of biological imaging for tumour tissue detection/delineation of the gross tumour volume (GTV) and for the visualization of heterogeneous tumour biology. We will discuss the role of fluorodeoxyglucose-PET in lung and head and neck cancer and the impact of amino acids (AA)-PET in target volume delineation of brain gliomas. Furthermore, we summarize the data of the literature about tumour hypoxia and proliferation visualized by PET. We conclude that, regarding treatment planning in radiotherapy, PET offers advantages in terms of tumour delineation and the description of biological processes. However, to define the real impact of biological imaging on clinical outcome after radiotherapy, further experimental, clinical and cost/benefit analyses are required.

[Big data and their perspectives in radiation therapy].

PubMed

Guihard, Sébastien; Thariat, Juliette; Clavier, Jean-Baptiste

2017-02-01

The concept of big data indicates a change of scale in the use of data and data aggregation into large databases through improved computer technology. One of the current challenges in the creation of big data in the context of radiation therapy is the transformation of routine care items into dark data, i.e. data not yet collected, and the fusion of databases collecting different types of information (dose-volume histograms and toxicity data for example). Processes and infrastructures devoted to big data collection should not impact negatively on the doctor-patient relationship, the general process of care or the quality of the data collected. The use of big data requires a collective effort of physicians, physicists, software manufacturers and health authorities to create, organize and exploit big data in radiotherapy and, beyond, oncology. Big data involve a new culture to build an appropriate infrastructure legally and ethically. Processes and issues are discussed in this article. Copyright © 2016 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

Radiation therapy for mucosal melanoma of the head and neck.

PubMed

Christopherson, Kaitlin; Malyapa, Robert S; Werning, John W; Morris, Christopher G; Kirwan, Jessica; Mendenhall, William M

2015-02-01

The aim of this study was to evaluate the long-term effectiveness and complications of radiotherapy (RT) in the treatment of patients with mucosal melanomas of the head and neck. The medical records of 21 patients treated with definitive or postoperative (RT) between 1974 and 2011 at the University of Florida Department of Radiation Oncology in Gainesville, FL, and the University of Florida Proton Therapy Institute in Jacksonville, FL, were retrospectively reviewed under an Institutional Review Board-approved protocol. Primary sites included nasal cavity, oropharynx, and paranasal sinuses. Sixteen patients (76%) received surgery and postoperative RT and 5 patients (24%) received RT alone. Seventeen patients received photon RT alone, whereas 4 patients received combined photon-based and proton-based RT. Median follow-up for all patients was 1.05 years (range, 0.36 to 12.97 y); median follow-up for survivors was 2.2 years (range 0.9 to 13.0 y). The 5-year outcomes were: local control, 79%; regional control, 85%; local-regional control, 65%; distant metastasis-free survival, 20%; cause-specific survival, 22%; and overall survival, 22%. Three patients (14%) experienced severe complications including bilateral blindness and skin necrosis. Definitive or postoperative RT for mucosal melanoma of the head and neck yields fairly good local-regional control of disease. The prognosis for patients treated with definitive RT is less promising than for those who receive surgery and postoperative RT.

Prostate Cancer Radiation Therapy and Risk of Thromboembolic Events

SciTech Connect

Bosco, Cecilia, E-mail: Cecilia.t.bosco@kcl.ac.uk; Garmo, Hans; Regional Cancer Centre, Uppsala, Akademiska Sjukhuset, Uppsala

Purpose: To investigate the risk of thromboembolic disease (TED) after radiation therapy (RT) with curative intent for prostate cancer (PCa). Patients and Methods: We identified all men who received RT as curative treatment (n=9410) and grouped according to external beam RT (EBRT) or brachytherapy (BT). By comparing with an age- and county-matched comparison cohort of PCa-free men (n=46,826), we investigated risk of TED after RT using Cox proportional hazard regression models. The model was adjusted for tumor characteristics, demographics, comorbidities, PCa treatments, and known risk factors of TED, such as recent surgery and disease progression. Results: Between 2006 and 2013, 6232more » men with PCa received EBRT, and 3178 underwent BT. A statistically significant association was found between EBRT and BT and risk of pulmonary embolism in the crude analysis. However, upon adjusting for known TED risk factors these associations disappeared. No significant associations were found between BT or EBRT and deep venous thrombosis. Conclusion: Curative RT for prostate cancer using contemporary methodologies was not associated with an increased risk of TED.« less

Acid ceramidase in prostate cancer radiation therapy resistance and relapse

NASA Astrophysics Data System (ADS)

Cheng, Joseph C.

Prostate tumor cell escape from ionizing radiation (IR)-induced killing can lead to disease progression and relapse. Sphingolipids such as ceramide and sphingosine 1-phosphate influence signal transduction pathways that regulate stress response in cancer cells. In particular, metabolism of apoptotic ceramide constitutes an important survival adaptation. Assessments of enzyme activity, mRNA, and protein demonstrated preferential upregulation of the ceramide deacylating enzyme acid ceramidase (AC) in irradiated cancer cells. Promoter-reporter and ChIP-qPCR assays revealed AC transcription by activator protein 1 (AP-1) is sensitive to pharmacological inhibition of de novo ceramide biosynthesis, identifying a protective feedback mechanism that mitigates the effects of IR-induced ceramide. Deregulation of c-Jun, in particular, induced marked radiosensitization in vitro and in vivo, which was rescued by ectopic AC over-expression. AC over-expression in prostate cancer clonogens surviving 80 Gray fractionated irradiation was associated with increased radioresistance and proliferation, suggesting a role in radiotherapy failure and relapse. Indeed, immunohistochemical analysis of human prostate cancer tissues revealed higher levels of AC after radiotherapy failure than therapy-naive adenocarcinoma, PIN, or benign tissues. By genetically downregulating AC with small interfering RNA (siRNA), we observed radiosensitization of cells using clonogenic and cytotoxicity assays. Finally, treatment with lysosomotropic small molecule inhibitors of AC, LCL385 or LCL521, induced prostate cancer xenograft radiosensitization and long-term suppression, suggesting AC is a tractable target for adjuvant radiotherapy.

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System

SciTech Connect

Eigler, N.; Whiting, J.; Chernomorsky, A.

1998-01-16

RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Milliporemore » filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.« less

Radiation therapy for gastric wall metastasis from esophageal carcinoma.

PubMed

Hashimoto, Naoko; Iwazawa, Jin; Abe, Hisashi; Mitani, Takashi; Kagawa, Kazufumi

2010-04-01

An 86-year-old man with dysphagia underwent gastrointestinal fiberscopy (GIF) and was found to have a circumferential type 3 advanced carcinoma in the upper thoracic esophagus and a type 2 tumor in the posterior wall of the gastric body. Microscopic examination of biopsy specimens of both tumors demonstrated moderately differentiated squamous cell carcinoma. He was diagnosed as having stage IVb (T3N0M1b) esophageal carcinoma with gastric wall metastasis. A total of 60 Gy in 30 fractions of three-dimensional conformal radiation therapy (3D-CRT) was first administered to the esophageal carcinoma, next to the gastric wall metastasis. Concurrent chemotherapy was not given because of the patient's refusal. No subjective morbidity was observed during the treatment. In the GIF study immediately after 3D-CRT, both esophageal and gastric wall tumors had attained a complete response. The dysphagia dissolved as the esophageal tumor shrunk. The patient has been doing well for 17 months after the start of 3D-CRT. No local recurrence was observed in either the esophagus or the stomach during follow-up GIF. Considering the dismal prognosis of esophageal carcinoma patients with intramural metastasis to the stomach, a watchful follow-up is needed.

Prostate Cancer Radiation Therapy: What Do Clinicians Have to Know?

PubMed Central

Van Limbergen, Evert J.; van Lin, Emile N.; van Roermund, Joep G. H.; Lambin, Philippe

2016-01-01

Radiotherapy (RT) for prostate cancer (PC) has steadily evolved over the last decades, with improving biochemical disease-free survival. Recently population based research also revealed an association between overall survival and doses ≥ 75.6 Gray (Gy) in men with intermediate- and high-risk PC. Examples of improved RT techniques are image-guided RT, intensity-modulated RT, volumetric modulated arc therapy, and stereotactic ablative body RT, which could facilitate further dose escalation. Brachytherapy is an internal form of RT that also developed substantially. New devices such as rectum spacers and balloons have been developed to spare rectal structures. Newer techniques like protons and carbon ions have the intrinsic characteristics maximising the dose on the tumour while minimising the effect on the surrounding healthy tissue, but clinical data are needed for confirmation in randomised phase III trials. Furthermore, it provides an overview of an important discussion issue in PC treatment between urologists and radiation oncologists: the comparison between radical prostatectomy and RT. Current literature reveals that all possible treatment modalities have the same cure rate, but a different toxicity pattern. We recommend proposing the possible different treatment modalities with their own advantages and side-effects to the individual patient. Clinicians and patients should make treatment decisions together (shared decision-making) while using patient decision aids. PMID:28116302

Optimization and quality assurance of an image-guided radiation therapy system for intensity-modulated radiation therapy radiotherapy

SciTech Connect

Tsai, Jen-San, E-mail: jen-san.tsai@verizon.net; Micaily, Bizhan; Miyamoto, Curtis

2012-10-01

To develop a quality assurance (QA) of XVI cone beam system (XVIcbs) for its optimal imaging-guided radiotherapy (IGRT) implementation, and to construe prostate tumor margin required for intensity-modulated radiation therapy (IMRT) if IGRT is unavailable. XVIcbs spatial accuracy was explored with a humanoid phantom; isodose conformity to lesion target with a rice phantom housing a soap as target; image resolution with a diagnostic phantom; and exposure validation with a Radcal ion chamber. To optimize XVIcbs, rotation flexmap on coincidency between gantry rotational axis and that of XVI cone beam scan was investigated. Theoretic correlation to image quality of XVIcbs rotationalmore » axis stability was elaborately studied. Comprehensive QA of IGRT using XVIcbs has initially been explored and then implemented on our general IMRT treatments, and on special IMRT radiotherapies such as head and neck (H and N), stereotactic radiation therapy (SRT), stereotactic radiosurgery (SRS), and stereotactic body radiotherapy (SBRT). Fifteen examples of prostate setup accounted for 350 IGRT cone beam system were analyzed. IGRT accuracy results were in agreement {+-} 1 mm. Flexmap 0.25 mm met the manufacturer's specification. Films confirmed isodose coincidence with target (soap) via XVIcbs, otherwise not. Superficial doses were measured from 7.2-2.5 cGy for anatomic diameters 15-33 cm, respectively. Image quality was susceptible to rotational stability or patient movement. IGRT using XVIcbs on general IMRT treatments such as prostate, SRT, SRS, and SBRT for setup accuracy were verified; and subsequently coordinate shifts corrections were recorded. The 350 prostate IGRT coordinate shifts modeled to Gaussian distributions show central peaks deviated off the isocenter by 0.6 {+-} 3.0 mm, 0.5 {+-} 4.5 mm in the X(RL)- and Z(SI)-coordinates, respectively; and 2.0 {+-} 3.0 mm in the Y(AP)-coordinate as a result of belly and bladder capacity variations. Sixty-eight percent of

Use of Combination Thermal Therapy and Radiation in Breast-Conserving Treatment of Extensive Intraductal Breast Cancer

DTIC Science & Technology

1997-07-01

Review Board of the DFCI is provided in Appendix A . The investigator will keep the following information on each patient: 1. Past medical ...treatments, you will receive radiation therapy to your breast. Your radiation oncologist will decide what radiation dose you receive . On the basis of... Activities 6/87 Controversies in radiation therapy in

Effect of abdominopelvic abscess drain size on drainage time and probability of occlusion.

PubMed

Rotman, Jessica A; Getrajdman, George I; Maybody, Majid; Erinjeri, Joseph P; Yarmohammadi, Hooman; Sofocleous, Constantinos T; Solomon, Stephen B; Boas, F Edward

2017-04-01

The purpose of this study is to determine whether larger abdominopelvic abscess drains reduce the time required for abscess resolution or the probability of tube occlusion. 144 consecutive patients who underwent abscess drainage at a single institution were reviewed retrospectively. Larger initial drain size did not reduce drainage time, drain occlusion, or drain exchanges (P > .05). Subgroup analysis did not find any type of collection that benefitted from larger drains. A multivariate model predicting drainage time showed that large collections (>200 mL) required 16 days longer drainage time than small collections (<50 mL). Collections with a fistula to bowel required 17 days longer drainage time than collections without a fistula. Initial drain size and the viscosity of the fluid in the collection had no significant effect on drainage time in the multivariate model. 8 F drains are adequate for initial drainage of most serous and serosanguineous collections. 10 F drains are adequate for initial drainage of most purulent or bloody collections. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of abdominopelvic abscess drain size on drainage time and probability of occlusion

PubMed Central

Rotman, Jessica A.; Getrajdman, George I.; Maybody, Majid; Erinjeri, Joseph P.; Yarmohammadi, Hooman; Sofocleous, Constantinos T.; Solomon, Stephen B.; Boas, F. Edward

2016-01-01

Background The purpose of this study is to determine whether larger abdominopelvic abscess drains reduce the time required for abscess resolution, or the probability of tube occlusion. Methods 144 consecutive patients who underwent abscess drainage at a single institution were reviewed retrospectively. Results: Larger initial drain size did not reduce drainage time, drain occlusion, or drain exchanges (p>0.05). Subgroup analysis did not find any type of collection that benefitted from larger drains. A multivariate model predicting drainage time showed that large collections (>200 ml) required 16 days longer drainage time than small collections (<50 ml). Collections with a fistula to bowel required 17 days longer drainage time than collections without a fistula. Initial drain size and the viscosity of the fluid in the collection had no significant effect on drainage time in the multivariate model. Conclusions 8 F drains are adequate for initial drainage of most serous and serosanguineous collections. 10 F drains are adequate for initial drainage of most purulent or bloody collections. PMID:27634422

Clinical and computed tomography features of adult abdominopelvic desmoplastic small round cell tumor.

PubMed

Shen, Xun-Ze; Zhao, Jian-Guo; Wu, Jian-Jun; Liu, Fang

2014-05-07

To investigate the clinical and computed tomography (CT) features of desmoplastic small round cell tumor (DSRCT), we retrospectively analyzed the clinical presentations, treatment and outcome, as well as CT manifestations of four cases of DSRCT confirmed by surgery and pathology. The CT manifestations of DSRCT were as follows: (1) multiple soft-tissue masses or diffuse peritoneal thickening in the abdomen and pelvis, with the dominant mass usually located in the pelvic cavity; (2) masses without an apparent organ-based primary site; (3) mild to moderate homogeneous or heterogeneous enhancement in solid area on enhanced CT; and (4) secondary manifestations, such as ascites, hepatic metastases, lymphadenopathy, hydronephrosis and hydroureter. The prognosis and overall survival rates were generally poor. Commonly used treatment strategies including aggressive tumor resection, polychemotherapy, and radiotherapy, showed various therapeutic effects. CT of DSRCT shows characteristic features that are helpful in diagnosis. Early discovery and complete resection, coupled with postoperative adjuvant chemotherapy, are important for prognosis of DSRCT. Whole abdominopelvic rather than locoregional radiotherapy is more effective for unresectable DSRCT.

Imaging and characterization of primary and secondary radiation in ion beam therapy

NASA Astrophysics Data System (ADS)

Granja, Carlos; Martisikova, Maria; Jakubek, Jan; Opalka, Lukas; Gwosch, Klaus

2016-07-01

Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.

Intrafraction Motion in Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer: Intensity Modulated Radiation Therapy Versus Volumetric Modulated Arc Therapy

SciTech Connect

Rossi, Maddalena M.G.; Peulen, Heike M.U.; Belderbos, Josè S.A.

Purpose: Stereotactic body radiation therapy (SBRT) for early-stage inoperable non-small cell lung cancer (NSCLC) patients delivers high doses that require high-precision treatment. Typically, image guidance is used to minimize day-to-day target displacement, but intrafraction position variability is often not corrected. Currently, volumetric modulated arc therapy (VMAT) is replacing intensity modulated radiation therapy (IMRT) in many departments because of its shorter delivery time. This study aimed to evaluate whether intrafraction variation in VMAT patients is reduced in comparison with patients treated with IMRT. Methods and Materials: NSCLC patients (197 IMRT and 112 VMAT) treated with a frameless SBRT technique to amore » prescribed dose of 3 × 18 Gy were evaluated. Image guidance for both techniques was identical: pretreatment cone beam computed tomography (CBCT) (CBCT{sub precorr}) for setup correction followed immediately before treatment by postcorrection CBCT (CBCT{sub postcorr}) for verification. Then, after either a noncoplanar IMRT technique or a VMAT technique, a posttreatment (CBCT{sub postRT}) scan was acquired. The CBCT{sub postRT} and CBCT{sub postcorr} scans were then used to evaluate intrafraction motion. Treatment delivery times, systematic (Σ) and random (σ) intrafraction variations, and associated planning target volume (PTV) margins were calculated. Results: The median treatment delivery time was significantly reduced by 20 minutes (range, 32-12 minutes) using VMAT compared with noncoplanar IMRT. Intrafraction tumor motion was significantly larger for IMRT in all directions up to 0.5 mm systematic (Σ) and 0.7 mm random (σ). The required PTV margins for IMRT and VMAT differed by less than 0.3 mm. Conclusion: VMAT-based SBRT for NSCLC was associated with significantly shorter delivery times and correspondingly smaller intrafraction motion compared with noncoplanar IMRT. However, the impact on the required PTV margin was small.« less

Computed Tomography Density Change in the Thyroid Gland Before and After Radiation Therapy.

PubMed

Ishibashi, Naoya; Maebayashi, Toshiya; Aizawa, Takuya; Sakaguchi, Masakuni; Okada, Masahiro; Matsushita, Junichi

2018-01-01

Hypothyroidism is an established adverse effect of radiation therapy for head and neck cancer, and computed tomography (CT) density of the thyroid gland is lower in hypothyroid than euthyroid individuals. No previous studies have evaluated changes in CT densities of the thyroid gland caused by radiation therapy. The aim was to investigate the relationship between the change in CT density of the thyroid gland before and after radiation therapy for head and neck cancer and hypothyroidism. This retrospective study analyzed data of 24 patients treated by radiation therapy for head and neck cancers. After dosimetric analysis of received radiation therapy, a Picture Archiving and Communication System was used to manually contour the thyroid on pre-treatment CT images to enable determination of mean thyroid gland CT densities and received radiation doses. Pre- and post-treatment thyroid function was assessed on the basis of serum TSH concentrations. Multivariate and univariate analyses were used to determine what clinical factors are associated with post-radiation therapy decrease in CT density of the thyroid and Pearson's χ 2 test was used to assess correlations between these densities and TSH concentrations. Mean CT densities of the thyroid gland decreased from before to after radiation therapy in 73.9% of our patients (median decrease 16.8 HU). Serum TSH concentrations were significantly higher in patients with greater then median decreases in CT density than in those with lesser or no decreases. Post-radiation therapy hypothyroidism may be predicted by significant decreases in CT density of the thyroid gland. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Fetal radiation monitoring and dose minimization during intensity modulated radiation therapy for glioblastoma in pregnancy.

PubMed

Horowitz, David P; Wang, Tony J C; Wuu, Cheng-Shie; Feng, Wenzheng; Drassinower, Daphnie; Lasala, Anita; Pieniazek, Radoslaw; Cheng, Simon; Connolly, Eileen P; Lassman, Andrew B

2014-11-01

We examined the fetal dose from irradiation of glioblastoma during pregnancy using intensity modulated radiation therapy (IMRT), and describe fetal dose minimization using mobile shielding devices. A case report is described of a pregnant woman with glioblastoma who was treated during the third trimester of gestation with 60 Gy of radiation delivered via a 6 MV photon IMRT plan. Fetal dose without shielding was estimated using an anthropomorphic phantom with ion chamber and diode measurements. Clinical fetal dose with shielding was determined with optically stimulated luminescent dosimeters and ion chamber. Clinical target volume (CTV) and planning target volume (PTV) coverage was 100 and 98 % receiving 95 % of the prescription dose, respectively. Normal tissue tolerances were kept below quantitative analysis of normal tissue effects in the clinic (QUANTEC) recommendations. Without shielding, anthropomorphic phantom measurements showed a cumulative fetal dose of 0.024 Gy. In vivo measurements with shielding in place demonstrated a cumulative fetal dose of 0.016 Gy. The fetal dose estimated without shielding was 0.04 % and with shielding was 0.026 % of the target dose. In vivo estimation of dose equivalent received by the fetus was 24.21 mSv. Using modern techniques, brain irradiation can be delivered to pregnant patients in the third trimester with very low measured doses to the fetus, without compromising target coverage or normal tissue dose constraints. Fetal dose can further be reduced with the use of shielding devices, in keeping with the principle of as low as reasonably achievable.

Outcomes of Pediatric Low-grade Gliomas Treated With Radiation Therapy: A Single-institution Study

PubMed Central

Raikar, Sunil S.; Halloran, Donna R.; Elliot, Michael; McHugh, Michele; Patel, Shaun; Gauvain, Karen M.

2014-01-01

Summary Radiation therapy is often considered the treatment of choice for low-grade gliomas. However, given the long-term effects of radiation on the developing brain, the appropriate use of radiation therapy in pediatric patients remains controversial. The purpose of this study was to evaluate progression-free survival (PFS) of pediatric low-grade glioma patients treated with radiation therapy. Data were obtained through a retrospective chart review of patients treated between 1991 and 2008 from a single tertiary care center in the midwest. The study population consisted of 17 patients, of whom 8 (47%) had tumor recurrence after radiation therapy. The median follow-up time was 8.2 years, with a range of 2.3 to 17.2 years. The median age at diagnosis was 5.4 years, and the median age at radiation therapy was 9.4 years. The 3- and the 10-year PFS were 69% ± 11.7% and 46% ± 13.3%, respectively. A significant difference in PFS was seen when comparing brainstem tumors with hypothalamic/optic pathway tumors (P = 0.019). Differences in PFS based on the age at diagnosis, the extent of initial surgery, and indication for radiation therapy were not significant. A larger multicenter study is needed to better assess PFS in these patients. PMID:24714505

Evaluation of dog owners' perceptions concerning radiation therapy

PubMed Central

Denneberg, Nanna Åkerlund; Egenvall, Agneta

2009-01-01

Background External radiation therapy (RT) has been available for small animals in Sweden since 2006. This study was designed to obtain information on owner experiences and perceptions related to RT of cancer in their dogs. Another survey was used to determine the attitudes about use of RT in a group of Swedish veterinarians. Their responses were analyzed and compared to their level of knowledge of oncology and RT. Methods Owners of all dogs (n = 23) who had undergone RT for malignancy at Jönköping Small Animal Hospital between March 2006 to September 2007 were interviewed. A questionnaire was given to a selected group of veterinarians. Results All 23 owners responded. All owners thought that their dog did well during RT and most that their dog was also fine during the following phase when acute RT-related skin reactions occur and heal. Three owners stated that their dog had pain that negatively impacted quality of life because of radiation dermatitis. Five owners reported that RT positively impacted quality of life of the dog during the first weeks after RT because palliation was achieved. The owners were not disturbed by the efforts required of them. All but one owner (22 of 23) stated that they would make the same decision about RT again if a similar situation occurred. The most important factor for this decision was the chance to delay occurrence of tumour-related discomfort. The chance for cure was of less importance but still essential, followed by expected side effects. Time commitments, travel, number of treatments required and financial cost; all had low impact. The veterinarian survey showed that less background knowledge of small animal oncology/RT was associated with more negative expectations of RT for small animals. Conclusion The results show that for these owners, RT was a worthwhile treatment modality and that the discomfort for the dog was manageable and acceptable relative to the benefits. Improved continuing education about small animal RT in

Modern radiation therapy for Hodgkin lymphoma: field and dose guidelines from the international lymphoma radiation oncology group (ILROG).

PubMed

Specht, Lena; Yahalom, Joachim; Illidge, Tim; Berthelsen, Anne Kiil; Constine, Louis S; Eich, Hans Theodor; Girinsky, Theodore; Hoppe, Richard T; Mauch, Peter; Mikhaeel, N George; Ng, Andrea

2014-07-15

Radiation therapy (RT) is the most effective single modality for local control of Hodgkin lymphoma (HL) and an important component of therapy for many patients. These guidelines have been developed to address the use of RT in HL in the modern era of combined modality treatment. The role of reduced volumes and doses is addressed, integrating modern imaging with 3-dimensional (3D) planning and advanced techniques of treatment delivery. The previously applied extended field (EF) and original involved field (IF) techniques, which treated larger volumes based on nodal stations, have now been replaced by the use of limited volumes, based solely on detectable nodal (and extranodal extension) involvement at presentation, using contrast-enhanced computed tomography, positron emission tomography/computed tomography, magnetic resonance imaging, or a combination of these techniques. The International Commission on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided radiation therapy, and 4-dimensional imaging, should be implemented when their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control. The highly conformal involved node radiation therapy (INRT), recently introduced for patients for whom optimal imaging is available, is explained. A new concept, involved site radiation therapy (ISRT), is introduced as the standard conformal therapy for the scenario, commonly encountered, wherein optimal imaging is not available. There is increasing evidence that RT doses used in the past are higher than necessary for disease control in this era of combined modality therapy. The use of INRT and of lower doses in early-stage HL is supported by available data. Although the

Modern Radiation Therapy for Hodgkin Lymphoma: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group (ILROG)

SciTech Connect

Specht, Lena, E-mail: lena.specht@regionh.dk; Yahalom, Joachim; Illidge, Tim

2014-07-15

Radiation therapy (RT) is the most effective single modality for local control of Hodgkin lymphoma (HL) and an important component of therapy for many patients. These guidelines have been developed to address the use of RT in HL in the modern era of combined modality treatment. The role of reduced volumes and doses is addressed, integrating modern imaging with 3-dimensional (3D) planning and advanced techniques of treatment delivery. The previously applied extended field (EF) and original involved field (IF) techniques, which treated larger volumes based on nodal stations, have now been replaced by the use of limited volumes, based solelymore » on detectable nodal (and extranodal extension) involvement at presentation, using contrast-enhanced computed tomography, positron emission tomography/computed tomography, magnetic resonance imaging, or a combination of these techniques. The International Commission on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided radiation therapy, and 4-dimensional imaging, should be implemented when their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control. The highly conformal involved node radiation therapy (INRT), recently introduced for patients for whom optimal imaging is available, is explained. A new concept, involved site radiation therapy (ISRT), is introduced as the standard conformal therapy for the scenario, commonly encountered, wherein optimal imaging is not available. There is increasing evidence that RT doses used in the past are higher than necessary for disease control in this era of combined modality therapy. The use of INRT and of lower doses in early-stage HL is supported by available data

Academic and Resident Radiation Oncologists' Attitudes and Intentions Regarding Radiation Therapy near the End of Life.

PubMed

Lloyd, Shane; Dosoretz, Arie P; Yu, James B; Evans, Suzanne B; Decker, Roy H

2016-02-01

There has been increasing scrutiny about cancer treatment for patients very near the end of life (EoL), yet a substantial number receive palliative radiation therapy (RT) in this setting. Our aim was to document the attitudes and intentions of thought leaders and trainees in giving RT near the EoL. We distributed an anonymous survey to 473 radiation oncologists and residents. The survey examined the clinical and psychosocial factors considered as well as intentions and expectations in the delivery of RT near the EoL. Factors surrounding unfinished treatment courses, and the formative factors that shape opinions about RT at the EoL were also explored. We received 139 responses (29%). Eighty-nine percent of respondents worked at academic institutions. The factors that respondents most often consider very or extremely important to offer RT near the EoL were the preference of the patient to be treated (94%), the ability to tolerate treatment (88%), and palliative intent (70%). After instances when their patients were unable to complete treatment near the EoL, 42% of respondents said they would prescribe a shorter treatment the next time they see a similar patient. Personal experience (71%) was most often listed as very or extremely important in shaping their opinions about RT near the EoL. Survey respondents, 89% of whom were academic radiation oncologists, have a positive view of palliative RT near the EoL. They favor shorter fractionation for patients near the EoL. Personal experience is most important in shaping practices and attitudes.

The promise of dynamic contrast-enhanced imaging in radiation therapy.

PubMed

Cao, Yue

2011-04-01

Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and computed tomography (CT) scanning are emerging as valuable tools to quantitatively map the spatial distribution of vascular parameters, such as perfusion, vascular permeability, blood volume, and mean transit time in tumors and normal organs. DCE MRI/CT have shown prognostic and predictive value for response of certain cancers to chemotherapy and radiation therapy. DCE MRI/CT offer the promise of early assessment of tumor response to radiation therapy, opening a window for adaptively optimizing radiation therapy based upon functional alterations that occur earlier than morphologic changes. DCE MRI/CT has also shown the potential of mapping dose responses in normal organs and tissue for evaluation of individual sensitivity to radiation, providing additional opportunities to minimize risks of radiation injury. The evidence for potentially applying DCE MRI and CT for selection and delineation of radiation boost targets is growing. The clinical use of DCE MRI and CT scanning as a biomarker or even a surrogate endpoint for radiation therapy assessment of tumor and normal organs must consider technical validation issues, including standardization, reproducibility, accuracy and robustness, and clinical validation of the sensitivity and specificity for each specific problem of interest. Although holding great promise, to date, DCE MRI and CT scanning have not been qualified as a surrogate endpoint for radiation therapy assessment or for treatment modification in any prospective phase III clinical trial for any tumor site. Copyright © 2011 Elsevier Inc. All rights reserved.

Intrafractional gastric motion and interfractional stomach deformity during radiation therapy.

PubMed

Watanabe, Miho; Isobe, Koichi; Takisima, Haduki; Uno, Takashi; Ueno, Naoyuki; Kawakami, Hiroyuki; Shigematsu, Naoyuki; Yamashita, Miki; Ito, Hisao

2008-06-01

To evaluate intrafractional gastric motion and interfractional variability of the stomach shape during radiation therapy (RT) for gastric lymphoma. For 11 patients with gastric lymphomas, we undertook fluoroscopic examinations at the time of the simulation, and once a week during RT to evaluate inter- and intrafractional gastric variations. We recorded anteroposterior and left to right X-ray images at inhale and exhale in each examination. We gave coordinates based on the bony landmarks in each patient, and identified the most superior, inferior, lateral, ventral, and dorsal points of the stomach on each film. The interfractional motion was assessed as the distance between a point at inhale and the corresponding point at exhale. We also analyzed interfractional variation based on each point measured. The intrafractional gastric motion was 11.7+/-8.3, 11.0+/-7.1, 6.5+/-6.5, 3.4+/-2.3, 7.1+/-8.2, 6.6+/-5.8mm (mean+/-SD) for the superior, inferior, right, left, ventral and dorsal points, respectively, which was significantly different between each point. The interfractional variability of stomach filling was -2.9+/-14.4, -6.0+/-13.4, 9.3+/-22.0mm for the superior-inferior (SI), lateral (LAT), and ventro-dorsal (VD) directions, respectively, and the differences of variabilities were also statistically significant. Thus, the appropriate treatment margins calculated from both systematic and random errors are 30.3, 41.0, and 50.8mm for the SI, LAT, and ventro-dorsal directions, respectively. Both intrafractional gastric motion and interfractional variability of the stomach shape were considerable during RT. We recommend regular verification of gastric movement and shape before and during RT to individualize treatment volume.

Intensity-Modulated Radiation Therapy in Childhood Ependymoma

SciTech Connect

Schroeder, Thomas M.; Chintagumpala, Murali; Okcu, M. Fatih

2008-07-15

Purpose: To determine the patterns of failure after intensity-modulated radiation therapy (IMRT) for localized intracranial ependymoma. Methods and Materials: From 1994 to 2005, 22 children with pathologically proven, localized, intracranial ependymoma were treated with adjuvant IMRT. Of the patients, 12 (55%) had an infratentorial tumor and 14 (64%) had anaplastic histology. Five patients had a subtotal resection (STR), as evidenced by postoperative magnetic resonance imaging. The clinical target volume encompassed the tumor bed and any residual disease plus margin (median dose 54 Gy). Median follow-up for surviving patients was 39.8 months. Results: The 3-year overall survival rate was 87% {+-}more » 9%. The 3-year local control rate was 68% {+-} 12%. There were six local recurrences, all in the high-dose region of the treatment field. Median time to recurrence was 21.7 months. Of the 5 STR patients, 4 experienced recurrence and 3 died. Patients with a gross total resection had significantly better local control (p = 0.024) and overall survival (p = 0.008) than those with an STR. At last follow-up, no patient had developed visual loss, brain necrosis, myelitis, or a second malignancy. Conclusions: Treatment with IMRT provides local control and survival rates comparable with those in historic publications using larger treatment volumes. All failures were within the high-dose region, suggesting that IMRT does not diminish local control. The degree of surgical resection was shown to be significant for local control and survival.« less

Intrafractional baseline drift during free breathing breast cancer radiation therapy.

PubMed

Jensen, Christer Andre; Acosta Roa, Ana María; Lund, Jo-Åsmund; Frengen, Jomar

2017-06-01

Intrafraction motion in breast cancer radiation therapy (BCRT) has not yet been thoroughly described in the literature. It has been observed that baseline drift occurs as part of the intrafraction motion. This study aims to measure baseline drift and its incidence in free-breathing BCRT patients using an in-house developed laser system for tracking the position of the sternum. Baseline drift was monitored in 20 right-sided breast cancer patients receiving free breathing 3D-conformal RT by using an in-house developed laser system which measures one-dimensional distance in the AP direction. A total of 357 patient respiratory traces from treatment sessions were logged and analysed. Baseline drift was compared to patient positioning error measured from in-field portal imaging. The mean overall baseline drift at end of treatment sessions was -1.3 mm for the patient population. Relatively small baseline drift was observed during the first fraction; however it was clearly detected already at the second fraction. Over 90% of the baseline drift occurs during the first 3 min of each treatment session. The baseline drift rate for the population was -0.5 ± 0.2 mm/min in the posterior direction the first minute after localization. Only 4% of the treatment sessions had a 5 mm or larger baseline drift at 5 min, all towards the posterior direction. Mean baseline drift in the posterior direction in free breathing BCRT was observed in 18 of 20 patients over all treatment sessions. This study shows that there is a substantial baseline drift in free breathing BCRT patients. No clear baseline drift was observed during the first treatment session; however, baseline drift was markedly present at the rest of the sessions. Intrafraction motion due to baseline drift should be accounted for in margin calculations.

Intensity Modulated Radiation Therapy With Dose Painting to Treat Rhabdomyosarcoma

SciTech Connect

Yang, Joanna C.; Dharmarajan, Kavita V.; Wexler, Leonard H.

Purpose: To examine local control and patterns of failure in rhabdomyosarcoma patients treated with intensity modulated radiation therapy (RT) with dose painting (DP-IMRT). Patients and Methods: A total of 41 patients underwent DP-IMRT with chemotherapy for definitive treatment. Nineteen also underwent surgery with or without intraoperative RT. Fifty-six percent had alveolar histologic features. The median interval from beginning chemotherapy to RT was 17 weeks (range, 4-25). Very young children who underwent second-look procedures with or without intraoperative RT received reduced doses of 24-36 Gy in 1.4-1.8-Gy fractions. Young adults received 50.4 Gy to the primary tumor and lower doses ofmore » 36 Gy in 1.8-Gy fractions to at-risk lymph node chains. Results: With 22 months of median follow-up, the actuarial local control rate was 90%. Patients aged {<=}7 years who received reduced overall and fractional doses had 100% local control, and young adults had 79% (P=.07) local control. Three local failures were identified in young adults whose primary target volumes had received 50.4 Gy in 1.8-Gy fractions. Conclusions: DP-IMRT with lower fractional and cumulative doses is feasible for very young children after second-look procedures with or without intraoperative RT. DP-IMRT is also feasible in adolescents and young adults with aggressive disease who would benefit from prophylactic RT to high-risk lymph node chains, although dose escalation might be warranted for improved local control. With limited follow-up, it appears that DP-IMRT produces local control rates comparable to those of sequential IMRT in patients with rhabdomyosarcoma.« less

Radiation therapy planning and simulation with magnetic resonance images

NASA Astrophysics Data System (ADS)

Boettger, Thomas; Nyholm, Tufve; Karlsson, Magnus; Nunna, Chandrasekhar; Celi, Juan Carlos

2008-03-01

We present a system which allows for use of magnetic resonance (MR) images as primary RT workflow modality alone and no longer limits the user to computed tomography data for radiation therapy (RT) planning, simulation and patient localization. The single steps for achieving this goal are explained in detail. For planning two MR data sets, MR1 and MR2 are acquired sequentially. For MR1 a standardized Ultrashort TE (UTE) sequence is used enhancing bony anatomy. The sequence for MR2 is chosen to get optimal contrast for the target and the organs at risk for each individual patient. Both images are naturally in registration, neglecting elastic soft tissue deformations. The planning software first automatically extracts skin and bony anatomy from MR1. The user can semi-automatically delineate target structures and organs at risk based on MR1 or MR2, associate all segmentations with MR1 and create a plan in the coordinate system of MR1. Projections similar to digitally reconstructed radiographs (DRR) enhancing bony anatomy are calculated from the MR1 directly and can be used for iso-center definition and setup verification. Furthermore we present a method for creating a Pseudo-CT data set which assigns electron densities to the voxels of MR1 based on the skin and bone segmentations. The Pseudo-CT is then used for dose calculation. Results from first tests under clinical conditions show the feasibility of the completely MR based workflow in RT for necessary clinical cases. It needs to be investigated in how far geometrical distortions influence accuracy of MR-based RT planning.

Reducing operator radiation exposure during cardiac resynchronization therapy.

PubMed

Brambilla, Marco; Occhetta, Eraldo; Ronconi, Martina; Plebani, Laura; Carriero, Alessandro; Marino, Paolo

2010-12-01

To quantify the reduction in equivalent dose at operator's hand that can be achieved by placement of a radiation-absorbing drape (RADPAD) during long-lasting cardiac resynchronization therapy (CRT) procedures. This is a prospective observational study that included 22 consecutive patients with drug-refractory heart failure who underwent implantation of a CRT device. The cases were randomly assigned to Group A (11 cases), performed without RADPAD, and to Group B (11 cases), performed using RADPAD. Dose equivalent at the examiner's hand was measured as H(p)(0.07) and as a time-adjusted H(p)(0.07) rate (mGy/min) with a direct reading dosimeter. The mean fluoroscopy time was 20.8 ± 7.7 min and the mean dose area product (DAP) was 118.6 ± 45.3 Gy cm(2). No significant differences were found between body mass index, fluoroscopy time, and DAP between patients examined with or without RADPAD. The correlation between the fluoroscopy time and the DAP was high (R(2) = 0.94, P < 0.001). Mean dose and dose rate measurement without the RADPAD at the finger and hand were H(p)(0.07) = 1.27 ± 0.47 mGy per procedure and H(p)(0.07) rate = 0.057 ± 0.011 mGy/min, respectively. The dosage was reduced with the RADPAD to H(p)(0.07) = 0.48 ± 0.20 (P < 0.05) and to H(p)(0.07) rate = 0.026 ± 0.008 (P < 0.001), respectively. A mean reduction of 54% in the equivalent dose rate to the operator's hand can be achieved with the use of RADPAD. The use of the RADPAD in CRT devices implantation will make unlikely the necessity of limiting the yearly number of implants for high volume operators.

Daily quality assurance phantom for ultrasound image guided radiation therapy

PubMed Central

Drever, Laura

2007-01-01

A simple phantom was designed, constructed, tested, and clinically implemented for daily quality assurance (QA) of an ultrasound‐image‐guided radiation therapy (US‐IGRT) system, the Restitu Ultrasound system (Resonant Medical, Montreal, QC). The phantom consists of a high signal echogenic background gel surrounding a low signal hypoechoic egg‐shaped target. Daily QA checks involve ultrasound imaging of the phantom and segmenting of the embedded target using the automated tools available on the US‐IGRT system. This process serves to confirm system hardware and software functions and, in particular, accurate determination of the target position. Experiments were conducted to test the stability of the phantom at room temperature, its tissue‐mimicking properties, the reproducibility of target position measurements, and the usefulness of the phantom as a daily QA device. The phantom proved stable at room temperature, exhibited no evidence of bacterial or fungal invasion in 9 months, and showed limited desiccation (resulting in a monthly reduction in ultrasound‐measured volume of approximately 0.2 cm3). Furthermore, the phantom was shown to be nearly tissue‐mimicking, with speed of sound in the phantom estimated to be 0.8% higher than that assumed by the scanner calibration. The phantom performs well in a clinical setting, owing to its light weight and ease of operation. It provides reproducible measures of target position even with multiple users. At our center, the phantom is being used for daily QA of the US‐IGRT system with clinically acceptable tolerances of ±1 cm3 on target volume and ±2 mm on target position. For routine daily QA, this phantom is a good alternative to the manufacturer‐supplied calibration phantom, and we recommended that that larger phantom be reserved for less frequent, more detailed QA checks and system calibration. PACS numbers: 87.66.Xa, 87.63.Df

Multimodality treatment with intensity modulated radiation therapy for esophageal cancer.

PubMed

La, T H; Minn, A Y; Su, Z; Fisher, G A; Ford, J M; Kunz, P; Goodman, K A; Koong, A C; Chang, D T

2010-05-01

The objective of this study is to determine the feasibility and report the outcome of patients with locally advanced esophageal cancer treated with preoperative or definitive chemoradiotherapy (CRT) using intensity-modulated radiation therapy (IMRT). Between 2003 and 2007, 30 patients with non-cervical esophageal cancer received concurrent chemotherapy and IMRT at Stanford University. Eighteen patients were planned for definitive CRT and 12 were planned for preoperative CRT. All patients had computed tomography-based treatment planning and received IMRT. The median dose delivered was 50.4 Gy. Patients planned for preoperative CRT underwent surgery 4-13 weeks (median 8.3 weeks) following completion of CRT. Median follow-up of surviving patients from start of RT was 24.2 months (range 8.2-38.3 months). The majority of tumors were adenocarcinomas (67%) and poorly differentiated (57%). Tumor location was 7% upper, 20% mid, 47% lower, and 27% gastroesophageal junction. Actuarial 2-year local-regional control (LRC) was 64%. High tumor grade was an adverse prognostic factor for LRC and overall survival (OS) (P= 0.015 and 0.012, respectively). The 2-year LRC was 83% vs. 51% for patients treated preoperatively vs. definitively (P= 0.32). The 2-year disease-free and OS were 38% and 56%, respectively. Twelve patients (40%) required feeding tube placement, and the average weight loss from baseline was 4.8%. Twelve (40%) patients experienced grade 3+ acute complications and one patient died of complications following feeding tube placement. Three patients (10%) required a treatment break. Eight patients (27%) experienced grade 3 late complications. No grade 4 complications were seen. IMRT was effective and well tolerated. Disease recurrence remains a challenge and further investigation with dose escalation to improve LRC and OS is warranted.

Intervention quality is not routinely assessed in Cochrane systematic reviews of radiation therapy interventions.

PubMed

Abdul Rahim, Mohamad R; James, Melissa L; Hickey, Brigid E

2017-10-01

The aim of this study was to maximise the benefits from clinical trials involving technological interventions such as radiation therapy. High compliance to the quality assurance protocols is crucial. We assessed whether the quality of radiation therapy intervention was evaluated in Cochrane systematic reviews. We searched 416 published Cochrane systematic reviews and identified 67 Cochrane systematic reviews that investigated radiation therapy or radiotherapy as an intervention. For each systematic review, either quality assurance or quality control for the intervention was identified by a description of such processes in the published systematic reviews. Of the 67 Cochrane systematic reviews studied, only two mentioned quality assurance or quality control. Our findings revealed that 65 of 67 (97%) Cochrane systematic reviews of radiation therapy interventions failed to consider the quality of the intervention. We suggest that advice about the evaluation of intervention quality be added to author support materials. © 2017 The Royal Australian and New Zealand College of Radiologists.

Mesenchymal Stem Cell Therapy for Acute Radiation Syndrome: Innovative Medical Approaches in Military Medicine

DTIC Science & Technology

2015-01-30

mesenchymal stem cells . Cytokine Growth Factor Rev. 2009;20:419–27. 8. Wang L, Li Y, Chen X, Chen J, Gautam SC, Xu Y, et al. MCP...Literature 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Mesenchymal stem cell therapy for acute radiation syndrome: innovative medical...Independent Research Program 14. ABSTRACT See reprint. 15. SUBJECT TERMS Acute radiation syndrome, Mesenchymal stem cell , cell therapy,

Risk of secondary malignancies after radiation therapy for breast cancer: Comprehensive results.

PubMed

Burt, Lindsay M; Ying, Jian; Poppe, Matthew M; Suneja, Gita; Gaffney, David K

2017-10-01

To assess risks of secondary malignancies in breast cancer patients who received radiation therapy compared to patients who did not. The SEER database was used to identify females with a primary diagnosis of breast cancer as their first malignancy, during 1973-2008. We excluded patients with metastatic disease, age <18 years, no definitive surgical intervention, ipsilateral breast cancer recurrence, or who developed a secondary malignancy within 1 year of diagnosis. Standardized incidence ratios and absolute excess risk were calculated using SEER*Stat, version 8.2.1 and SAS, version 9.4. There were 374,993 patients meeting the inclusion criteria, with 154,697 who received radiation therapy. With a median follow-up of 8.9 years, 13% of patients (49,867) developed a secondary malignancy. The rate of secondary malignancies was significantly greater than the endemic rate in breast cancer patients treated without radiation therapy, (O/E 1.2, 95% CI 1.19-1.22) and with radiation therapy (O/E 1.33, 95% CI 1.31-1.35). Approximately 3.4% of secondary malignancies were attributable to radiation therapy. The increased risk of secondary malignancies in breast cancer patients treated with radiation therapy compared to those without was significant regardless of age at breast cancer diagnosis (p < 0.01) and more pronounced with longer latency periods. There was an increased risk of secondary malignancies for breast cancer patients both with and without radiation therapy compared to the general population. There was an increased risk in specific sites for patients treated with radiation therapy. This risk was most evident in young patients and who had longer latency periods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Resectable Pediatric Nonrhabdomyosarcoma Soft Tissue Sarcoma: Which Patients Benefit from Adjuvant Radiation Therapy and How Much?

PubMed Central

Million, Lynn; Donaldson, Sarah S.

2012-01-01

It remains unclear which children and adolescents with resected nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) benefit from radiation therapy, as well as the optimal dose, volume, and timing of radiotherapy when used with primary surgical resection. This paper reviews the sparse literature from clinical trials and retrospective studies of resected pediatric NRSTS to discern local recurrence rates in relationship to the use of radiation therapy. PMID:22523704

Lymphangiosarcoma of the edematous thigh after radiation therapy for carcinoma of the vulva

SciTech Connect

Huey, G.R.; Stehman, F.B.; Roth, L.M.

1985-03-01

A 66-year-old patient was treated with external radiation therapy for an advanced carcinoma of the vulva. Seven years later, a lymphangiosarcoma developed in her edematous lower extremity. Lymphangiosarcomas have been reported to occur in postmastectomy patients; however, this is only the third case in a patient with a gynecologic primary malignancy. In anticipation of possible increased use of radiation therapy in vulvar carcinoma, gynecologists should be aware of this rare, highly aggressive neoplasm.

Effect of single dose radiation therapy on weight-bearing lameness in dogs with elbow osteoarthritis.

PubMed

Kapatkin, Amy S; Nordquist, Barbro; Garcia, Tanya C; Griffin, Maureen A; Theon, Alain; Kim, Sun; Hayashi, Kei

2016-07-19

To determine if a single low dose of radiation therapy in dogs with osteoarthritis of the elbow joint was associated with a detectable improvement in their lameness and pain as documented by force platform gait analysis. In this cohort longitudinal observational study, five Labrador Retrievers with lameness due to elbow osteoarthritis that was unresponsive to medical treatment were removed from all non-steroidal anti-inflammatory and analgesic medications. A single treatment of radiation therapy delivering 10 Gray was performed on the affected elbow joint(s). Force platform gait analysis was used to assess the ground reaction forces of a limb affected with elbow osteoarthritis both before and after radiation therapy. Significant differences occurred in the weight-bearing on an affected limb with elbow osteoarthritis after radiation therapy at weeks six and 14. Change due to treatment was particularly apparent in dogs with unilateral elbow osteoarthritis. Administering a single low dose of radiation therapy may have a short-term benefit in dogs with elbow osteoarthritis, which is similar to the evidence supporting the use of radiation therapy in horses with orthopaedic disease.

Reducing rectal injury in men receiving prostate cancer radiation therapy: current perspectives

PubMed Central

Serrano, Nicholas A; Kalman, Noah S; Anscher, Mitchell S

2017-01-01

Dose escalation is now the standard of care for the treatment of prostate cancer with radiation therapy. However, the rectum tends to be the dose-limiting structure when treating prostate cancer, given its close proximity. Early and late toxicities can occur when the rectum receives large doses of radiation therapy. New technologies allow for prevention of these toxicities. In this review, we examine the evidence that supports various dose constraints employed to prevent these rectal injuries from occurring. We also examine the use of intensity-modulated radiation therapy and how this compares to older radiation therapy techniques that allow for further sparing of the rectum during a radiation therapy course. We then review the literature on endorectal balloons and the effects of their daily use throughout a radiation therapy course. Tissue spacers are now being investigated in greater detail; these devices are injected into the rectoprostatic fascia to physically increase the distance between the prostate and the anterior rectal wall. Last, we review the use of systemic drugs, specifically statin medications and antihypertensives, as well as their impact on rectal toxicity. PMID:28814898

TH-F-202-03: Advances in MRI for Radiation Therapy

SciTech Connect

Cai, J.

MRI has excellent soft tissue contrast and can provide both anatomical and physiological information. It is becoming increasingly important in radiation therapy for treatment planning, image-guided radiation therapy, and treatment assessment. It is critically important at this time point to educate and update our medical physicists about MRI to prepare for the upcoming surge of MRI applications in radiation therapy. This session will review important basics of MR physics, pulse sequence designs, and current radiotherapy application, as well as showcase exciting new developments in MRI that can be potentially useful in radiation therapy. Learning Objectives: To learn basics of MRmore » physics and understand the differences between various pulse sequences To review current applications of MRI in radiation therapy.To discuss recent MRI advances for future MRI guided radiation therapy Partly supported by NIH (1R21CA165384).; W. Miller, Research supported in part by Siemens Healthcare; G. Li, My clinical research is in part supported by NIH U54CA137788. I have a collaborative research project with Philips Healthcare.; J. Cai, jing cai.« less

Ceiling art in a radiation therapy department: its effect on patient treatment experience

SciTech Connect

Bonett, Jotham

A new initiative has been implemented at the Sunshine Hospital Radiation Therapy Centre, to provide a calming and comforting environment for patients attending radiation therapy treatment. As part of this initiative, the department's computed tomography (CT) room and radiation therapy bunkers were designed to incorporate ceiling art that replicates a number of different visual scenes. The study was undertaken to determine if ceiling art in the radiation therapy treatment CT and treatment bunkers had an effect on a patient's experience during treatment at the department. Additionally, the study aimed to identify which of the visuals in the ceiling art weremore » most preferred by patients. Patients were requested to complete a 12-question survey. The survey solicited a patient's opinion/perception on the unit's unique ceiling display with emphasis on aesthetic appeal, patient treatment experience and the patient's engagement due to the ceiling display. The responses were dichotomised to ‘positive’ or ‘negative’. Every sixth patient who completed the survey was invited to have a general face-to-face discussion to provide further information about their thoughts on the displays. The results demonstrate that the ceiling artwork solicited a positive reaction in 89.8% of patients surveyed. This score indicates that ceiling artwork contributed positively to patients’ experiences during radiation therapy treatment. The study suggests that ceiling artwork in the department has a positive effect on patient experience during their radiation therapy treatment at the department.« less

Improving Quality and Access to Radiation Therapy-An IAEA Perspective.

PubMed

Abdel-Wahab, May; Zubizarreta, Eduardo; Polo, Alfredo; Meghzifene, Ahmed

2017-04-01

The International Atomic Energy Agency (IAEA) has been involved in radiation therapy since soon after its creation in 1957. In response to the demands of Member States, the IAEA׳s activities relating to radiation therapy have focused on supporting low- and middle-income countries to set up radiation therapy facilities, expand the scope of treatments, or gradually transition to new technologies. In addition, the IAEA has been very active in providing internationally harmonized guidelines on clinical, dosimetry, medical physics, and safety aspects of radiation therapy. IAEA clinical research has provided evidence for treatment improvement as well as highly effective resource-sparing interventions. In the process, training of researchers occurs through this program. To provide this support, the IAEA works with its Member States and multiple partners worldwide through several mechanisms. In this article, we review the main activities conducted by the IAEA in support to radiation therapy. IAEA support has been crucial for achieving tangible results in many low- and middle-income countries. However, long-term sustainability of projects can present a challenge, especially when considering health budget constraints and the brain drain of skilled professionals. The need for support remains, with more than 90% of patients in low-income countries lacking access to radiotherapy. Thus, the IAEA is expected to continue its support and strengthen quality radiation therapy treatment of patients with cancer. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

EGFR Targeted Therapies and Radiation: Optimizing Efficacy by Appropriate Drug Scheduling and Patient Selection

PubMed Central

Cuneo, Kyle C.; Nyati, Mukesh K.; Ray, Dipankar; Lawrence, Theodore S.

2015-01-01

The epidermal growth factor receptor (EGFR) plays an important role in tumor progression and treatment resistance for many types of malignancies including head and neck, colorectal, and nonsmall cell lung cancer. Several EGFR targeted therapies are efficacious as single agents or in combination with chemotherapy. Given the toxicity associated with chemoradiation and poor outcomes seen in several types of cancers, combinations of EGFR targeted agents with or without chemotherapy have been tested in patients receiving radiation. To date, the only FDA approved use of an anti-EGFR therapy in combination with radiation therapy is for locally advanced head and neck cancer. Given the important role EGFR plays in lung and colorectal cancer and the benefit of EGFR inhibition combined with chemotherapy in these disease sites, it is perplexing why EGFR targeted therapies in combination with radiation or chemoradiation have not been more successful. In this review we summarize the clinical findings of EGFR targeted therapies combined with radiation and chemoradiation regimens. We then discuss the interaction between EGFR and radiation including radiation induced EGFR signaling, the effect of EGFR on DNA damage repair, and potential mechanisms of radiosensitization. Finally, we examine the potential pitfalls with scheduling EGFR targeted therapies with chemoradiation and the use of predictive biomarkers to improve patient selection. PMID:26205191

Comfort and quality of life in patients with breast cancer undergoing radiation therapy.

PubMed

Pehlivan, Seda; Kuzhan, Abdurrahman; Yildirim, Yasemin; Fadiloglu, Cicek

2016-01-01

Radiation therapy is generally applied after surgery for the treatment of breast cancer, which is among the most frequently observed types of cancer in females. Radiation therapy may have some negative effects on the quality of life due to various side effects such as changes in the skin, mucositis and fatigue. Our study was planned as a descriptive study, in order to examine the relationship between comfort and quality of life in breast cancer patients undergoing radiation therapy. This study involved 61 patients with breast cancer undergoing radiation therapy. Data were collected using "Patient Information Form", "Radiation Therapy Comfort Questionnaire" and "EORTC QLQ-BR23". The scales were applied twice, before the start and at the end of treatment. Data were evaluated via Wilcoxon test and Spearman correlation analyses. No statistically significant difference was determined between comfort and quality of life average score before and after radiotherapy (p>0.05). A positive relationship was determined between the pain and symptom quality of life (p<0.05). Although a positive relationship was determined between comfort score and the functional and general quality of life areas, a negative relationship was detected with the symptom quality of life (p<0.01). Radiation therapy applied to breast cancer patients did not affect comfort and quality of life, On the contrary, the quality of life of patients increased along with their comfort levels and that comfort levels decreased as the experienced symptoms increased.

Radiation or chemoradiation: initial utility study of selected therapy for local advanced stadium cervical cancer

NASA Astrophysics Data System (ADS)

Pramitasari, D. A.; Gondhowiardjo, S.; Nuranna, L.

2017-08-01

This study aimed to compare radiation only or chemo radiation treatment of local advanced cervical cancers by examining the initial response of tumors and acute side effects. An initial assessment employed value based medicine (VBM) by obtaining utility values for both types of therapy. The incidences of acute lower gastrointestinal, genitourinary, and hematology side effects in patients undergoing chemoradiation did not differ significantly from those undergoing radiation alone. Utility values for patients who underwent radiation alone were higher compared to those who underwent chemoradiation. It was concluded that the complete response of patients who underwent chemoradiation did not differ significantly from those who underwent radiation alone.

Prevalence of complementary and alternative therapy use by cancer patients undergoing radiation therapy.

PubMed

Edwards, Grace V; Aherne, Noel J; Horsley, Patrick J; Benjamin, Linus C; McLachlan, Craig S; McKay, Michael J; Shakespeare, Thomas P

2014-12-01

The use of complementary and alternative therapies (CAT) in oncology patients is increasing in incidence, with calls to routinely screen for their use. We introduced a screening tool as part of clinical care to identify CAT use. We evaluated all patients who attended the radiation oncology outpatient clinic between December 2011 and July 2012, who had filled out the CAT screening tool, and evaluated types of CAT use, reasons for use and predictors of CAT usage. A total of 639 patients completed the CAT screening tool, which was 75% of eligible patients. There were 464 (72.6%) men and 175 (27.4%) women, with a mean age of 69.9 years (range 27-94 years). Prostate cancer was the predominant diagnosis (53.1%), followed by breast cancer (17.5%) and skin cancer (14.7%). Of these, 530 patients (82.9%) had used at least one therapy. Of the 530 patients using CAT, the most quoted reasons for use were to improve quality of life (42.6%), to boost the immune system and general health (33.6%), to increase energy levels (32.6%) and to live longer (28.9%). Of the 530 users, only 112 patients (21.1%) took CAT to help cure their cancer. Women were significantly more likely to use CAT, as were patients with breast cancer. The use of CAT in patients with cancer is prevalent and more frequent in our population than in other published studies. Few patients use CAT to improve their cancer cure, but rather use CAT for other reasons. © 2014 Wiley Publishing Asia Pty Ltd.

Appetite and adverse effects associated with radiation therapy in patients with head and neck cancer.

PubMed

Ogama, Norimasa; Suzuki, Sumie; Umeshita, Koji; Kobayashi, Tamami; Kaneko, Shoko; Kato, Sakiko; Shimizu, Yasuko

2010-02-01

The relationship between radiation treatment and adverse effects resulting in changes in appetite was studied in patients with head and neck (H&N) cancer. Path analysis was used to evaluate the following factors in 117 patients receiving radiation therapy for H&N cancer: daily fluctuations in saliva production, analgesic use, frequency of oral care, subject characteristics, and appetite. At 20 Gy of radiation, appetite was affected by Brinkman index value, age, and sensitivity to taste (R2=0.48, p<0.001); at 30 Gy of radiation, appetite was affected by frequency of oral care, xerostomia symptoms, age, sensitivity to taste, and oral mucositis (R2=0.52, p<0.001); and at 50 Gy of radiation, appetite was affected by low saliva production in the morning, frequency of oral care, xerostomia symptoms, sensitivity to taste, analgesic use, and oral mucositis (R2=0.62, p<0.001). The results of this study suggest that care taken to avoid a decrease in appetite due to adverse effects of radiation therapy should differ according to the dosage and schedule of radiation therapy. These findings represent important data for health care professionals to understand and support appropriate dietary intake and improved quality of life for H&N cancer patients receiving radiation therapy. Copyright 2009 Elsevier Ltd. All rights reserved.

Tooth extraction by orthodontic force after radiation therapy: report of case

SciTech Connect

Rodu, B.; Filler, S.J.; Woodfin, G.K.

1985-12-01

This report presents a therapeutic approach to orthodontic tooth extraction in a patient at high risk for the development of osteoradionecrosis with conventional techniques. The rationale for this procedure is discussed in detail, combining principles of radiation biology, clinical radiation therapy, and biomechanics of tooth movement.

Synovial sarcoma of the neck associated with previous head and neck radiation therapy

SciTech Connect

Mischler, N.E.; Chuprevich, T.; Tormey, D.C.

1978-08-01

Synovial sarcoma is a rare neoplasm that uncommonly arises in the neck. Fourteen years after facial and neck radiation therapy for acne, synovial sarcoma of the neck developed in a young man. Possible radiation-induced benign and malignant neoplasms that arise in the head and neck region, either of thyroid or extrathyroid origin, remain a continuing medical problem.

21 CFR 892.5770 - Powered radiation therapy patient support assembly.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Powered radiation therapy patient support assembly. 892.5770 Section 892.5770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5770 Powered radiation...

Differentiation of deep venous thrombosis from femoral vein mixing artifact on routine abdominopelvic CT.

PubMed

Doshi, Ankur M; Hoffman, David; Kierans, Andrea S; Ream, Justin M; Rosenkrantz, Andrew B

2015-10-01

The objective of this study is to assess the performance of qualitative and quantitative imaging features for the differentiation of deep venous thrombosis (DVT) from mixing artifact on routine portal venous phase abdominopelvic CT. This retrospective study included 40 adult patients with a femoral vein filling defect on portal venous phase CT and a Duplex ultrasound (n = 36) or catheter venogram (n = 4) to confirm presence or absence of DVT. Two radiologists (R1, R2) assessed the femoral veins for various qualitative and quantitative features. 60% of patients were confirmed to have DVT and 40% had mixing artifact. Features with significantly greater frequency in DVT than mixing artifact (all p ≤ 0.006) were central location (R1 90% vs. 28%; R2 96% vs. 31%), sharp margin (R1 83% vs. 28%; R2 96% vs. 31%), venous expansion (R1 48% vs. 6%, R2 56% vs. 6%), and venous wall enhancement (R1 62% vs. 0%; R2 48% vs. 0%). DVT exhibited significantly lower mean attenuation than mixing artifact (R1 42.1 ± 20.2 vs. 57.1 ± 23.6 HU; R2 43.6 ± 19.4 vs. 58.8 ± 23.4 HU, p ≤ 0.031) and a significantly larger difference in vein diameter compared to the contralateral vein (R1 0.4 ± 0.4 vs. 0.1 ± 0.2 cm; R2 0.3 ± 0.4 vs. 0.0 ± 0.1 cm, p ≤ 0.026). At multivariable analysis, central location and sharp margin were significant independent predictors of DVT for both readers (p ≤ 0.013). Awareness of these qualitative and quantitative imaging features may improve radiologists' confidence for differentiating femoral vein DVT and mixing artifact on routine portal venous phase CT. However, given overlap with mixing artifact, larger studies remain warranted.

Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy

NASA Astrophysics Data System (ADS)

Hälg, R. A.; Besserer, J.; Boschung, M.; Mayer, S.; Lomax, A. J.; Schneider, U.

2014-05-01

In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important. This study quantified the neutron doses for different radiation therapy modalities. Most of the reports in the literature used neutron dose measurements free in air or on the surface of phantoms to estimate the amount of neutron dose to the patient. In this study, dose measurements were performed in terms of neutron dose equivalent inside an anthropomorphic phantom. The neutron dose equivalent was determined using track etch detectors as a function of the distance to the isocenter, as well as for radiation sensitive organs. The dose distributions were compared with respect to treatment techniques (3D-conformal, volumetric modulated arc therapy and intensity-modulated radiation therapy for photons; spot scanning and passive scattering for protons), therapy machines (Varian, Elekta and Siemens linear accelerators) and radiation quality (photons and protons). The neutron dose equivalent varied between 0.002 and 3 mSv per treatment gray over all measurements. Only small differences were found when comparing treatment techniques, but substantial differences were observed between the linear accelerator models. The neutron dose equivalent for proton therapy was higher than for photons in general and in particular for double-scattered protons. The overall neutron dose equivalent measured in this study was an order of magnitude lower than the stray dose of a treatment using 6 MV photons, suggesting that the contribution of the secondary neutron dose equivalent to the integral dose of a radiotherapy patient is small.

Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy.

PubMed

Hälg, R A; Besserer, J; Boschung, M; Mayer, S; Lomax, A J; Schneider, U

2014-05-21

In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important. This study quantified the neutron doses for different radiation therapy modalities. Most of the reports in the literature used neutron dose measurements free in air or on the surface of phantoms to estimate the amount of neutron dose to the patient. In this study, dose measurements were performed in terms of neutron dose equivalent inside an anthropomorphic phantom. The neutron dose equivalent was determined using track etch detectors as a function of the distance to the isocenter, as well as for radiation sensitive organs. The dose distributions were compared with respect to treatment techniques (3D-conformal, volumetric modulated arc therapy and intensity-modulated radiation therapy for photons; spot scanning and passive scattering for protons), therapy machines (Varian, Elekta and Siemens linear accelerators) and radiation quality (photons and protons). The neutron dose equivalent varied between 0.002 and 3 mSv per treatment gray over all measurements. Only small differences were found when comparing treatment techniques, but substantial differences were observed between the linear accelerator models. The neutron dose equivalent for proton therapy was higher than for photons in general and in particular for double-scattered protons. The overall neutron dose equivalent measured in this study was an order of magnitude lower than the stray dose of a treatment using 6 MV photons, suggesting that the contribution of the secondary neutron dose equivalent to the integral dose of a radiotherapy patient is small.

Tobacco Smoking During Radiation Therapy for Head-and-Neck Cancer Is Associated With Unfavorable Outcome

SciTech Connect

Chen, Allen M., E-mail: allen.chen@ucdmc.ucdavis.ed; Chen, Leon M.; Vaughan, Andrew

Purpose: To evaluate the effect of continued cigarette smoking among patients undergoing radiation therapy for head-and-neck cancer by comparing the clinical outcomes among active smokers and quitters. Methods and Materials: A review of medical records identified 101 patients with newly diagnosed squamous cell carcinoma of the head and neck who continued to smoke during radiation therapy. Each active smoker was matched to a control patient who had quit smoking before initiation of radiation therapy. Matching was based on tobacco history (pack-years), primary site, age, sex, Karnofsky Performance Status, disease stage, radiation dose, chemotherapy use, year of treatment, and whether surgicalmore » resection was performed. Outcomes were compared by use of Kaplan-Meier analysis. Normal tissue effects were graded according to the Radiation Therapy Oncology Group/European Organization for the Treatment of Cancer toxicity criteria. Results: With a median follow-up of 49 months, active smokers had significantly inferior 5-year overall survival (23% vs. 55%), locoregional control (58% vs. 69%), and disease-free survival (42% vs. 65%) compared with the former smokers who had quit before radiation therapy (p < 0.05 for all). These differences remained statistically significant when patients treated by postoperative or definitive radiation therapy were analyzed separately. The incidence of Grade 3 or greater late complications was also significantly increased among active smokers compared with former smokers (49% vs. 31%, p = 0.01). Conclusions: Tobacco smoking during radiation therapy for head-and-neck cancer is associated with unfavorable outcomes. Further studies analyzing the biologic and molecular reasons underlying these differences are planned.« less

[The Learning Effectiveness of Nurses Participating in a Simulated Radiation Therapy Skin Care Workshop].

PubMed

Lee, Yu-San; Kao, Yu-Hsiu

2016-08-01

The skin reaction rate is 60-95% in cancer patients that receive radiation therapy. This therapy is likely to cause physical and mental discomfort and prolong treatment for patients. The current emphasis on lectures rather than practice to help nurses learn proper skin care practices likely imposes difficulties for nurses to handle various clinical situations. To investigate the learning effectiveness of a simulated radiation therapy skin care workshop for nurses. A total of 34 nurses at a hospital in one health system in northern Taiwan who had never used radiation therapy to provide care to patients were enrolled in this quasi-experimental study. A single group pretest, posttest and post-posttest (6 weeks after intervention) approach was used. At the simulated radiation therapy skin care workshop, we used teaching strategies including Ausubel's direct instruction teaching method and practice on simulated wounds on pig skins. Outcomes were evaluated using "the questionnaire of radiation therapy skin care" and "direct observation of procedural skills checklist". The results from the simulated radiation therapy skin care workshop were analyzed using GEE (generalized estimating equation). The post-posttest and posttest scores increased significantly; knowledge mean score 3.14 (< .001) vs 2.64 (< .001), attitude mean score 2.06 (p < .05) vs 2.24 (p < .001), and skill mean score 2.79 (p < .001) vs 1.68 (p < .001). The simulated radiation therapy skin care workshop demonstrated significant and positive effects on learning outcomes. Therefore, we recommend incorporating this workshop into clinical nursing education and training strategies in the future.

Redox-Modulated Phenomena and Radiation Therapy: The Central Role of Superoxide Dismutases

PubMed Central

Holley, Aaron K.; Miao, Lu; St. Clair, Daret K.

2014-01-01

Abstract Significance: Ionizing radiation is a vital component in the oncologist's arsenal for the treatment of cancer. Approximately 50% of all cancer patients will receive some form of radiation therapy as part of their treatment regimen. DNA is considered the major cellular target of ionizing radiation and can be damaged directly by radiation or indirectly through reactive oxygen species (ROS) formed from the radiolysis of water, enzyme-mediated ROS production, and ROS resulting from altered aerobic metabolism. Recent Advances: ROS are produced as a byproduct of oxygen metabolism, and superoxide dismutases (SODs) are the chief scavengers. ROS contribute to the radioresponsiveness of normal and tumor tissues, and SODs modulate the radioresponsiveness of tissues, thus affecting the efficacy of radiotherapy. Critical Issues: Despite its prevalent use, radiation therapy suffers from certain limitations that diminish its effectiveness, including tumor hypoxia and normal tissue damage. Oxygen is important for the stabilization of radiation-induced DNA damage, and tumor hypoxia dramatically decreases radiation efficacy. Therefore, auxiliary therapies are needed to increase the effectiveness of radiation therapy against tumor tissues while minimizing normal tissue injury. Future Directions: Because of the importance of ROS in the response of normal and cancer tissues to ionizing radiation, methods that differentially modulate the ROS scavenging ability of cells may prove to be an important method to increase the radiation response in cancer tissues and simultaneously mitigate the damaging effects of ionizing radiation on normal tissues. Altering the expression or activity of SODs may prove valuable in maximizing the overall effectiveness of ionizing radiation. Antioxid. Redox Signal. 20, 1567–1589. PMID:24094070

Metalloporphyrins and their uses as radiosensitizers for radiation therapy

DOEpatents

Miura, Michiko; Slatkin, Daniel N.

2004-07-06

The present invention covers radiosensitizers containing as an active ingredient halogenated derivatives of boronated porphyrins containing multiple carborane cages having the structure ##STR1## which selectively accumulate in neoplastic tissue within the irradiation volume and thus can be used in cancer therapies including, but not limited to, boron neutron--capture therapy and photodynamic therapy. The present invention also covers methods for using these radiosensitizers in tumor imaging and cancer treatment.

A computer aided treatment event recognition system in radiation therapy.

PubMed

Xia, Junyi; Mart, Christopher; Bayouth, John

2014-01-01

To develop an automated system to safeguard radiation therapy treatments by analyzing electronic treatment records and reporting treatment events. CATERS (Computer Aided Treatment Event Recognition System) was developed to detect treatment events by retrieving and analyzing electronic treatment records. CATERS is designed to make the treatment monitoring process more efficient by automating the search of the electronic record for possible deviations from physician's intention, such as logical inconsistencies as well as aberrant treatment parameters (e.g., beam energy, dose, table position, prescription change, treatment overrides, etc). Over a 5 month period (July 2012-November 2012), physicists were assisted by the CATERS software in conducting normal weekly chart checks with the aims of (a) determining the relative frequency of particular events in the authors' clinic and (b) incorporating these checks into the CATERS. During this study period, 491 patients were treated at the University of Iowa Hospitals and Clinics for a total of 7692 fractions. All treatment records from the 5 month analysis period were evaluated using all the checks incorporated into CATERS after the training period. About 553 events were detected as being exceptions, although none of them had significant dosimetric impact on patient treatments. These events included every known event type that was discovered during the trial period. A frequency analysis of the events showed that the top three types of detected events were couch position override (3.2%), extra cone beam imaging (1.85%), and significant couch position deviation (1.31%). The significant couch deviation is defined as the number of treatments where couch vertical exceeded two times standard deviation of all couch verticals, or couch lateral/longitudinal exceeded three times standard deviation of all couch laterals and longitudinals. On average, the application takes about 1 s per patient when executed on either a desktop computer

The Advantages of Collimator Optimization for Intensity Modulated Radiation Therapy

NASA Astrophysics Data System (ADS)

Doozan, Brian

The goal of this study was to improve dosimetry for pelvic, lung, head and neck, and other cancers sites with aspherical planning target volumes (PTV) using a new algorithm for collimator optimization for intensity modulated radiation therapy (IMRT) that minimizes the x-jaw gap (CAX) and the area of the jaws (CAA) for each treatment field. A retroactive study on the effects of collimator optimization of 20 patients was performed by comparing metric results for new collimator optimization techniques in Eclipse version 11.0. Keeping all other parameters equal, multiple plans are created using four collimator techniques: CA 0, all fields have collimators set to 0°, CAE, using the Eclipse collimator optimization, CAA, minimizing the area of the jaws around the PTV, and CAX, minimizing the x-jaw gap. The minimum area and the minimum x-jaw angles are found by evaluating each field beam's eye view of the PTV with ImageJ and finding the desired parameters with a custom script. The evaluation of the plans included the monitor units (MU), the maximum dose of the plan, the maximum dose to organs at risk (OAR), the conformity index (CI) and the number of fields that are calculated to split. Compared to the CA0 plans, the monitor units decreased on average by 6% for the CAX method with a p-value of 0.01 from an ANOVA test. The average maximum dose remained within 1.1% difference between all four methods with the lowest given by CAX. The maximum dose to the most at risk organ was best spared by the CAA method, which decreased by 0.62% compared to the CA0. Minimizing the x-jaws significantly reduced the number of split fields from 61 to 37. In every metric tested the CAX optimization produced comparable or superior results compared to the other three techniques. For aspherical PTVs, CAX on average reduced the number of split fields, lowered the maximum dose, minimized the dose to the surrounding OAR, and decreased the monitor units. This is achieved while maintaining the same

Optimizing global liver function in radiation therapy treatment planning

NASA Astrophysics Data System (ADS)

Wu, Victor W.; Epelman, Marina A.; Wang, Hesheng; Romeijn, H. Edwin; Feng, Mary; Cao, Yue; Ten Haken, Randall K.; Matuszak, Martha M.

2016-09-01

Liver stereotactic body radiation therapy (SBRT) patients differ in both pre-treatment liver function (e.g. due to degree of cirrhosis and/or prior treatment) and radiosensitivity, leading to high variability in potential liver toxicity with similar doses. This work investigates three treatment planning optimization models that minimize risk of toxicity: two consider both voxel-based pre-treatment liver function and local-function-based radiosensitivity with dose; one considers only dose. Each model optimizes different objective functions (varying in complexity of capturing the influence of dose on liver function) subject to the same dose constraints and are tested on 2D synthesized and 3D clinical cases. The normal-liver-based objective functions are the linearized equivalent uniform dose (\\ell \\text{EUD} ) (conventional ‘\\ell \\text{EUD} model’), the so-called perfusion-weighted \\ell \\text{EUD} (\\text{fEUD} ) (proposed ‘fEUD model’), and post-treatment global liver function (GLF) (proposed ‘GLF model’), predicted by a new liver-perfusion-based dose-response model. The resulting \\ell \\text{EUD} , fEUD, and GLF plans delivering the same target \\ell \\text{EUD} are compared with respect to their post-treatment function and various dose-based metrics. Voxel-based portal venous liver perfusion, used as a measure of local function, is computed using DCE-MRI. In cases used in our experiments, the GLF plan preserves up to 4.6 % ≤ft(7.5 % \\right) more liver function than the fEUD (\\ell \\text{EUD} ) plan does in 2D cases, and up to 4.5 % ≤ft(5.6 % \\right) in 3D cases. The GLF and fEUD plans worsen in \\ell \\text{EUD} of functional liver on average by 1.0 Gy and 0.5 Gy in 2D and 3D cases, respectively. Liver perfusion information can be used during treatment planning to minimize the risk of toxicity by improving expected GLF; the degree of benefit varies with perfusion pattern. Although fEUD model optimization is computationally inexpensive and

Optimization of rotational arc station parameter optimized radiation therapy.

PubMed

Dong, P; Ungun, B; Boyd, S; Xing, L

2016-09-01

To develop a fast optimization method for station parameter optimized radiation therapy (SPORT) and show that SPORT is capable of matching VMAT in both plan quality and delivery efficiency by using three clinical cases of different disease sites. The angular space from 0° to 360° was divided into 180 station points (SPs). A candidate aperture was assigned to each of the SPs based on the calculation results using a column generation algorithm. The weights of the apertures were then obtained by optimizing the objective function using a state-of-the-art GPU based proximal operator graph solver. To avoid being trapped in a local minimum in beamlet-based aperture selection using the gradient descent algorithm, a stochastic gradient descent was employed here. Apertures with zero or low weight were thrown out. To find out whether there was room to further improve the plan by adding more apertures or SPs, the authors repeated the above procedure with consideration of the existing dose distribution from the last iteration. At the end of the second iteration, the weights of all the apertures were reoptimized, including those of the first iteration. The above procedure was repeated until the plan could not be improved any further. The optimization technique was assessed by using three clinical cases (prostate, head and neck, and brain) with the results compared to that obtained using conventional VMAT in terms of dosimetric properties, treatment time, and total MU. Marked dosimetric quality improvement was demonstrated in the SPORT plans for all three studied cases. For the prostate case, the volume of the 50% prescription dose was decreased by 22% for the rectum and 6% for the bladder. For the head and neck case, SPORT improved the mean dose for the left and right parotids by 15% each. The maximum dose was lowered from 72.7 to 71.7 Gy for the mandible, and from 30.7 to 27.3 Gy for the spinal cord. The mean dose for the pharynx and larynx was reduced by 8% and 6

Optimization of rotational arc station parameter optimized radiation therapy

PubMed Central

Dong, P.; Ungun, B.; Boyd, S.; Xing, L.

2016-01-01

Purpose: To develop a fast optimization method for station parameter optimized radiation therapy (SPORT) and show that SPORT is capable of matching VMAT in both plan quality and delivery efficiency by using three clinical cases of different disease sites. Methods: The angular space from 0° to 360° was divided into 180 station points (SPs). A candidate aperture was assigned to each of the SPs based on the calculation results using a column generation algorithm. The weights of the apertures were then obtained by optimizing the objective function using a state-of-the-art GPU based proximal operator graph solver. To avoid being trapped in a local minimum in beamlet-based aperture selection using the gradient descent algorithm, a stochastic gradient descent was employed here. Apertures with zero or low weight were thrown out. To find out whether there was room to further improve the plan by adding more apertures or SPs, the authors repeated the above procedure with consideration of the existing dose distribution from the last iteration. At the end of the second iteration, the weights of all the apertures were reoptimized, including those of the first iteration. The above procedure was repeated until the plan could not be improved any further. The optimization technique was assessed by using three clinical cases (prostate, head and neck, and brain) with the results compared to that obtained using conventional VMAT in terms of dosimetric properties, treatment time, and total MU. Results: Marked dosimetric quality improvement was demonstrated in the SPORT plans for all three studied cases. For the prostate case, the volume of the 50% prescription dose was decreased by 22% for the rectum and 6% for the bladder. For the head and neck case, SPORT improved the mean dose for the left and right parotids by 15% each. The maximum dose was lowered from 72.7 to 71.7 Gy for the mandible, and from 30.7 to 27.3 Gy for the spinal cord. The mean dose for the pharynx and larynx was

Couch height–based patient setup for abdominal radiation therapy

SciTech Connect

Ohira, Shingo; Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita; Ueda, Yoshihiro

2016-04-01

There are 2 methods commonly used for patient positioning in the anterior-posterior (A-P) direction: one is the skin mark patient setup method (SMPS) and the other is the couch height–based patient setup method (CHPS). This study compared the setup accuracy of these 2 methods for abdominal radiation therapy. The enrollment for this study comprised 23 patients with pancreatic cancer. For treatments (539 sessions), patients were set up by using isocenter skin marks and thereafter treatment couch was shifted so that the distance between the isocenter and the upper side of the treatment couch was equal to that indicated on themore » computed tomographic (CT) image. Setup deviation in the A-P direction for CHPS was measured by matching the spine of the digitally reconstructed radiograph (DRR) of a lateral beam at simulation with that of the corresponding time-integrated electronic portal image. For SMPS with no correction (SMPS/NC), setup deviation was calculated based on the couch-level difference between SMPS and CHPS. SMPS/NC was corrected using 2 off-line correction protocols: no action level (SMPS/NAL) and extended NAL (SMPS/eNAL) protocols. Margins to compensate for deviations were calculated using the Stroom formula. A-P deviation > 5 mm was observed in 17% of SMPS/NC, 4% of SMPS/NAL, and 4% of SMPS/eNAL sessions but only in one CHPS session. For SMPS/NC, 7 patients (30%) showed deviations at an increasing rate of > 0.1 mm/fraction, but for CHPS, no such trend was observed. The standard deviations (SDs) of systematic error (Σ) were 2.6, 1.4, 0.6, and 0.8 mm and the root mean squares of random error (σ) were 2.1, 2.6, 2.7, and 0.9 mm for SMPS/NC, SMPS/NAL, SMPS/eNAL, and CHPS, respectively. Margins to compensate for the deviations were wide for SMPS/NC (6.7 mm), smaller for SMPS/NAL (4.6 mm) and SMPS/eNAL (3.1 mm), and smallest for CHPS (2.2 mm). Achieving better setup with smaller margins, CHPS appears to be a reproducible method for abdominal patient setup.« less

Optimization of rotational arc station parameter optimized radiation therapy

SciTech Connect

Dong, P.; Ungun, B.

Purpose: To develop a fast optimization method for station parameter optimized radiation therapy (SPORT) and show that SPORT is capable of matching VMAT in both plan quality and delivery efficiency by using three clinical cases of different disease sites. Methods: The angular space from 0° to 360° was divided into 180 station points (SPs). A candidate aperture was assigned to each of the SPs based on the calculation results using a column generation algorithm. The weights of the apertures were then obtained by optimizing the objective function using a state-of-the-art GPU based proximal operator graph solver. To avoid being trappedmore » in a local minimum in beamlet-based aperture selection using the gradient descent algorithm, a stochastic gradient descent was employed here. Apertures with zero or low weight were thrown out. To find out whether there was room to further improve the plan by adding more apertures or SPs, the authors repeated the above procedure with consideration of the existing dose distribution from the last iteration. At the end of the second iteration, the weights of all the apertures were reoptimized, including those of the first iteration. The above procedure was repeated until the plan could not be improved any further. The optimization technique was assessed by using three clinical cases (prostate, head and neck, and brain) with the results compared to that obtained using conventional VMAT in terms of dosimetric properties, treatment time, and total MU. Results: Marked dosimetric quality improvement was demonstrated in the SPORT plans for all three studied cases. For the prostate case, the volume of the 50% prescription dose was decreased by 22% for the rectum and 6% for the bladder. For the head and neck case, SPORT improved the mean dose for the left and right parotids by 15% each. The maximum dose was lowered from 72.7 to 71.7 Gy for the mandible, and from 30.7 to 27.3 Gy for the spinal cord. The mean dose for the pharynx and larynx

Technological Advancements and Error Rates in Radiation Therapy Delivery

SciTech Connect

Margalit, Danielle N., E-mail: dmargalit@partners.org; Harvard Cancer Consortium and Brigham and Women's Hospital/Dana Farber Cancer Institute, Boston, MA; Chen, Yu-Hui

2011-11-15

Purpose: Technological advances in radiation therapy (RT) delivery have the potential to reduce errors via increased automation and built-in quality assurance (QA) safeguards, yet may also introduce new types of errors. Intensity-modulated RT (IMRT) is an increasingly used technology that is more technically complex than three-dimensional (3D)-conformal RT and conventional RT. We determined the rate of reported errors in RT delivery among IMRT and 3D/conventional RT treatments and characterized the errors associated with the respective techniques to improve existing QA processes. Methods and Materials: All errors in external beam RT delivery were prospectively recorded via a nonpunitive error-reporting system atmore » Brigham and Women's Hospital/Dana Farber Cancer Institute. Errors are defined as any unplanned deviation from the intended RT treatment and are reviewed during monthly departmental quality improvement meetings. We analyzed all reported errors since the routine use of IMRT in our department, from January 2004 to July 2009. Fisher's exact test was used to determine the association between treatment technique (IMRT vs. 3D/conventional) and specific error types. Effect estimates were computed using logistic regression. Results: There were 155 errors in RT delivery among 241,546 fractions (0.06%), and none were clinically significant. IMRT was commonly associated with errors in machine parameters (nine of 19 errors) and data entry and interpretation (six of 19 errors). IMRT was associated with a lower rate of reported errors compared with 3D/conventional RT (0.03% vs. 0.07%, p = 0.001) and specifically fewer accessory errors (odds ratio, 0.11; 95% confidence interval, 0.01-0.78) and setup errors (odds ratio, 0.24; 95% confidence interval, 0.08-0.79). Conclusions: The rate of errors in RT delivery is low. The types of errors differ significantly between IMRT and 3D/conventional RT, suggesting that QA processes must be uniquely adapted for each technique

Optimizing Timing of Immunotherapy Improves Control of Tumors by Hypofractionated Radiation Therapy

PubMed Central

Baird, Jason R.; Savage, Talicia; Cottam, Benjamin; Friedman, David; Bambina, Shelly; Messenheimer, David J.; Fox, Bernard; Newell, Pippa; Bahjat, Keith S.; Gough, Michael J.; Crittenden, Marka R.

2016-01-01

The anecdotal reports of promising results seen with immunotherapy and radiation in advanced malignancies have prompted several trials combining immunotherapy and radiation. However, the ideal timing of immunotherapy with radiation has not been clarified. Tumor bearing mice were treated with 20Gy radiation delivered only to the tumor combined with either anti-CTLA4 antibody or anti-OX40 agonist antibody. Immunotherapy was delivered at a single timepoint around radiation. Surprisingly, the optimal timing of these therapies varied. Anti-CTLA4 was most effective when given prior to radiation therapy, in part due to regulatory T cell depletion. Administration of anti-OX40 agonist antibody was optimal when delivered one day following radiation during the post-radiation window of increased antigen presentation. Combination treatment of anti-CTLA4, radiation, and anti-OX40 using the ideal timing in a transplanted spontaneous mammary tumor model demonstrated tumor cures. These data demonstrate that the combination of immunotherapy and radiation results in improved therapeutic efficacy, and that the ideal timing of administration with radiation is dependent on the mechanism of action of the immunotherapy utilized. PMID:27281029

Radiation dosimetry predicts IQ after conformal radiation therapy in pediatric patients with localized ependymoma

SciTech Connect

Merchant, Thomas E.; Kiehna, Erin N.; Li Chenghong

2005-12-01

Purpose: To assess the effects of radiation dose-volume distribution on the trajectory of IQ development after conformal radiation therapy (CRT) in pediatric patients with ependymoma. Methods and Materials: The study included 88 patients (median age, 2.8 years {+-} 4.5 years) with localized ependymoma who received CRT (54-59.4 Gy) that used a 1-cm margin on the postoperative tumor bed. Patients were evaluated with tests that included IQ measures at baseline (before CRT) and at 6, 12, 24, 36, 48, and 60 months. Differential dose-volume histograms (DVH) were derived for total-brain, supratentorial-brain, and right and left temporal-lobe volumes. The data were partitionedmore » into three dose intervals and integrated to create variables that represent the fractional volume that received dose over the specified intervals (e.g., V{sub 0-20Gy}, V{sub 20-40Gy}, V{sub 40-65Gy}) and modeled with clinical variables to develop a regression equation to estimate IQ after CRT. Results: A total of 327 IQ tests were performed in 66 patients with infratentorial tumors and 20 with supratentorial tumors. The median follow-up was 29.4 months. For all patients, IQ was best estimated by age (years) at CRT; percent volume of the supratentorial brain that received doses between 0 and 20 Gy, 20 and 40 Gy, and 40 and 65 Gy; and time (months) after CRT. Age contributed significantly to the intercept (p > 0.0001), and the dose-volume coefficients were statistically significant (V{sub 0-20Gy}, p = 0.01; V{sub 20-40Gy}, p < 0.001; V{sub 40-65Gy}, p = 0.04). A similar model was developed exclusively for patients with infratentorial tumors but not supratentorial tumors. Conclusion: Radiation dosimetry can be used to predict IQ after CRT in patients with localized ependymoma. The specificity of models may be enhanced by grouping according to tumor location.« less

Stereotactic body radiation therapy planning with duodenal sparing using volumetric-modulated arc therapy vs intensity-modulated radiation therapy in locally advanced pancreatic cancer: A dosimetric analysis

SciTech Connect

Kumar, Rachit; Wild, Aaron T.; Ziegler, Mark A.

2013-10-01

Stereotactic body radiation therapy (SBRT) achieves excellent local control for locally advanced pancreatic cancer (LAPC), but may increase late duodenal toxicity. Volumetric-modulated arc therapy (VMAT) delivers intensity-modulated radiation therapy (IMRT) with a rotating gantry rather than multiple fixed beams. This study dosimetrically evaluates the feasibility of implementing duodenal constraints for SBRT using VMAT vs IMRT. Non–duodenal sparing (NS) and duodenal-sparing (DS) VMAT and IMRT plans delivering 25 Gy in 1 fraction were generated for 15 patients with LAPC. DS plans were constrained to duodenal D{sub max} of<30 Gy at any point. VMAT used 1 360° coplanar arc with 4° spacingmore » between control points, whereas IMRT used 9 coplanar beams with fixed gantry positions at 40° angles. Dosimetric parameters for target volumes and organs at risk were compared for DS planning vs NS planning and VMAT vs IMRT using paired-sample Wilcoxon signed rank tests. Both DS VMAT and DS IMRT achieved significantly reduced duodenal D{sub mean}, D{sub max}, D{sub 1cc}, D{sub 4%}, and V{sub 20} {sub Gy} compared with NS plans (all p≤0.002). DS constraints compromised target coverage for IMRT as demonstrated by reduced V{sub 95%} (p = 0.01) and D{sub mean} (p = 0.02), but not for VMAT. DS constraints resulted in increased dose to right kidney, spinal cord, stomach, and liver for VMAT. Direct comparison of DS VMAT and DS IMRT revealed that VMAT was superior in sparing the left kidney (p<0.001) and the spinal cord (p<0.001), whereas IMRT was superior in sparing the stomach (p = 0.05) and the liver (p = 0.003). DS VMAT required 21% fewer monitor units (p<0.001) and delivered treatment 2.4 minutes faster (p<0.001) than DS IMRT. Implementing DS constraints during SBRT planning for LAPC can significantly reduce duodenal point or volumetric dose parameters for both VMAT and IMRT. The primary consequence of implementing DS constraints for VMAT is increased dose to other

Intensity-modulated radiation therapy: a review with a physics perspective.

PubMed

Cho, Byungchul

2018-03-01

Intensity-modulated radiation therapy (IMRT) has been considered the most successful development in radiation oncology since the introduction of computed tomography into treatment planning that enabled three-dimensional conformal radiotherapy in 1980s. More than three decades have passed since the concept of inverse planning was first introduced in 1982, and IMRT has become the most important and common modality in radiation therapy. This review will present developments in inverse IMRT treatment planning and IMRT delivery using multileaf collimators, along with the associated key concepts. Other relevant issues and future perspectives are also presented.

Parecoxib: an enhancer of radiation therapy for colorectal cancer.

PubMed

Xiong, Wei; Li, Wen-Hui; Jiang, Yong-Xin; Liu, Shan; Ai, Yi-Qin; Liu, Rong; Chang, Li; Zhang, Ming; Wang, Xiao-Li; Bai, Han; Wang, Hong; Zheng, Rui; Tan, Jing

2015-01-01

To study the effect of parecoxib, a novel cyclooxygenase-2 selective inhibitor, on the radiation response of colorectal cancer (CRC) cells and its underlying mechanisms. Both in vitro colony formation and apoptosis assays as well as in vivo mouse xenograft experiments were used to explore the radiosensitizing effects of parecoxib in human HCT116 and HT29 CRC cells. Parecoxib sensitized CRC cells to radiation in vitro with a sensitivity enhancement ratio of 1.32 for HCT116 cells and 1.15 for HT29 cells at a surviving fraction of 0.37. This effect was partially attributable to enhanced apoptosis induction by parecoxib combined with radiation, as illustrated using an in vitro apoptosis assays. Parecoxib augmented the tumor response of HCT116 xenografts to radiation, achieving growth delay more than 20 days and an enhancement factor of 1.53. In accordance with the in vitro results, parecoxib combined with radiation resulted in less proliferation and more apoptosis in tumors than radiation alone. Radiation monotherapy decreased microvessel density (MVD) and microvessel intensity (MVI), but increased the hypoxia level in xenografts. Parecoxib did not affect MVD, but it increased MVI and attenuated hypoxia. Parecoxib can effectively enhance radiation sensitivity in CRC cells through direct effects on tumor cells and indirect effects on tumor vasculature.

Hyperbaric oxygen therapy for the treatment of radiation-induced xerostomia: a systematic review.

PubMed

Fox, Nyssa F; Xiao, Christopher; Sood, Amit J; Lovelace, Tiffany L; Nguyen, Shaun A; Sharma, Anand; Day, Terry A

2015-07-01

Radiation-induced xerostomia is one of the most common morbidities of radiation therapy in patients with head and neck cancer. However, in spite of its high rate of occurrence, there are few effective therapies available for its management. The aim of this study was to assess the efficacy of hyperbaric oxygen on the treatment of radiation-induced xerostomia and xerostomia-related quality of life. PubMed, Google Scholar, and the Cochrane Library were searched for retrospective or prospective trials assessing subjective xerostomia, objective xerostomia, or xerostomia-related quality of life. To be included, patients had to have received radiation therapy for head and neck cancer, but not hyperbaric oxygen therapy (HBOT). The systematic review initially identified 293 potential articles. Seven studies, comprising 246 patients, qualified for inclusion. Of the included studies, 6 of 7 were prospective in nature, and 1 was a retrospective study; and 2 of the 7 were controlled studies. HBOT may have utility for treating radiation-induced xerostomia refractory to other therapies. Additionally, HBOT may induce long-term improvement in subjective assessments of xerostomia, whereas other therapies currently available only provide short-term relief. The strength of these conclusions is limited by the lack of randomized controlled clinical trials. Copyright © 2015 Elsevier Inc. All rights reserved.

Systematic review of hyperbaric oxygen therapy for the treatment of radiation-induced skin necrosis.

PubMed

Borab, Zachary; Mirmanesh, Michael D; Gantz, Madeleine; Cusano, Alessandro; Pu, Lee L Q

2017-04-01

Every year, 1.2 million cancer patients receive radiation therapy in the United States. Late radiation tissue injury occurs in an estimated 5-15% of these patients. Tissue injury can include skin necrosis, which can lead to chronic nonhealing wounds. Despite many treatments available to help heal skin necrosis such as hyperbaric oxygen therapy, no clinical guidelines exist and evidence is lacking. The purpose of this review is to identify and comprehensively summarize studies published to date to evaluate the effectiveness of hyperbaric oxygen therapy for the treatment of radiation-induced skin necrosis. Adhering to PRISMA guidelines, a systematic review of currently published articles was performed, evaluating the use of hyperbaric oxygen to treat skin necrosis. Eight articles were identified, including one observational cohort, five case series, and two case reports. The articles describe changes in symptoms and alteration in wound healing of radiation-induced skin necrosis after treatment with hyperbaric oxygen therapy. Hyperbaric oxygen therapy is a safe intervention with promising outcomes; however, additional evidence is needed to endorse its application as a relevant therapy in the treatment of radiation-induced skin necrosis. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Laser therapy by noncoherent light field of radiation.

PubMed

Djibladze, M I; Melikishvili, Z G; Uchaneishvili, S D

1997-01-01

Conducted researches on study of interaction of radiation with blood have shown, that the interaction is the most effective for light with wavelengths in the range of 600-1000 nm that corresponds to the minimum absorption factor of the whole blood. Calculations show, that at interaction of radiation with blood considerably grows effective (electronic) temperature of biological environment, that results in sharp increase of speed of biochemical reactions. The absence of necessity of application of laser radiation coherence in lasertherapy permits to create high efficient noncoherent sources of light on the basis of the GaALAs(Zn) crystals, radiating with two maxima of wavelengths 675 and 900 nm. The radiation spectrum of GaALAs(Zn) crystals falls in the most favourable area of a blood absorption spectrum.

Finger's amniotic membrane buffer technique: protecting the cornea during radiation plaque therapy.

PubMed

Finger, Paul T

2008-04-01

To use amniotic membranes as a buffer between the cornea and radioactive eye plaques. Six melanomas were treated with ophthalmic plaque radiation therapy. Plaque-tumor localization required that a portion of the gold plaque touch the cornea during treatment. To enhance patient comfort and protect the cornea, an (0.1-mm-thick) amniotic membrane was interposed between the metal plaque edge and the cornea. Minimal ocular discomfort was noted during plaque radiation therapy. On a scale of 1 (none) to 10 (severe), all 6 patients reported pain levels of 1. As a tissue equivalent and because the mean thickness was only 0.1 mm, amniotic membranes had no significant effect on radiation dose calculations. No adverse effects, infections, or abrasions were noted. The amniotic membrane buffer technique improves patient comfort and protects the cornea during ophthalmic plaque radiation therapy.

Misadministration of radiation therapy in veterinary medicine: a case report and literature review.

PubMed

Arkans, M M; Gieger, T L; Nolan, M W

2017-03-01

Recent technical advancements in radiation therapy have allowed for improved targeting of tumours and sparing nearby normal tissues, while simultaneously decreasing the risk for medical errors by incorporating additional safety checks into electronic medical record keeping systems. The benefits of these new technologies, however, depends on their proper integration and use in the oncology clinic. Despite the advancement of technology for treatment delivery and medical record keeping, misadministration errors have a significant impact on patient care in veterinary oncology. The first part of this manuscript describes a medical incident that occurred at an academic veterinary referral hospital, in a dog receiving a combination of stereotactic radiation therapy and full-course intensity-modulated, image-guided radiation therapy. The second part of the report is a literature review, which explores misadministration errors and novel challenges which arise with the implementation of advancing technologies in veterinary radiation oncology. © 2015 John Wiley & Sons Ltd.

Genital condyloma virus infection following pelvic radiation therapy: report of seven cases

SciTech Connect

Lowell, D.M.; Livolsi, V.A.; Ludwig, M.E.

1983-01-01

Six women who underwent radiation therapy for gynecologic malignancies demonstrated cytologic evidence of condyloma virus infection 2 or more years following radiation. Histologic confirmation was obtained in two of the cases. A seventh patient developed in situ and invasive squamous cell carcinoma in a vulvar condyloma acuminatum following radiation therapy for Hodgkin's disease. This venereal infection is found most frequently in sexually active younger women (average age, 27 years). It is felt that depressed cell-mediated immunity consequent to the radiation therapy allowed the development of this infection in the older patients described in this report. The evolution of invasive squamousmore » cell carcinoma in the condyloma acuminatum may indicate a possible oncogenic or cocarcinogenic effect of the virus. The immunologic responses to infection caused by the human papillomavirus group are discussed, as well as its potential for malignant transformation.« less

Assessing Adverse Events of Postprostatectomy Radiation Therapy for Prostate Cancer: Evaluation of Outcomes in the Regione Emilia-Romagna, Italy

SciTech Connect

Showalter, Timothy N., E-mail: tns3b@virginia.edu; Hegarty, Sarah E.; Division of Biostatistics, Department of Pharmacology and Experimental Therapeutics, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania

Purpose: Although the likelihood of radiation-related adverse events influences treatment decisions regarding radiation therapy after prostatectomy for eligible patients, the data available to inform decisions are limited. This study was designed to evaluate the genitourinary, gastrointestinal, and sexual adverse events associated with postprostatectomy radiation therapy and to assess the influence of radiation timing on the risk of adverse events. Methods: The Regione Emilia-Romagna Italian Longitudinal Health Care Utilization Database was queried to identify a cohort of men who received radical prostatectomy for prostate cancer during 2003 to 2009, including patients who received postprostatectomy radiation therapy. Patients with prior radiation therapymore » were excluded. Outcome measures were genitourinary, gastrointestinal, and sexual adverse events after prostatectomy. Rates of adverse events were compared between the cohorts who did and did not receive postoperative radiation therapy. Multivariable Cox proportional hazards models were developed for each class of adverse events, including models with radiation therapy as a time-varying covariate. Results: A total of 9876 men were included in the analyses: 2176 (22%) who received radiation therapy and 7700 (78%) treated with prostatectomy alone. In multivariable Cox proportional hazards models, the additional exposure to radiation therapy after prostatectomy was associated with increased rates of gastrointestinal (rate ratio [RR] 1.81; 95% confidence interval [CI] 1.44-2.27; P<.001) and urinary nonincontinence events (RR 1.83; 95% CI 1.83-2.80; P<.001) but not urinary incontinence events or erectile dysfunction. The addition of the time from prostatectomy to radiation therapy interaction term was not significant for any of the adverse event outcomes (P>.1 for all outcomes). Conclusion: Radiation therapy after prostatectomy is associated with an increase in gastrointestinal and genitourinary adverse events

Acupuncture in Treating Dry Mouth Caused By Radiation Therapy in Patients With Head and Neck Cancer | Division of Cancer Prevention

Cancer.gov

RATIONALE: Acupuncture may help relieve dry mouth caused by radiation therapy. PURPOSE: This randomized phase III trial is studying to see how well one set of acupuncture points work in comparison to a different set of acupuncture points or standard therapy in treating dry mouth caused by radiation therapy in patients with head and neck cancer. |

[Brain metastases: Focal treatment (surgery and radiation therapy) and cognitive consequences].

PubMed

Reygagne, Emmanuelle; Du Boisgueheneuc, Foucaud; Berger, Antoine

2017-04-01

Brain metastases represent the first cause of malignant brain tumor. Without radiation therapy, prognosis was poor with fast neurological deterioration, and a median overall survival of one month. Nowadays, therapeutic options depend on brain metastases presentation, extra brain disease, performance status and estimated prognostic (DS GPA). Therefore, for oligometastatic brain patients with a better prognosis, this therapeutic modality is controversial. In fact, whole-brain radiation therapy improves neurological outcomes, but it can also induce late neuro-cognitive sequelae for long-term survivors of brain metastases. Thus, in this strategy for preserving good cognitive functions, stereotactic radiation therapy is a promising treatment. Delivering precisely targeted radiation in few high-doses in one to four brain metastases, allows to reduce radiation damage to normal tissues and it should allow to decrease radiation-induced cognitive decline. In this paper, we will discuss about therapeutic strategies (radiation therapy and surgery) with their neuro-cognitive consequences for brain metastases patients and future concerning preservation of cognitive functions. Copyright © 2016 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

Refusal of curative radiation therapy and surgery among patients with cancer.

PubMed

Aizer, Ayal A; Chen, Ming-Hui; Parekh, Arti; Choueiri, Toni K; Hoffman, Karen E; Kim, Simon P; Martin, Neil E; Hu, Jim C; Trinh, Quoc-Dien; Nguyen, Paul L

2014-07-15

Surgery and radiation therapy represent the only curative options for many patients with solid malignancies. However, despite the recommendations of their physicians, some patients refuse these therapies. This study characterized factors associated with refusal of surgical or radiation therapy as well as the impact of refusal of recommended therapy on patients with localized malignancies. We used the Surveillance, Epidemiology, and End Results program to identify a population-based sample of 925,127 patients who had diagnoses of 1 of 8 common malignancies for which surgery and/or radiation are believed to confer a survival benefit between 1995 and 2008. Refusal of oncologic therapy, as documented in the SEER database, was the primary outcome measure. Multivariable logistic regression was used to investigate factors associated with refusal. The impact of refusal of therapy on cancer-specific mortality was assessed with Fine and Gray's competing risks regression. In total, 2441 of 692,938 patients (0.4%) refused surgery, and 2113 of 232,189 patients (0.9%) refused radiation, despite the recommendations of their physicians. On multivariable analysis, advancing age, decreasing annual income, nonwhite race, and unmarried status were associated with refusal of surgery, whereas advancing age, decreasing annual income, Asian American race, and unmarried status were associated with refusal of radiation (P<.001 in all cases). Refusal of surgery and radiation were associated with increased estimates of cancer-specific mortality for all malignancies evaluated (hazard ratio [HR], 2.80, 95% confidence interval [CI], 2.59-3.03; P<.001 and HR 1.97 [95% CI, 1.78-2.18]; P<.001, respectively). Nonwhite, less affluent, and unmarried patients are more likely to refuse curative surgical and/or radiation-based oncologic therapy, raising concern that socioeconomic factors may drive some patients to forego potentially life-saving care. Copyright © 2014 Elsevier Inc. All rights reserved.

Refusal of Curative Radiation Therapy and Surgery Among Patients With Cancer

SciTech Connect

Aizer, Ayal A., E-mail: aaaizer@partners.org; Chen, Ming-Hui; Parekh, Arti

Purpose: Surgery and radiation therapy represent the only curative options for many patients with solid malignancies. However, despite the recommendations of their physicians, some patients refuse these therapies. This study characterized factors associated with refusal of surgical or radiation therapy as well as the impact of refusal of recommended therapy on patients with localized malignancies. Methods and Materials: We used the Surveillance, Epidemiology, and End Results program to identify a population-based sample of 925,127 patients who had diagnoses of 1 of 8 common malignancies for which surgery and/or radiation are believed to confer a survival benefit between 1995 and 2008.more » Refusal of oncologic therapy, as documented in the SEER database, was the primary outcome measure. Multivariable logistic regression was used to investigate factors associated with refusal. The impact of refusal of therapy on cancer-specific mortality was assessed with Fine and Gray's competing risks regression. Results: In total, 2441 of 692,938 patients (0.4%) refused surgery, and 2113 of 232,189 patients (0.9%) refused radiation, despite the recommendations of their physicians. On multivariable analysis, advancing age, decreasing annual income, nonwhite race, and unmarried status were associated with refusal of surgery, whereas advancing age, decreasing annual income, Asian American race, and unmarried status were associated with refusal of radiation (P<.001 in all cases). Refusal of surgery and radiation were associated with increased estimates of cancer-specific mortality for all malignancies evaluated (hazard ratio [HR], 2.80, 95% confidence interval [CI], 2.59-3.03; P<.001 and HR 1.97 [95% CI, 1.78-2.18]; P<.001, respectively). Conclusions: Nonwhite, less affluent, and unmarried patients are more likely to refuse curative surgical and/or radiation-based oncologic therapy, raising concern that socioeconomic factors may drive some patients to forego potentially life

The Clinical Development of Molecularly Targeted Agents in Combination With Radiation Therapy: A Pharmaceutical Perspective

SciTech Connect

Ataman, Ozlem U., E-mail: ouataman@hotmail.com; Sambrook, Sally J.; Wilks, Chris

2012-11-15

Summary: This paper explores historical and current roles of pharmaceutical industry sponsorship of clinical trials testing radiation therapy combinations with molecularly targeted agents and attempts to identify potential solutions to expediting further combination studies. An analysis of clinical trials involving a combination of radiation therapy and novel cancer therapies was performed. Ongoing and completed trials were identified by searching the (clinicaltrials.gov) Web site, in the first instance, with published trials of drugs of interest identified through American Society of Clinical Oncology, European CanCer Organisation/European Society for Medical Oncology, American Society for Radiation Oncology/European Society for Therapeutic Radiology and Oncology, andmore » PubMed databases and then cross-correlated with (clinicaltrials.gov) protocols. We examined combination trials involving radiation therapy with novel agents and determined their distribution by tumor type, predominant molecular mechanisms examined in combination to date, timing of initiation of trials relative to a novel agent's primary development, and source of sponsorship of such trials. A total of 564 studies of targeted agents in combination with radiation therapy were identified with or without concomitant chemotherapy. Most studies were in phase I/II development, with only 36 trials in phase III. The tumor site most frequently studied was head and neck (26%), followed by non-small cell lung cancer. Pharmaceutical companies were the sponsors of 33% of studies overall and provided support for only 16% of phase III studies. In terms of pharmaceutical sponsorship, Genentech was the most active sponsor of radiation therapy combinations (22%), followed by AstraZeneca (14%). Most radiation therapy combination trials do not appear to be initiated until after drug approval. In phase III studies, the most common (58%) primary endpoint was overall survival. Collectively, this analysis suggests

[A case of lung metastasis from esophageal cancer resistant to fluorouracil and cisplatin combination therapy but responsive to radiation therapy].

PubMed

Ami, Katsunori; Seki, Ryouta; Takasaki, Jun; Amagasa, Hidetoshi; Kamikozuru, Hirotaka; Ganno, Hideaki; Kurokawa, Toshiaki; Fukuda, Akira; Nagahama, Takeshi; Ando, Masayuki; Yamada, Yosuke; Kodaka, Fumi; Arai, Kuniyoshi

2012-11-01

At present, fluorouracil and cisplatin combination therapy is the standard chemotherapy against esophageal cancer, but the choice of second-line chemotherapy is controversial. Furthermore, the effect of radiation therapy against lung metastasis from esophageal cancer is unclear. We report a case of lung metastasis from esophageal cancer resistant to fluorouracil and cisplatin combination therapy but responsive to radiation therapy. The patient was a 55-year-old woman who had undergone an operation for esophageal cancer at another hospital. A single right lung metastasis appeared 1 year after the operation. Combined fluorouracil and cisplatin therapy was administrated for 5 courses, but the lung metastasis increased in size. Afterwards, she was admitted to our hospital. We treated her with 14 courses of S-1 and docetaxel combination therapy administered over 13 months. The lung metastasis was decreased for a period. Furthermore, radiofrequency ablation under computed tomography was performed against the lung metastasis re-growth at another hospital. Although the lung metastasis increased in size, no further metastases were detected during the clinical course. The patient was treated with radiotherapy for the lung metastasis re-growth. The tumor had almost disappeared by 10 months after the completion of radiotherapy. Currently, she is receiving palliative care as an outpatient and the lung metastasis has not been evident for 2 years since the completion of radiotherapy.

Initial clinical outcomes of audiovisual-assisted therapeutic ambience in radiation therapy (AVATAR).