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1

Risk Factors for Cataract After Palladium103 Ophthalmic Plaque Radiation Therapy  

Microsoft Academic Search

Purpose: To examine how tumor characteristics and dose affect cataract development after plaque radiation therapy. Methods and Materials: Three hundred and eighty-four patients were diagnosed with uveal melanoma and treated with palladium-103 (¹°³Pd) plaque radiation therapy. Of these, 282 (74%) inclusion met exclusion criteria for follow-up time, tumor location, and phakic status. Then patient-, ophthalmic-, and radiation-specific factors (patient age,

Paul T. Finger; Kimberly J. Chin; Guo-Pei Yu; Neil S. Patel

2011-01-01

2

Risk Factors for Cataract After Palladium-103 Ophthalmic Plaque Radiation Therapy  

SciTech Connect

Purpose: To examine how tumor characteristics and dose affect cataract development after plaque radiation therapy. Methods and Materials: Three hundred and eighty-four patients were diagnosed with uveal melanoma and treated with palladium-103 ({sup 103}Pd) plaque radiation therapy. Of these, 282 (74%) inclusion met exclusion criteria for follow-up time, tumor location, and phakic status. Then patient-, ophthalmic-, and radiation-specific factors (patient age, diabetes, hypertension, tumor location, tumor dimensions, and lens dose) were examined (by a Cox proportional regression model) as predictors for the development of radiation-related cataract. Results: Radiation cataract developed in 76 (24%) of patients at a mean follow-up of 39.8 months (range, 1-192). Patients with anteriorly located tumors were noted to have a higher incidence of cataract at 43.0% (43 of 100 patients) vs. 18.1% (33 cataracts per 182 patients) for posteriorly located tumors (p <0.0001). However, multivariate Cox proportional modeling showed that increasing patient age at time of treatment (p for trend = 0.0003) and higher lens dose (p for trend = 0.001) were the best predictors (biomarkers) for radiation cataract. Conclusions: Although anterior tumor location, greater tumor height, and increased patient age (at treatment) were associated with significantly greater risk for radiation cataract, dose to lens was the most significant factor.

Finger, Paul T., E-mail: pfinger@eyecancer.com [New York Eye Cancer Center, New York, NY (United States); New York Eye and Ear Infirmary, New York, NY (United States); Chin, Kimberly J. [New York Eye Cancer Center, New York, NY (United States); Yu Guopei [New York Eye and Ear Infirmary, New York, NY (United States); Patel, Neil S. [New York Eye Cancer Center, New York, NY (United States); New York Eye and Ear Infirmary, New York, NY (United States)

2011-07-01

3

[{sup 18}F]Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (PET/CT) Physiologic Imaging of Choroidal Melanoma: Before and After Ophthalmic Plaque Radiation Therapy  

SciTech Connect

Purpose: To evaluate changes in [{sup 18}F]fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) standardized uptake values (SUV) in uveal melanoma before and after plaque brachytherapy. Methods and Materials: A cohort of 217 patients diagnosed with uveal melanoma and eligible for ophthalmic plaque brachytherapy underwent preoperative PET/CT to evaluate their intraocular tumor and screen for metastasis. Subsequent to undergoing plaque brachytherapy, patients' PET/CT SUV were periodically reevaluated over 42 months. Results: In this series, 37 (17%) choroidal melanoma patients were found to have an SUV of >2.0. Of these, 18 patients were able to undergo interval follow-up PET/CT scanning. There were 3 patients with T2, 11 patients with T3, and 4 patients with T4 melanomas according to 7th edition AJCC-UICC criteria. Mean apical thickness was 8.8 mm (range, 3-12.3 mm), and the largest mean tumor diameter was 15.1 mm (range, 12-19.9 mm). The mean initial SUV was 3.7 (range, 2.1-7.3). Patients were followed for a median 16 months (range, 6-42 months). The median time to a tumor SUV of 0 was 8.0 months (range, 6-18 months). There was one case of one interval increase in SUV that diminished after circumferential laser treatment. Conclusions: Intraocular PET/CT imaging provides a physiological assessment of tumor metabolism that can be used to evaluate changes after treatment. In this study, ophthalmic plaque radiation therapy was associated with extinguished tumor PET/CT SUV over time. PET/CT imaging can be used to assess choroidal melanomas for their response to treatment.

Finger, Paul T., E-mail: pfinger@eyecancer.co [New York Eye Cancer Center, New York City, New York (United States); Chin, Kimberly J. [New York Eye Cancer Center, New York City, New York (United States)

2011-01-01

4

Radiation Therapy  

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... person can start feeling well again. How Is Radiation Given? Cancer can be treated with radiation therapy ... of cancer kids get. Continue What Happens During Radiation Therapy? Because the radiation treatment needs to be ...

5

Radiation Therapy  

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... weeks. New Techniques Newer radiation techniques such as proton beam radiotherapy, which uses a different form of ... requiring many more beams than conventional radiation therapy. Proton Beam Therapy compared to traditional photon beam radiation, ...

6

Radiation regression patterns after cobalt plaque insertion for retinoblastoma  

SciTech Connect

An analysis of 31 eyes of 30 patients who had been treated with cobalt plaques for retinoblastoma disclosed that a type I radiation regression pattern developed in 15 patients; type II, in one patient, and type III, in five patients. Nine patients had a regression pattern characterized by complete destruction of the tumor, the surrounding choroid, and all of the vessels in the area into which the plaque was inserted. This resulting white scar, corresponding to the sclerae only, was classified as a type IV radiation regression pattern. There was no evidence of tumor recurrence in patients with type IV regression patterns, with an average follow-up of 6.5 years, after receiving cobalt plaque therapy. Twenty-nine of these 30 patients had been unsuccessfully treated with at least one other modality (ie, light coagulation, cryotherapy, external beam radiation, or chemotherapy).

Buys, R.J.; Abramson, D.H.; Ellsworth, R.M.; Haik, B.

1983-08-01

7

Radiation Therapy  

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... how to cope with side effects. What Is Radiation Therapy? Cancer is a disease that causes cells ... when they're giving radiation treatments. How Is Radiation Given? Doctors can give people with cancer radiation ...

8

Radiation Therapy  

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... rays, but the power can also come from protons or other types of energy. The term "radiation ... Why it's done Mayo Clinic products and services Proton beam therapy at Mayo Clinic Radiation therapy at ...

9

Radiation Therapy  

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Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

10

Radiation therapy  

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... can also damage or kill healthy cells. The death of healthy cells can lead to side effects. These side effects depend on the dose of radiation, and how often you have the therapy. External beam radiation may cause skin changes, such as hair loss, red or ...

11

Professions in Radiation Therapy  

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Professions in: Radiation Therapy Radiation Oncologist Medical Radiation Physicist Radiation Therapist Dosimetrist Radiation Oncology Nurse Social Worker Dietitian Radiation Oncologist Radiation oncologists ...

12

Gene therapy for the vulnerable plaque  

Microsoft Academic Search

Rupture of coronary atherosclerotic plaque and subsequent formation of an occlusive intracoronary thrombus (Figure 410-1)\\u000a are the major events precipitating acute coronary syndromes [16]. The vulnerable plaque is smaller in size [7], richer in lipids [1],[2], and more infiltrated with macrophages [2,3,810] than the stable, fibromuscular lesion. Therefore, lowering the lipid and\\/or macrophage pools stored in the plaque may stabilize

Douglas W. Losordo; Jeffrey M. Isner

13

Plaque Therapy and Scatter Dose Using {sup 252}Cf Sources  

SciTech Connect

As melanomas are radioresistant to conventional low-linear energy transfer (LET) radiations such as photons and electrons, {sup 252}Cf (high-LET due to neutrons) may offer more promising clinical results. Although {sup 252}Cf also emits photons and electrons, the majority of absorbed dose is imparted by the high-LET radiation. This study examines the impact of scattering material on the neutron dose distributions for {sup 252}Cf plaque therapy (used to treat surface lesions like melanoma). Neutrons were transported through a 10-cm-diam water phantom with a thickness of either 5 or 10 cm using the MCNP radiation transport code. The phantom was surrounded by vacuum; the {sup 252}Cf neutron energy spectrum was modeled as a Maxwellian distribution; and the source was a bare point positioned at 1.0, 0.5, or {epsilon} above or below the water/vacuum interface. These source positions were chosen to mimic the case where a plaque locates the source either above the skin's surface, e.g., 2{pi} scattering geometry, or if layers of tissue-equivalent bolus materials were placed atop the implant to provide radiation backscatter, 4{pi} geometry. Differences between the 2{pi} and 4{pi} geometries were maximized closest to the source and for source positions farthest from the water/vacuum interface. Therefore, the maximum radiation dose (closest to the {sup 252}Cf source) may be minimized by not including scattering material for plaque therapy. However, for nonrelativistic, elastic scattering for protons by neutrons, the proton range increases with neutron energy. This result was expected since the neutron energy spectrum degrades at increasing depth and the proportion of fast neutron dose to total dose is maximized closest to the source in the 2{pi} geometry. Future studies will examine this effect as a function of neutron energy, will consider synergy with the low-LET {sup 252}Cf dose component and include experimental measurements, and will assess this technique to possibly improve in vivo dose distributions.

Mark J. Rivard; Anita Mahajan

2000-11-12

14

Radiation Therapy for Osteosarcoma  

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... for osteosarcoma Next Topic Clinical trials for osteosarcoma Radiation therapy for osteosarcoma Radiation therapy uses high-energy rays ... major role in treating this disease. External beam radiation therapy This is the type of radiation therapy most ...

15

Gallbladder Cancer: Radiation Therapy  

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... gallbladder cancer Next Topic Chemotherapy for gallbladder cancer Radiation therapy for gallbladder cancer Radiation therapy uses high- ... higher dose to the cancer areas. Uses of radiation therapy Radiation therapy may be used in several ...

16

Radiation Therapy (For Parents)  

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... have many questions and concerns about it. About Radiation Therapy In radiation therapy, high-energy radiation from ... to remove tumors or cancerous areas. Continue How Radiation Is Given Radiation therapy is administered two ways: ...

17

Antiangiogenic therapy for normalization of atherosclerotic plaque vasculature: a potential strategy for plaque stabilization.  

PubMed

Angiogenesis within human atherosclerotic plaques has an important role in plaque progression as immature blood vessels leak red blood cells and inflammatory mediators into the plaque center. Accumulation of free cholesterol from red blood cell membranes potentially increases the size of the necrotic core and triggers a chain of events that promote plaque destabilization. Antiangiogenic agents have been shown to prune some tumor vessels and 'normalize' the structure and function of the remaining vasculature, thereby improving the access of chemotherapeutic agents to tumors. We propose that antiangiogenic therapy can similarly stabilize vulnerable 'rupture-prone' plaques by pruning and normalizing immature intraplaque vessels, preventing further intraplaque hemorrhage. This normalization would limit necrotic core enlargement, further luminal narrowing and the degree of inflammation. Such normalization has been realized using vascular endothelial growth factor antagonists for the treatment of cancer and age-related macular degeneration. The development of this novel approach to prevent plaque progression might add to the armamentarium of preventive measures for acute myocardial infarction, stroke and sudden cardiac death. PMID:17712362

Jain, Rakesh K; Finn, Aloke V; Kolodgie, Frank D; Gold, Herman K; Virmani, Renu

2007-09-01

18

Detection and Therapy of Vulnerable Plaque with Fluorescent and/or Radiolabeled Compositions.  

National Technical Information Service (NTIS)

The present invention relates to methods for selectively targeting Photodynamic Therapy ('PDT') to inflammatory components of vulnerable plaques. As such, the present invention provides methods for the identification of vulnerable plaques, using fluoresce...

A. Fischman A. Tawakol J. Muller M. R. Hamblin T. Hasan

2002-01-01

19

Antiangiogenic therapy for normalization of atherosclerotic plaque vasculature: a potential strategy for plaque stabilization  

Microsoft Academic Search

Angiogenesis within human atherosclerotic plaques has an important role in plaque progression as immature blood vessels leak red blood cells and inflammatory mediators into the plaque center. Accumulation of free cholesterol from red blood cell membranes potentially increases the size of the necrotic core and triggers a chain of events that promote plaque destabilization. Antiangiogenic agents have been shown to

Aloke V Finn; Frank D Kolodgie; Renu Virmani; Rakesh K Jain; Herman K Gold

2007-01-01

20

Radiation Therapy for Bone Cancer  

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... bone cancer Next Topic Chemotherapy for bone cancer Radiation therapy for bone cancer Radiation therapy uses high- ... control symptoms like pain and swelling. Intensity-modulated radiation therapy Intensity-modulated radiation therapy (IMRT) is an ...

21

Radiation Therapy for Malignant Mesothelioma  

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... malignant mesothelioma Next Topic Chemotherapy for malignant mesothelioma Radiation therapy for malignant mesothelioma Radiation therapy uses high- ... this form of treatment more useful. Uses of radiation therapy Radiation therapy may be used in different ...

22

Prostate Cancer (Radiation Therapy)  

MedlinePLUS

... control the cancer. If I choose surgery, will radiation treatment still be required? If your surgery is ... option with your physician team. If I choose radiation therapy, will surgical treatment still be an option? ...

23

Gene Therapy and Radiation  

Microsoft Academic Search

\\u000a Owing to a low efficiency of gene transfer when delivered systemically, gene therapy may find its greatest utility in the\\u000a clinic when combined with loco-regional cancer treatment such as radiation therapy. Although a variety of gene therapy strategies\\u000a have been combined with radiation in preclinical models, only a handful have been translated into the clinic. Overall, combining\\u000a gene therapy with

Svend O. Freytag; Kenneth N. Barton; Farzan Siddiqui; Mohamed Elshaikh; Hans Stricker; Benjamin Movsas

24

Association of statin therapy with reduced coronary plaque rupture: an optical coherence tomography study  

PubMed Central

Objective Statin therapy induces plaque regression and may stabilize atheromatous plaques. Optical coherence tomography (OCT) is a high-resolution in-vivo imaging modality that allows characterization of atherosclerotic plaques. We aimed to demonstrate the potential utility of OCT in evaluating coronary plaques in patients with or without statin therapy. Methods Patients undergoing cardiac catheterization were enrolled. We identified culprit lesions and performed intracoronary OCT imaging. Plaque lipid pool, fibrous cap thickness, and frequency of thin-cap fibroatheroma were evaluated using previously validated criteria. Macrophage density was determined from optical signals within fibrous caps. Presence of calcification, thrombosis, and rupture was assessed. Results Forty-eight patients were included (26 on statins, 22 without statins). Baseline characteristics were similar apart from lipid profile. Patients on statin therapy had lower total and low-density lipoprotein cholesterol concentrations (4.45 1.35 vs. 5.26 0.83 mmol/l, P = 0.02; 2.23 0.78 vs. 3.26 0.62 mmol/l, P < 0.001, respectively). Frequencies of lipid-rich plaque (69 vs. 82%), thin-cap fibroatheroma (31 vs. 50%), plaque calcification (15 vs. 5%) and thrombosis (15 vs. 32%), and fibrous cap macrophage density were comparable between statin and nonstatin groups (5.9 vs. 6.3%; all P =NS). Ruptured plaques were, however, significantly less frequent in patients on established statin therapy (8 vs. 36%; P = 0.03) with a trend toward increased minimum fibrous cap thickness (78 vs. 49 ?m; P = 0.07). Conclusion We demonstrated the use of OCT in plaque characterization and found that patients on prior statin therapy have reduced incidence of ruptured plaques and a trend toward thicker fibrous caps. This suggests that statins may stabilize coronary plaques.

Chia, Stanley; Raffel, Owen Christopher; Takano, Masamichi; Tearney, Guillermo J.; Bouma, Brett E.; Jang, Ik-Kyung

2009-01-01

25

Radiation complications and tumor control after {sup 125}I plaque brachytherapy for ocular melanoma  

SciTech Connect

Purpose: To determine the outcome of {sup 125}I plaque brachytherapy at our institution and identify the risk factors associated with the development of radiation complications, tumor recurrence, and metastasis. Patients and Methods: From 1986 to 2000, 156 patients underwent {sup 125}I episcleral plaque (COMS design) application for the treatment of ocular melanoma. Chart analysis of follow-up ophthalmologic appointments assessed the incidence of ocular side effects after therapy. Statistical analysis assessed outcomes and significant influencing factors. Results: With a median follow-up of 6.2 years, the 5-year overall survival was 83%. The 5-year disease-specific survival was 91%. Initial local control at 5 years was 92%, with 100% ultimate local control after secondary therapy that included 9 enucleations. The risk of metastasis was 10% at 5 years and 27% at 10 years. Vision stayed the same or improved in 25% of patients, and 44% of patients maintained visual acuity better than 20/200. Thirteen percent of patients experienced chronic pain or discomfort in the treated eye. Dose rates to the tumor apex greater than 90 to 100 cGy/h were associated with increased systemic control but worse radiation toxicity. Conclusion: Patients in our series experienced excellent local tumor control. Higher dose rates to the tumor apex were associated with reduced rates of distant metastases but worse ocular function.

Jensen, Ashley W. [Department of Radiation Oncology, Mayo Medical School, Mayo Clinic College of Medicine, Rochester, MN (United States); Petersen, Ivy A. [Division of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)]. E-mail: petersen.ivy@mayo.edu; Kline, Robert W. [Division of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Stafford, Scott L. [Division of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Schomberg, Paula J. [Division of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Robertson, Dennis M. [Department of Ophthalmology, Mayo Clinic, Rochester, MN (United States)

2005-09-01

26

Microenvironment and Radiation Therapy  

PubMed Central

Dependency on tumor oxygenation is one of the major features of radiation therapy and this has led many radiation biologists and oncologists to focus on tumor hypoxia. The first approach to overcome tumor hypoxia was to improve tumor oxygenation by increasing oxygen delivery and a subsequent approach was the use of radiosensitizers in combination with radiation therapy. Clinical use of some of these approaches was promising, but they are not widely used due to several limitations. Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that is activated by hypoxia and induces the expression of various genes related to the adaptation of cellular metabolism to hypoxia, invasion and metastasis of cancer cells and angiogenesis, and so forth. HIF-1 is a potent target to enhance the therapeutic effects of radiation therapy. Another approach is antiangiogenic therapy. The combination with radiation therapy is promising, but several factors including surrogate markers, timing and duration, and so forth have to be optimized before introducing it into clinics. In this review, we examined how the tumor microenvironment influences the effects of radiation and how we can enhance the antitumor effects of radiation therapy by modifying the tumor microenvironment.

Yoshimura, Michio; Itasaka, Satoshi; Harada, Hiroshi; Hiraoka, Masahiro

2013-01-01

27

External Radiation Therapy  

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... mark where the differences between success rates with radical prostatectomy and radiation therapy become evident,and if you' ... to put you through a major operation like radical prostatectomy, and in those situations, I do refer patients ...

28

Stereotactic Body Radiation Therapy  

Microsoft Academic Search

\\u000a Technological advancements in imaging and radiation planning and delivery have made it possible for cranial stereotactic radiosurgery\\u000a techniques to be applied to tumors outside of the brain. Although high-dose radiation therapy may be delivered in a single\\u000a fraction, referred to as extracranial stereotactic radiosurgery (SRS), more often, high-precision radiation is delivered in\\u000a more than one fraction, leading to the field

Laura A. Dawson

29

Bile Duct (Cholangiocarcinoma) Cancer: Radiation Therapy  

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... cancer Next Topic Chemotherapy for bile duct cancer Radiation therapy for bile duct cancer Radiation therapy is ... are different kinds of radiation therapy. External beam radiation therapy (EBRT) This type of radiation therapy uses ...

30

Radiation Therapy for Lung Cancer  

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... visit: National Cancer Institute www.cancer.gov/clinicaltrials Radiation Therapy Answers www.rtanswers.org STRO AMERICAN SOCIETY FOR ... of the lung cancer and your overall health. Radiation Therapy Radiation is a high-energy X-ray that ...

31

Radiation Therapy: Additional Treatment Options  

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... Prostate Skin Upper GI Latest Research Find a Radiation Oncologist Last Name: Facility: City: State: Zip Code: ... infections. This is refered to as immunotherapy . Intraoperative Radiation Therapy Radiation therapy given during surgery is called ...

32

Effects of carbon dioxide, Nd-YAG, and argon laser radiation on coronary atheromatous plaques.  

PubMed

Laser radiation has been successfully applied in several areas of medical practice. However, its use in cardiology and specifically its effects on obstructive atherosclerosis have largely been unexplored. To evaluate effects of laser radiation on atherosclerotic plaques 25 fresh necropsy atherosclerotic coronary artery segments were exposed to laser radiation with either a carbon dioxide, Nd-YAG, or argon laser. Split or intact segments were prepared under dry conditions or while immersed in saline solution or blood and exposed to laser radiation as power and duration of exposure varied. All 3 lasers were capable of creating controlled injury to atherosclerotic plaques. In general, the magnitude of injury varied according to the total energy delivered (that is, power times duration of exposure. Calcified and noncalcified plaques were penetrated with similar levels of injury. Histologic examination demonstrated that laser radiation produced a wedge incision in the atherosclerotic plaque which was surrounded by zones of thermal and acoustic injury. PMID:6816057

Abela, G S; Normann, S; Cohen, D; Feldman, R L; Geiser, E A; Conti, C R

1982-12-01

33

Monte Carlo dosimetry for 125I and 60Co in eye plaque therapy.  

PubMed

Monte Carlo calculations of radiation dosimetry using MORSE code are performed for 125I and 60Co point sources in a cylindrical head phantom that simulates the geometry of eye plaque therapy for choroidal melanoma. We obtain the dose variation in the eye at submillimeter intervals over distances as close as 1 mm and up to 2.5 cm from the source. The calculations for 125I are performed for the phantom media of water, protein, and a homogenized protein-water mixture simulating the composition of the eye. Relative dose functions for 125I for these phantom media are fitted to second-degree polynomials. Agreement is found with published results. The relative dose function for 60Co at eye position in the water head phantom is fitted to a third-degree polynomial and compared with that for 60Co at the center of a large water sphere. A boundary effect due to the head phantom-air interface on the dose distribution for 60Co is demonstrated. The dose falloff with distance is faster for the eye geometry compared with the bulk geometry. We also show that the relative dose distributions within the tumor are comparable for 125I and 60Co by comparing their relative dose functions. This result is consistent with the success of clinical trials of large melanoma treatments with 125I plaques. PMID:3784996

Chiu-Tsao, S T; O'Brien, K; Sanna, R; Tsao, H S; Vialotti, C; Chang, Y S; Rotman, M; Packer, S

34

Radiation Therapy for Skin Cancer  

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... melanoma.org Skin Cancer Foundation www.skincancer.org Radiation Therapy Answers www.rtanswers.org AMERICAN SOCIETY FOR RADIATION ... visit: National Cancer Institute www.cancer.gov/clinicaltrials Radiation Therapy Answers www.rtanswers.org Radiation Therapy Oncology Group ...

35

Complications of radiation therapy  

SciTech Connect

The skeletal effects of radiation are dependent upon many variables, but the pathologic features are consistent. Radiation may cause immediate or delayed cell death, cellular injury with recovery, arrest of cellular division, or abnormal repair with neoplasia. Radiation necrosis and radiation-induced neoplasm still occur despite the use of supervoltage therapy. Complications of radiotherapy are well known and have led to more judicious use of this therapeutic modality. With few exceptions, benign bone tumors are no longer treated with irradiation. Radiation necrosis may be difficult to differentiate from sarcoma arising in irradiated bone. They both occur within the field of irradiation. Radiation necrosis often has a long latent period which is, of course, the rule in radiation-induced neoplasia. A soft tissue mass favors the diagnosis of neoplasia, while its absence suggests radiation necrosis. Lack of pain favors necrosis. Calcification may occur in radiation necrosis and does not indicate neoplasia. A lack of progression on serial roentgenograms also favors radiation necrosis. 76 references.

Dalinka, M.K.; Mazzeo, V.P. Jr.

1985-01-01

36

Stereotactic body radiation therapy.  

PubMed

Stereotactic body radiation therapy constitutes an emerging therapeutic paradigm. These treatments are unique relative to the large body of experience with conventional fractionated radiotherapy. On the basis of the treatment principles of intracranial stereotactic radiation combined with enhancements associated with immobilization and imaging, the role of extracranial treatment continues to evolve. However, most clinical reports on extracranial treatments suffer from short or incomplete follow-up, making final assessments of benefit and toxicity, particularly late toxicity, problematic. These techniques are centered on a very basic understanding of the use of ionizing radiation for the treatment of cancer. Nonetheless, they do require a unique and special understanding of radiobiologic and physics principles. It is hoped that using high-dose, single-fraction treatment or a few fractions of treatment, the therapeutic ratio is improved, thus potentially changing the way some cancers are treated. Ideally, all patients receiving such treatments would be enrolled in formal protocols. As data accrue and understanding of these techniques improve, it will be possible to better define the indications for stereotactic body radiation therapy. At that time, appropriate applications can be submitted for permanent billing codes that will describe a process of care that embraces this technology without vendor favoritism. This review summarizes the state of stereotactic body radiation in 2005. PMID:17411904

Potters, Louis; Timmerman, Robert; Larson, David

2005-08-01

37

Palladium-103 Radiation Therapy for Small Choroidal Melanoma.  

PubMed

PURPOSE: To evaluate outcomes after ophthalmic plaque radiation therapy for small choroidal melanomas. DESIGN: Retrospective study, case series. PARTICIPANTS: Seventy-two patients with choroidal melanomas ?1.5 and ?2.4 mm apical height and ?10 mm width treated between 2002 and 2012, with a minimum follow-up of 8 months. METHODS: All patients were treated with palladium-103 plaque brachytherapy. Mean radiation dose to the tumor apex was 82.4 Gy (range, 70.0-102 Gy). MAIN OUTCOME MEASURES: Local control, radiation complications, visual acuity, and metastatic rate. RESULTS: Plaque radiotherapy provided 100% local tumor control and eye retention at a mean 54 months of observation (95% confidence interval, 46-63 months). The most common long-term brachytherapy-related complications were radiation maculopathy (43.1%) and radiation optic neuropathy (20.8%) developing at a mean of 27 months (range, 9-72 months) after irradiation. In this series, 94.4% of patients maintained 20/200 or better vision. There has been no small choroidal melanoma-related metastasis. CONCLUSIONS: Palladium-103 plaque radiation therapy offered excellent local control and visual acuity outcomes for patients with small choroidal melanoma. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article. PMID:23774104

Semenova, Ekaterina; Finger, Paul T

2013-06-14

38

Sarcoma - Adult Soft Tissue Cancer: Radiation Therapy  

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... sarcomas Next Topic Chemotherapy for soft tissue sarcomas Radiation therapy for soft tissue sarcomas Radiation therapy uses ... spread. This is called palliative treatment. Types of radiation therapy External beam radiation therapy: For this treatment, ...

39

Measurement of intima-media thickness vs. carotid plaque: uses in patient care, genetic research and evaluation of new therapies.  

PubMed

Intima-media thickness (IMT) has been measured for over 20 years, and is widely regarded as a surrogate for atherosclerosis. However, in the carotid arteries atherosclerosis is focal, manifesting as plaques. IMT is often measured deliberately where no plaque exists, or multiple measurements may be averaged, including only one or two that intersect plaque. IMT and plaque are biologically and genetically distinct, so they can be expected to respond differentially to therapies for atherosclerosis. Furthermore, because plaques grow along the carotid arteries 2.4 times faster than they thicken, progression or regression of total plaque area is more sensitive to effects of therapy than IMT. Because plaques also grow and regress circumferentially, three-dimensional (3-D) plaque volume is two orders of magnitude more sensitive to effects of therapy than is IMT. While 3-D ultrasound requires special equipment, total plaque area can be measured using the same equipment as IMT. Because plaque and IMT are biologically and genetically distinct entities, representing different phenotypes of atherosclerosis, both should be measured in any situation where IMT is measured, with the exception of studies in children too young for the occurrence of plaque. IMT should not be called 'atherosclerosis': the phenotype being assessed should be specified. PMID:18706019

Spence, J David

2006-11-01

40

Radiation Therapy for Vaginal Cancer  

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... internal radiation with or without low doses of chemotherapy. Side effects of radiation therapy Radiation can destroy nearby healthy ... occur, but can be treated with medicines. These side effects tend to be worse when chemotherapy is given with radiation. Pelvic radiation can lead ...

41

Radiation Therapy for Testicular Cancer  

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... therapy for testicular cancer Radiation therapy uses a beam of high-energy rays (such as gamma rays or x-rays) or particles (such as electrons, protons, or neutrons) to destroy cancer cells or ...

42

[Radiation therapy in thyroid cancer].  

PubMed

Anaplastic thyroid cancers represent 1-2% of all thyroid tumours and are of very poor prognosis even with multimodality treatment including external beam radiation therapy. Conversely, differentiated thyroid carcinomas (at least 80% of thyroid cancers) hamper good prognosis with surgery with or without radioiodine and there is hardly any room for external beam radiation therapy. Insular and medullar carcinomas have intermediary prognosis and are rarely irradiated. We aimed to update recommendations for external beam irradiation in these different clinical situations and put in light the benefits of new irradiations techniques. A search of the French and English literature was performed using the following keywords: thyroid carcinoma, anaplastic, chemoradiation, radiation therapy, surgery, histology and prognostic. Non-mutilating surgery (often limited to debulking) followed by systematic external beam radiation therapy is the standard of care in anaplastic thyroid cancers (hyperfractionated-accelerated radiation therapy with low-dose weekly doxorubicin with or without cisplatin if possible). Given anaplastic thyroid cancers' median survival of 10 months or less, neoadjuvant and adjuvant chemotherapy may also be discussed. Ten-year survival rates for patients with papillary, follicular and Hrthle-cell carcinomas are 93%, 85%, and 76%, respectively. Massive primary incompletely resected iodine-negative disease indicates external beam radiation therapy. Older age (45 or 60-year-old), poor-prognosis histological variants (including tall cell cancers) and insular cancers are increasingly reported as criteria for external beam radiation therapy. Massive extracapsular incompletely resected nodal medullary disease suggests external beam radiation therapy. Radiation therapy morbidity has been an important limitation. However, intensity modulated radiation therapy (IMRT) offers clear dosimetric advantages on tumour coverage and organ sparing, reducing late toxicities to less than 5%. The role of radiation therapy is evolving for anaplastic thyroid cancers using multimodal strategies and new chemotherapy molecules, and for differentiated cancers using minor criteria, such as histological variants, with IMRT becoming a standard of care. PMID:23763764

Sun, X S; Guevara, N; Fakhry, N; Sun, S-R; Marcy, P-Y; Santini, J; Bosset, J-F; Thariat, J

2013-02-08

43

Solitary plaque mycosis fungoides on the penis responding to topical imiquimod therapy.  

PubMed

Mycosis fungoides (MF) presenting in the genitalia is rare. We report a case of long-standing penile MF in a young man. Commonly used treatments for limited plaque MF include topical corticosteroids and ultraviolet light therapy. There are a few anecdotal reports on the use of topical imiquimod in MF. Our patient responded well and remained in complete remission after treatment with topical imiquimod. PMID:17300249

Chiam, L Y T; Chan, Y C

2007-03-01

44

Elimination of neoangiogenesis for plaque stabilization: is there a role for local drug therapy?  

PubMed

Emerging data suggest that intraplaque hemorrhage is critical in promoting atherosclerotic lesion instability. Because red blood cell membranes are a rich source of free cholesterol and accumulated red blood cells within plaques promote inflammation, intraplaque hemorrhage is associated with expansion of the necrotic core. Plaque hemorrhage results from the development of immature neointimal vasa vasorum. Therefore, it is proposed that molecular therapies designed to eliminate pathologic neovascularization within developing lesions will interrupt the process of hemorrhage and decrease the rate of necrotic core expansion. The elimination of intraplaque neovascularization would involve targeting of pre-existing and new vessel development. The concept of vascular regression has met some success in other neovascular-dependent diseases, including macular degeneration and malignancies. The efficacy of this novel approach is dependent on gaining critical knowledge of the environment required to support development and maturation of the vasa vasorum within varying plaque types. A multitargeted approach involving selective local antiangiogenic agents should contribute to prevention of plaque progression and its clinical consequences. PMID:17531658

Kolodgie, Frank D; Narula, Jagat; Yuan, Chun; Burke, Allen P; Finn, Aloke V; Virmani, Renu

2007-05-17

45

Radiation Therapy for Kidney Cancer  

MedlinePLUS

... special type of radiation therapy known as stereotactic radiosurgery can sometimes be used for single tumors that ... surgery. There are 2 main techniques for stereotactic radiosurgery, but they all use the same principle of ...

46

Manifestation of palmoplantar pustulosis during or after infliximab therapy for plaque-type psoriasis: report on five cases  

PubMed Central

Infliximab is a monoclonal antibody directed against TNF-?. It has been approved for use in rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease, psoriatic arthritis and plaque-type psoriasis. In case reports, positive effects on pustular variants of psoriasis have also been reported. However, paradoxically, manifestation of pustular psoriasis and plaque-type psoriasis has been reported in patients treated with TNF antagonists including infliximab for other indications. Here, we report on 5 patients with chronic plaque-type psoriasis who developed palmoplantar pustulosis during or after discontinuation of infliximab therapy. In two of the five cases, manifestation of palmoplantar pustulosis was not accompanied by worsening of plaque-type psoriasis. Possibly, site-specific factors or a differential contribution of immunological processes modulated by TNF inhibitors to palmoplantar pustulosis and plaque-type psoriasis may have played a role.

Thaci, Diamant; Mohr, Johannes; Patzold, Sylvie; Bertsch, Hans Peter; Kruger, Ullrich; Reich, Kristian

2008-01-01

47

Radiation Therapy for Ewing Tumors  

MedlinePLUS

... as the spine or pelvis (hip bones). Conformal proton beam radiation therapy: Proton beam therapy is related to 3D-CRT and uses ... x-rays like most other techniques, it focuses proton beams on the tumor. Protons are positive parts of ...

48

Method for microbeam radiation therapy  

DOEpatents

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.

Slatkin, Daniel N. (Sound Beach, NY); Dilmanian, F. Avraham (Yaphank, NY); Spanne, Per O. (Shoreham, NY)

1994-01-01

49

Stereotactic Body Radiation Therapy: Fractionated Radiation Therapy Perspective  

Microsoft Academic Search

\\u000a The introduction of intracranial stereotactic radiosurgery in 1951 is widely attributed to Lars Leksell [1]. As initially developed, the method delivered a single dose of radiation to a target lesion, which was localized using the\\u000a principles of stereotaxy. Current treatment strategies in stereotactic body radiation therapy (SBRT) are an extension of these\\u000a principles applied to extracranial sites. Techniques that allow

Gordon W. Wong; Rafael R. Maon; Wolfgang Tom; Minesh Mehta

50

Radiation Therapy Oncology Group  

MedlinePLUS

... to be Showcased at ASTRO 2013 RTOG Investigator William Small, Jr, MD, Named Gynecologic Cancer Intergroup Chair-Elect and Radiation Oncology Dept. Chair at Loyola University Remembrances of RTOG Investigator Kian Ang, MD, PhD Copyright (c) 2013 RTOG | Privacy Statement | Login RTOG is funded ...

51

Radiation therapy for gliomas  

Microsoft Academic Search

Radiotherapy remains one of the cornerstones of treatment of patients with gliomas. Radiation- induced damage to DNA can result in the loss of proliferative capacity of neoplastic cells. In addition to mitotic cell death, it has recently been found that other cellular events can lead to reproductive failure. Apoptosis, or programmed cell death, has been described as a response to

Edward G. Soltesz; Abel Jaramillo; Frederick A. Tibayan; Peter M. Black

1999-01-01

52

Radiation therapy in proliferative vitreoretinopathy  

Microsoft Academic Search

In a prospective study of the effect of postoperative radiation therapy for the prevention of reproliferation of membranes and recurrent proliferative vitreoretinopathy (PVR) two similar groups of patients with retinal detachment and PVR grade D1 to D3 in one eye were compared. Half the eyes (30) received a total dose of 3000 cGy after surgery; the other half remained untreated.

Susanne Binder; Mireille Bonnet; Michaela Velikay; Jean-Pierre Gerard; Ulrike Stolba; Andreas Wedrich; Hannelore Hohenberg

1994-01-01

53

Lack of Radiation Maculopathy After Palladium-103 Plaque Radiotherapy for Iris Melanoma  

SciTech Connect

Purpose: To report on the risk of radiation maculopathy for iris and iridociliary melanomas treated by {sup 103}Pd plaque radiotherapy. Methods and Materials: This is a retrospective clinical case series of 30 eyes in 30 patients with melanomas limited to the iris or invading the ciliary body. The main outcome measures included demographic information, laterality, tumor size, location, visual acuity, radiation dose, local control, retinal evaluation, and duration of follow-up. Results: Thirty patients were followed for a median 36 months (range, 12-90 months). Sixteen of 30 tumors (53%) were pure iris melanomas, and 14 (47%) were primary iris melanomas extending into the ciliary body. Radiation dosimetry showed that the median tumor apex dose was 85 Gy (range, 75-100 Gy), lens dose 43.5 Gy (range, 17.8-60 Gy), fovea dose 1.8 Gy (range, 1.3-5 Gy), and central optic disc dose 1.7 Gy (range, 1.3-4.7 Gy). Cataracts developed in 20 of the 28 phakic eyes (71.4%). No patient in this series developed radiation maculopathy or radiation optic neuropathy. Last best-corrected visual acuity was {>=}20/25 in 28 patients (93%) at a median 36 months' follow-up. Conclusion: Though visual acuities were transiently affected by radiation cataract, no radiation maculopathy or optic neuropathy has been noted after {sup 103}Pd treatment of iris and iridociliary melanomas.

Yousef, Yacoub A. [New York Eye Cancer Center, New York Eye and Ear Infirmary, and New York University School of Medicine, New York, NY (United States); Finger, Paul T., E-mail: pfinger@eyecancer.com [New York Eye Cancer Center, New York Eye and Ear Infirmary, and New York University School of Medicine, New York, NY (United States)

2012-07-15

54

Radiation therapy of esophageal cancer  

SciTech Connect

Radiation therapy has been used extensively in the management of patients with cancer of the esophagus. It has demonstrated an ability to cure a small minority of patients. Cure is likely to be limited to patients who have lesions less than 5 cm in length and have minimal, if any, involvement of lymph nodes. Esophagectomy is likely to cure a similar, small percentage of patients with the same presentation of minimal disease but has a substantial acute postoperative mortality rate and greater morbidity than irradiation. Combining surgery and either preoperative or postoperative irradiation may cure a small percentage of patients beyond the number cured with either modality alone. Radiation has demonstrated benefit as an adjuvant to surgery following the resection of minimal disease. However, radiation alone has never been compared directly with surgery for the highly select, minimal lesions managed by surgery. Radiation provides good palliation of dysphagia in the majority of patients, and roughly one third may have adequate swallowing for the duration of their illness when ''radical'' doses have been employed. Surgical bypass procedures have greater acute morbidity but appear to provide more reliable, prolonged palliation of dysphagia. Several approaches to improving the efficacy of irradiation are currently under investigation. These approahces include fractionation schedules, radiosensitizers, neutron-beam therapy, and helium-ion therapy.

Hancock, S.L.; Glatstein, E.

1984-06-01

55

Rapid changes in plaque composition and morphology after intensive lipid lowering therapy: study with serial coronary CT angiography  

PubMed Central

Although intensive lipid lowering by statins can enhance plaque stability, few data exist regarding how early statins change plaque composition and morphology in clinical setting. Therefore, to examine early changes in plaque composition and morphology by intensive lipid lowering with statins, we evaluate coronary plaques from acute coronary syndrome (ACS) before and 3 weeks after lipid lowering by coronary CT angiography. We enrolled 110 patients with suspected ACS and underwent coronary CT. We defined plaque as unstable when CT number of plaque< 50HU and remodeling index (lesion diameter/reference diameter) >1.10. Rosuvastatin (5 mg/day) or atorvastatin (20 mg/day) were introduced to reduce low density lipoprotein cholesterol (LDL-C). Then, CT was again performed by the same condition 3 weeks after lipid lowering therapy. Total 10 patients (8 men, mean age 72.0 years), in whom informed consent regarding serial CT examination was obtained, were analyzed. Among them, 4 patients who denied to have intensive lipid lowering were served as controls. In remaining 6 patients, LDL-C reduced from 129.526.9 mg/dl to 68.511.1 mg/dl after statin treatment. Under these conditions, CT number of the targeted plaque significantly increased from 16.015.9 to 50.835.0 HU (p<0.05) and remodeling index decreased from 1.220.11 to 1.110.06 (p<0.05), although these values substantially unchanged in controls. These results demonstrate that MDCT-determined plaque composition as well as volume could be changed within 3 weeks after intensive lipid lowering. This may explain acute effects of statins in treatment of acute coronary syndrome.

Shimojima, Masaya; Kawashiri, Masa-aki; Nitta, Yutaka; Yoshida, Taiji; Katsuda, Shouji; Kaku, Bunji; Taguchi, Tomio; Hasegawa, Akira; Konno, Tetsuo; Hayashi, Kenshi; Yamagishi, Masakazu

2012-01-01

56

Radiation Therapy and Hearing Loss  

SciTech Connect

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-associated ototoxicity as well as a detailed approach for scoring toxicity is presented.

Bhandare, Niranjan [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida (United States); Jackson, Andrew [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Eisbruch, Avraham; Pan, Charlie C. [Department of Radiation Oncology, University of Michigan (United States); Flickinger, John C. [Department of Radiation Oncology, University of Pittsburgh Medical Center (United States); Antonelli, Patrick [Department of Otolaryngology, University of Florida College of Medicine, Gainesville, Florida (United States); Mendenhall, William M., E-mail: mendwm@shands.ufl.ed [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida (United States)

2010-03-01

57

Radiation Therapy in Geriatric Oncology  

Microsoft Academic Search

Personalizing a patients course of cancer therapy is of utmost relevance to the geriatric population. Advances in diagnostic\\u000a radiology and radiation technology have improved tolerability for this group and expanded treatment options. Better images\\u000a to visualize the tumor with PET\\/CT or MRI can be registered to the CT data acquired with the patient in the treatment position\\u000a so that a

Sarah E. Hoffe; Mark S. Russell

58

Direct photodynamic therapy for vulnerable plaque: investigation of light dosimetry for depth control  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) mechanism with high-intensity pulsed laser excitation has not been well understood. We think complete understanding of this unknown effect in PDT leads perfect treated depth control at various lesions. To realize the depth controlled PDT for atheromatous plaque therapy with a fibrous cap intact and surrounding damage free, we studied PDT against murine macrophage-like cells in vitro with the second-generation chlorin photosensitizer manufactured by Photochemical Co. Ltd. (Okayama Japan). The relation between the excitation conditions (pulse energy density and repetition rate) and PDT photocytotoxicity was examined in vitro. The XeCl excimer laser pumped dye laser (wavelength: 669+/-3 nm, pulse duration: 7ns in FWHM) was used with the pulse energy density from 1.2 to 9.5 mJ/cm2, and the pulse repetition rate from 5 to 80 Hz. Under higher pulse energy density condition, no significant PDT photocytotoxicity was obtained. We examined the photobleaching of the protein containing photosensitizer medium solution, which is considered to correlates with the generation of singlet oxygen. Under higher pulse energy condition, the photobleaching efficiency decrease was observed and the measured PDT effect decrease in terms of laser pulse energy density could be explained by the photobleaching. We measured the oxygen partial pressure in photosensitizer medium solution immediately after the laser exposure. The decrease of oxygen partial pressure, i.e., the amount of the oxygen consumption during the laser exposure was observed 46 mmHg under the excitation condition of the pulse energy density of 9.5 mJ/cm2, the total fluence of 5 J/cm2, the repetition rate of 80Hz, and correlated with the bleaching efficiency 87% under the same condition. We calculated cell death distribution in depth direction based on measured photocytotoxicity under various pulse energy densities. The possibility of depth controlled PDT for safety atheromatous plaque therapy was suggested by the PDT effect alteration depending on pulse energy density.

Ohmori, Sayaka; Yanagihara, Takeshi; Arai, Tsunenori

2004-07-01

59

Adjuvant radiation therapy for stage II thymoma  

Microsoft Academic Search

Background. Thymoma is difficult to study because of its indolent natural history. The criteria for administration of adjuvant radiation therapy remain controversial, and it is unclear whether patients with Masaoka stage II thymoma benefit from adjuvant radiation. The goal of this report was to determine whether or not this group benefits from radiation therapy in terms of disease-specific survival and

Abeel A Mangi; Cameron D Wright; James S Allan; John C Wain; Dean M Donahue; Hermes C Grillo; Douglas J Mathisen

2002-01-01

60

Overview of image-guided radiation therapy  

Microsoft Academic Search

Radiation therapy has gone through a series of revolutions in the last few decades and it is now possible to produce highly conformal radiation dose distribution by using techniques such as intensity-modulated radiation therapy (IMRT). The improved dose conformity and steep dose gradients have necessitated enhanced patient localization and beam targeting techniques for radiotherapy treatments. Components affecting the reproducibility of

Lei Xing; Brian Thorndyke; Eduard Schreibmann; Yong Yang; Tian-Fang Li; Gwe-Ya Kim; Gary Luxton; Albert Koong

2006-01-01

61

Radiation therapy and breast reconstruction.  

PubMed

Mastectomy will continue to play a substantial role in the treatment of breast cancer, because many women either are not candidates for or do not desire to have breast conservation. Many patients treated with mastectomy will desire reconstruction, and many of these will be advised to receive adjuvant radiotherapy, which has been shown to increase overall survival in certain high risk patients. There continues to be considerable controversy regarding the compatibility of radiation therapy and breast reconstruction due to increased complications and decreased cosmetic outcome. These can be minimized by careful modern surgical and radiation techniques, and in most cases the result is acceptable, including for reconstructions with prosthetic implants as well as autogenous myocutaneous flaps. PMID:9572684

Moulds, J E; Berg, C D

1998-01-01

62

Targeted Radiation Therapy for Cancer Initiative.  

National Technical Information Service (NTIS)

This program is intended to establish the infrastructure to provide state-of-the art targeted radiation therapy to military personnel and veterans with cancer. The research aspect of this project is intended to demonstrate whether: (1) targeted radiation ...

D. MacDonald

2011-01-01

63

Clinical and microbiological benefits of strict supragingival plaque control as part of the active phase of periodontal therapy  

PubMed Central

Aim To compare the clinical and microbiological effects of scaling and root planing (SRP) alone or combined with mechanical (professional plaque control - PPC) or chemical (chlorhexidine rinsing - CHX) control of supragingival plaque in the treatment of chronic periodontitis. Methods Sixty subjects were randomly assigned to receive SRP alone or combined with PPC (twice a week) or with CHX rinsing (twice a day). The adjunctive treatments began with SRP and continued for 42 days. Clinical and microbiological examinations were performed at baseline, 2 and 6 months post-therapy. Subgingival plaque samples were analyzed for 38 bacterial species by checkerboard DNA-DNA hybridization. Results The two test treatments were more effective in improving probing depth and clinical attachment level (CAL) than SRP alone, even in intermediate and deep sites. CAL gain was better maintained in the CHX group. The most beneficial microbiological changes were observed in CHX-treated subjects, who showed a significant reduction in the proportions of red and orange complexes, as well as an increase in the proportions of the host-compatible bacterial species. Conclusion Strict plaque control performed during and after SRP improves periodontal treatment outcomes. The greatest microbiological and clinical benefits were observed with the use of CHX rinsing.

FERES, Magda; GURSKY, Lauren Christine; FAVERI, Marcelo; TSUZUKI, Claudia Ota; FIGUEIREDO, Luciene Cristina

2009-01-01

64

Radiation therapy for Graves' disease  

SciTech Connect

We used radiation therapy (a total of 2,000 rads) to treat 14 patients (three men and 11 women, ranging in age from 27 to 72 years) with Graves' disease. Three of these patients had refused to take corticosteroids and the other 11 had failed to respond to them, had experienced side effects, or had other contraindications to their use. After follow-up periods ranging from six months to three years, soft-tissue inflammation was reduced in 13 of the 14 patients. All but two patients showed a decrease in proptosis of 1 to 3 mm. Myopathy showed the least improvement. Although we noted transient eyelid erythema, there were no permanent sequelae and none of the patients has had a recurrence of the inflammation.

Brennan, M.W.; Leone, C.R. Jr.; Janaki, L.

1983-08-01

65

Melioidosis: reactivation during radiation therapy  

SciTech Connect

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 bronchogenic 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.

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

1980-05-01

66

Advanced Semiconductor Dosimetry in Radiation Therapy  

SciTech Connect

Modern radiation therapy is very conformal, resulting in a complexity of delivery that leads to many small radiation fields with steep dose gradients, increasing error probability. Quality assurance in delivery of such radiation fields is paramount and requires real time and high spatial resolution dosimetry. Semiconductor radiation detectors due to their small size, ability to operate in passive and active modes and easy real time multichannel readout satisfy many aspects of in vivo and in a phantom quality assurance in modern radiation therapy. Update on the recent developments and improvements in semiconductor radiation detectors and their application for quality assurance in radiation therapy, based mostly on the developments at the Centre for Medical Radiation Physics (CMRP), University of Wollongong, is presented.

Rosenfeld, Anatoly B. [Centre for Medical Radiation Physics, University of Wollongong, Wollongong NSW 2522 (Australia)

2011-05-05

67

Carotid plaque regression following 6-month statin therapy assessed by 3T cardiovascular magnetic resonance: comparison with ultrasound intima media thickness  

PubMed Central

Background Cardiovascular magnetic resonance (CMR) allows volumetric carotid plaque measurement that has advantage over 2-dimensional ultrasound (US) intima-media thickness (IMT) in evaluating treatment response. We tested the hypothesis that 6-month statin treatment in patients with carotid plaque will lead to plaque regression when measured by 3 Tesla CMR but not by IMT. Methods Twenty-six subjects (67 2 years, 7 females) with known carotid plaque (> 1.1 mm) and coronary or cerebrovascular atherosclerotic disease underwent 3T CMR (T1, T2, proton density and time of flight sequences) and US at baseline and following 6 months of statin therapy (6 had initiation, 7 had increase and 13 had maintenance of statin dosing). CMR plaque volume (PV) was measured in the region 12 mm below and up to 12 mm above carotid flow divider using software. Mean posterior IMT in the same region was measured. Baseline and 6-month CMR PV and US IMT were compared. Change in lipid rich/necrotic core (LR/NC) and calcification plaque components from CMR were related to change in PV. Results Low-density lipoprotein cholesterol decreased (86 6 to 74 4 mg/dL, p = 0.046). CMR PV decreased 5.8 2% (1036 59 to 976 65 mm3, p = 0.018). Mean IMT was unchanged (1.12 0.06 vs. 1.14 0.06 mm, p = NS). Patients with initiation or increase of statins had -8.8 2.8% PV change (p = 0.001) while patients with maintenance of statin dosing had -2.7 3% change in PV (p = NS). There was circumferential heterogeneity in CMR plaque thickness with greatest thickness in the posterior carotid artery, in the region opposite the flow divider. Similarly there was circumferential regional difference in change of plaque thickness with significant plaque regression in the anterior carotid region in region of the flow divider. Change in LR/NC (R = 0.62, p = 0.006) and calcification (R = 0.45, p = 0.03) correlated with PV change. Conclusions Six month statin therapy in patients with carotid plaque led to reduced plaque volume by 3T CMR, but ultrasound posterior IMT did not show any change. The heterogeneous spatial distribution of plaque and regional differences in magnitude of plaque regression may explain the difference in findings and support volumetric measurement of plaque. 3T CMR has potential advantage over ultrasound IMT to assess treatment response in individuals and may allow reduced sample size, duration and cost of clinical trials of plaque regression.

2011-01-01

68

21 CFR 892.5300 - Medical neutron radiation therapy system.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Medical neutron radiation therapy system. 892.5300 Section...Devices § 892.5300 Medical neutron radiation therapy system. (a) Identification. A medical neutron radiation therapy system is a device...

2013-04-01

69

21 CFR 892.5840 - Radiation therapy simulation system.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Radiation therapy simulation system. 892...Therapeutic Devices § 892.5840 Radiation therapy simulation system. (a) Identification. A radiation therapy simulation system is a...

2013-04-01

70

21 CFR 892.5750 - Radionuclide radiation therapy system.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Radionuclide radiation therapy system. 892.5750 Section...Devices § 892.5750 Radionuclide radiation therapy system. (a) Identification. A radionuclide radiation therapy system is a device...

2013-04-01

71

Radiation therapy for choroidal melanoma  

Microsoft Academic Search

Radiotherapy offers patients with malignant melanoma of the choroid an eye and a vision-sparing alternative to enucleation. The most commonly used forms of radiotherapy are ophthalmic plaque brachytherapy and charged-particle (external beam) radiotherapy. Unfortunately, after all forms of radiotherapy for choroidal melanoma many patients experience sight-limiting side effects, and an average of 16.3% of patients treated with radiotherapy subsequently require

Paul T. Finger

1997-01-01

72

Galactic cosmic radiation leads to cognitive impairment and increased a? plaque accumulation in a mouse model of Alzheimer's disease.  

PubMed

Galactic Cosmic Radiation consisting of high-energy, high-charged (HZE) particles poses a significant threat to future astronauts in deep space. Aside from cancer, concerns have been raised about late degenerative risks, including effects on the brain. In this study we examined the effects of (56)Fe particle irradiation in an APP/PS1 mouse model of Alzheimer's disease (AD). We demonstrated 6 months after exposure to 10 and 100 cGy (56)Fe radiation at 1 GeV/, that APP/PS1 mice show decreased cognitive abilities measured by contextual fear conditioning and novel object recognition tests. Furthermore, in male mice we saw acceleration of A? plaque pathology using Congo red and 6E10 staining, which was further confirmed by ELISA measures of A? isoforms. Increases were not due to higher levels of amyloid precursor protein (APP) or increased cleavage as measured by levels of the ? C-terminal fragment of APP. Additionally, we saw no change in microglial activation levels judging by CD68 and Iba-1 immunoreactivities in and around A? plaques or insulin degrading enzyme, which has been shown to degrade A?. However, immunohistochemical analysis of ICAM-1 showed evidence of endothelial activation after 100 cGy irradiation in male mice, suggesting possible alterations in A? trafficking through the blood brain barrier as a possible cause of plaque increase. Overall, our results show for the first time that HZE particle radiation can increase A? plaque pathology in an APP/PS1 mouse model of AD. PMID:23300905

Cherry, Jonathan D; Liu, Bin; Frost, Jeffrey L; Lemere, Cynthia A; Williams, Jacqueline P; Olschowka, John A; O'Banion, M Kerry

2012-12-31

73

Galactic Cosmic Radiation Leads to Cognitive Impairment and Increased A? Plaque Accumulation in a Mouse Model of Alzheimer's Disease  

PubMed Central

Galactic Cosmic Radiation consisting of high-energy, high-charged (HZE) particles poses a significant threat to future astronauts in deep space. Aside from cancer, concerns have been raised about late degenerative risks, including effects on the brain. In this study we examined the effects of 56Fe particle irradiation in an APP/PS1 mouse model of Alzheimers disease (AD). We demonstrated 6 months after exposure to 10 and 100 cGy 56Fe radiation at 1 GeV/, that APP/PS1 mice show decreased cognitive abilities measured by contextual fear conditioning and novel object recognition tests. Furthermore, in male mice we saw acceleration of A? plaque pathology using Congo red and 6E10 staining, which was further confirmed by ELISA measures of A? isoforms. Increases were not due to higher levels of amyloid precursor protein (APP) or increased cleavage as measured by levels of the ? C-terminal fragment of APP. Additionally, we saw no change in microglial activation levels judging by CD68 and Iba-1 immunoreactivities in and around A? plaques or insulin degrading enzyme, which has been shown to degrade A?. However, immunohistochemical analysis of ICAM-1 showed evidence of endothelial activation after 100 cGy irradiation in male mice, suggesting possible alterations in A? trafficking through the blood brain barrier as a possible cause of plaque increase. Overall, our results show for the first time that HZE particle radiation can increase A? plaque pathology in an APP/PS1 mouse model of AD.

Cherry, Jonathan D.; Liu, Bin; Frost, Jeffrey L.; Lemere, Cynthia A.; Williams, Jacqueline P.; Olschowka, John A.; O'Banion, M. Kerry

2012-01-01

74

Radiation Sensitization in Cancer Therapy.  

ERIC Educational Resources Information Center

|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,

Greenstock, Clive L.

1981-01-01

75

Managing the adverse effects of radiation therapy.  

PubMed

Nearly two thirds of patients with cancer will undergo radiation therapy as part of their treatment plan. Given the increased use of radiation therapy and the growing number of cancer survivors, family physicians will increasingly care for patients experiencing adverse effects of radiation. Selective serotonin reuptake inhibitors have been shown to significantly improve symptoms of depression in patients undergoing chemotherapy, although they have little effect on cancer-related fatigue. Radiation dermatitis is treated with topical steroids and emollient creams. Skin washing with a mild, unscented soap is acceptable. Cardiovascular disease is a well-established adverse effect in patients receiving radiation therapy, although there are no consensus recommendations for cardiovascular screening in this population. Radiation pneumonitis is treated with oral prednisone and pentoxifylline. Radiation esophagitis is treated with dietary modification, proton pump inhibitors, promotility agents, and viscous lidocaine. Radiation-induced emesis is ameliorated with 5-hydroxytryptamine3 receptor antagonists and steroids. Symptomatic treatments for chronic radiation cystitis include anticholinergic agents and phenazopyridine. Sexual dysfunction from radiation therapy includes erectile dysfunction and vaginal stenosis, which are treated with phosphodiesterase type 5 inhibitors and vaginal dilators, respectively. PMID:20704169

Berkey, Franklin J

2010-08-15

76

Hyperbaric oxygen therapy for radiation myelitis  

SciTech Connect

Radiation therapy may damage healthy tissues adjacent to tumor. Hyperbaric oxygen therapy (HBO) is useful in treating soft tissue and osteoradionecrosis. In addition, HBO has been recommended to treat radiation-induced myelitis. We used radiation to induce a predictable myelitis in the spinal cords of rats who were randomized into treatment (HBO) and control groups 8 wk after irradiation. Serial neurologic examination showed no benefit or harm as a result of HBO. This small pilot study did not demonstrate any clinically significant benefit of HBO for radiation myelitis in rats.

Poulton, T.J.; Witcofski, R.L.

1985-12-01

77

Antivascular Endothelial Growth Factor Bevacizumab for Radiation Optic Neuropathy: Secondary to Plaque Radiotherapy  

SciTech Connect

Purpose: To evaluate the intravitreal antivascular endothelial growth factor, bevacizumab, for treatment of radiation optic neuropathy (RON). Methods and Materials: A prospective interventional clinical case series was performed of 14 patients with RON related to plaque radiotherapy for choroidal melanoma. The RON was characterized by optic disc edema, hemorrhages, microangiopathy, and neovascularization. The entry criteria included a subjective or objective loss of vision, coupled with findings of RON. The study subjects received a minimum of two initial injections of intravitreal bevacizumab (1.25 mg in 0.05 mL) every 6-8 weeks. The primary objectives included safety and tolerability. The secondary objectives included the efficacy as measured using the Early Treatment Diabetic Retinopathy Study chart for visual acuity, fundus photography, angiography, and optical coherence tomography/scanning laser ophthalmoscopy. Results: Reductions in optic disc hemorrhage and edema were noted in all patients. The visual acuity was stable or improved in 9 (64%) of the 14 patients. Of the 5 patients who had lost vision, 2 had relatively large posterior tumors, 1 had had the vision decrease because of intraocular hemorrhage, and 1 had developed optic atrophy. The fifth patient who lost vision was noncompliant. No treatment-related ocular or systemic side effects were observed. Conclusions: Intravitreal antivascular endothelial growth factor bevacizumab was tolerated and generally associated with improved vision, reduced papillary hemorrhage, and resolution of optic disc edema. Persistent optic disc neovascularization and fluorescein angiographic leakage were invariably noted. The results of the present study support additional evaluation of antivascular endothelial growth factor medications as treatment of RON.

Finger, Paul T., E-mail: pfinger@eyecancer.com [New York Eye Cancer Center, New York, NY (United States); Chin, Kimberly J. [New York Eye Cancer Center, New York, NY (United States)

2012-02-01

78

Clinical and Capillaroscopic Modifications of the Psoriatic Plaque during Therapy: Observations with Oral Acitretin  

PubMed Central

Psoriasis is considered to be an inflammatory autoimmune disease, where angiogenesis plays an undefined pathogenetic role. The well-known changes of the superficial microvasculature in the psoriatic plaque can be easily assessed in vivo by videocapillaroscopy. In the last years, several studies reported the clinical and capillaroscopic response of the psoriatic plaque during different topical and systemic treatments. In the present work we evaluated the effects of acitretin (0.8?mg/kg/day) on videocapillaroscopic alterations and the clinical response in 11 patients affected by plaque psoriasis at the baseline (T0) and after 4 (T1), 8 (T2), and 12 (T3) weeks. A clinical improvement during the treatment with a complete clinical healing of the plaque in 7 of the 11 patients was observed. The typical basket-weave capillaries of the psoriatic lesions showed a reduction of 65.4% in diameter at the end of the study; only 3 patients returned to a normal capillaroscopic pattern. As observed during previous our studies, we found a discrepancy between clinical and capillaroscopic results, with a far greater improvement in the first than in the second. This finding could be in agreement with a secondary role of blood vessels in the pathogenesis and persistence of psoriatic lesions.

Buligan, Cinzia; Errichetti, Enzo; Valent, Francesca

2013-01-01

79

Optimization of Tumour Therapy with Ionizing Radiations.  

National Technical Information Service (NTIS)

The results of tumour therapy with ionizing radiation seem not to be optimal since the tumour cells are less damaged than the normal tissue due to the lack of oxygen and the tumour cells also are able to repair much of the radiation damage. From this reas...

W. Pohlit

1980-01-01

80

Clinicopathologic report of successful cobalt 60 plaque therapy for choroidal melanoma  

SciTech Connect

A 66-year-old man had malignant melanoma of the choroid that enlarged during a two-year period while a retinal detachment developed. Treatment consisted of a cobalt 60 plaque placed to deliver a dose of 35,000 rads to the base and 9,000 rads to the apex of the tumor. Clinical response was excellent and complete regression occurred. The patient later died of an unrelated disease. Histopathologic study verified complete regression of the tumor.

Cleasby, G.W.; Kutzscher, B.M.

1985-12-15

81

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 false X-ray therapy and other radiation therapy services: Scope. 410.35...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...

2012-10-01

82

New therapeutic strategies in radiation therapy  

SciTech Connect

Radiation therapy has been an integral part of curative cancer therapy for many decades. The tolerance of normal tissues traversed by radiation and resistant tumor cell populations traditionally have limited the radiocurability of certain tumors, especially with higher clinical stages. However, research in radiobiology and radiation physics is providing ways to increase cure while limiting morbidity. Computer-controlled dynamic treatment, radioprotector drugs, hyperbaric oxygen, carbogen breathing during irradiation, particle irradiation, and hypoxic cell sensitizing drugs are presently undergoing clinical evaluation with some encouraging preliminary results. We review the fundamental concepts underlying these clinical trials and analyze the results.

Kinsella, T.J. (National Cancer Inst., Bethesda, MD); Bloomer, W.D.

1981-04-24

83

Protective prostheses during radiation therapy  

SciTech Connect

Current applications and complications in the use of radiotherapy for the treatment of oral malignancy are reviewed. Prostheses are used for decreasing radiation to vital structures not involved with the lesion but located in the field of radiation. With a program of oral hygiene and proper dental care, protective prostheses can help decrease greatly the morbidity seen with existing radiotherapy regimens.

Poole, T.S.; Flaxman, N.A.

1986-04-01

84

Radiation therapy alone versus radiation therapy and chemotherapy in the management of Hodgkin's disease.  

PubMed Central

Forty-four patients with histologically proven Hodgkin's disease underwent initial treatment with extended-field radiation therapy. Nineteen of these patients also received combination chemotherapy. For analysis, patients were assigned to three treatment groups: group 1 received radiation therapy only (25 patients); group 2 received combination chemotherapy followed by consolidative (low-dose extended-field) radiation therapy; and group 3 was treated with alternate chemotherapy and radiation therapy using the sandwich technique. The actuarial 5-year disease-free survival rates were 83% (group 1), 83% (group 2), and 100% (group 3). The overall actuarial survival rates were 96% (group 1), 92% (group 2), and 100% (group 3). No factor was identified as being of prognostic value in predicting relapse. We conclude that extended-field radiation therapy delivered in this manner is a safe and effective approach to the initial management of Hodgkin's disease.

Glenn, L. D.; Kumar, P. P.

1990-01-01

85

Radiation Therapy for Gynecologic Cancers  

MedlinePLUS

... tiny marks on your skin, like a permanent tattoo, to help the radiation therapist precisely position you ... interest in or pleasure with sexual activity, most women are able to resume sexual relations. Ask your ...

86

Radiation Therapy for Breast Cancer  

MedlinePLUS

... tiny marks on your skin, like a permanent tattoo, to help the radiation therapist precisely position you ... the most common type of cancer in American women, according to the American Cancer Society. This year, ...

87

Radiation therapy of benign diseases  

SciTech Connect

This book reports on the evaluation and treatment of benign disease. The text begins with a chapter concerning standards of practice by an eminent malpractice lawyer, thereby clarifying the medical-legal implications of the radiation treatment of benign disease. The text then lists, in alphabetic order, those benign diseases which have been or are currently treated with radiotherapy for each disease entity. A feature is the survey of current radiation practice in the United States.

Order, S.E. (Johns Hopkins Univ., Baltimore, MD (US)); Donaldson, S. (Stanford Univ., Stanford, CA (US))

1990-01-01

88

Ocular melanoma: Total dose and dose rate effects with Co-60 plaque therapy  

SciTech Connect

From 1968 to 1987, 123 consecutive patients with nonmetastatic choroidal melanoma were treated with cobalt-60 plaques. One hundred sixteen patients were followed up for a mean of 3.8 years. Twenty patients had local failure, and 14 patients had distant failure. Complications included 32 cataracts, and seven enucleations were required. Local recurrence did not correlate with tumor height, tumor volume, dose, or dose rate. Increased volume (P = .004) and height (P = .01) correlated with increased rates of distant metastases. Dose adjusted for volume did not correlate with the rate of metastases.

Beitler, J.J.; McCormick, B.; Ellsworth, R.M.; Abramson, D.H.; Anderson, L.L.; Loffredo, C. (Memorial Sloan-Kettering Cancer Center, New York, NY (USA))

1990-07-01

89

Stereotactic radiation therapy and selective internal radiation therapy for hepatocellular carcinoma  

Microsoft Academic Search

Recent technological advances allow precise and safe radiation delivery in hepatocellular carcinoma. Stereotactic body radiotherapy is a conformal external beam radiation technique that uses a small number of relatively large fractions to deliver potent doses of radiation therapy to extracranial sites. It requires stringent breathing motion control and image guidance. Selective internal radiotherapy or radioembolization refers to the injection of

A. Bujold; L. A. Dawson

2011-01-01

90

When the Synchrotron radiations highlight the Randall's plaques and kidney concretions  

NASA Astrophysics Data System (ADS)

In western countries, a dramatic increase in papilla calcifications (Randall's Plaque or RP) is observed as a major cause of calcium oxalate kidney stones. Through ex vivo X-ray absorption spectroscopy, we give for the first time direct structural evidence of the presence of amorphous carbonated calcium phosphate in these Randall's plaques (RP). Such chemical composition of RP present in increasingly young subjects raises a major question regarding alimentation: does nutrient-enriched food especially aimed at young children affect the physiology of the kidney? Moreover, lithogenic diseases may induce intratubular crystallization and end-stage renal failure. We show that Fourier transform infrared microspectroscopy is able to characterize such pathological microcalcifications giving their chemical composition and their spatial distribution, thus providing invaluable information for the diagnosis of the disease and the treatment of the patients.

Daudon, M.; Bazin, D.

2013-03-01

91

Respiratory Motion Prediction in Radiation Therapy  

NASA Astrophysics Data System (ADS)

Active respiratory motion management has received increasing attention in the past decade as a means to reduce the internal margin (IM) component of the clinical target volume (CTV)planning target volume (PTV) margin typically added around the gross tumor volume (GTV) during radiation therapy of thoracic and abdominal tumors. Engineering and technical developments in linear accelerator design and respiratory motion monitoring respectively have made the delivery of motion adaptive radiation therapy possible through real-time control of either dynamic multileaf collimator (MLC) motion (gantry based linear accelerator design) or robotic arm motion (robotic arm mounted linear accelerator design).

Vedam, Sastry

92

Radiation Therapy for Pilocytic Astrocytomas of Childhood  

SciTech Connect

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 initial 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.

Mansur, David B., E-mail: mansur@radonc.wustl.ed [Department of Radiation Oncology, Washington University School of Medicine and Saint Louis Children's Hospital, Saint Louis, MO (United States); Rubin, Joshua B. [Division of Pediatric Hematology and Oncology, Washington University School of Medicine and Saint Louis Children's Hospital, Saint Louis, MO (United States); Kidd, Elizabeth A. [Department of Radiation Oncology, Washington University School of Medicine and Saint Louis Children's Hospital, Saint Louis, MO (United States); King, Allison A. [Division of Pediatric Hematology and Oncology, Washington University School of Medicine and Saint Louis Children's Hospital, Saint Louis, MO (United States); Hollander, Abby S. [Endocrinology, Washington University School of Medicine and Saint Louis Children's Hospital, Saint Louis, MO (United States); Smyth, Matthew D.; Limbrick, David D.; Park, T.S.; Leonard, Jeffrey R. [Department of Neurological Surgery, Washington University School of Medicine and Saint Louis Children's Hospital, Saint Louis, MO (United States)

2011-03-01

93

Anesthesia for intraoperative radiation therapy in children  

SciTech Connect

Intraoperative radiation therapy (IORT) is a relatively new mode of cancer treatment which is being used with increasing frequency. IORT presents several challenges to the anesthesiologist, including patients who are debilitated from their disease or chemotherapy, operations involving major tumor resections, intraoperative interdepartmental transport of patients, and remote monitoring of patients during electron beam therapy. This report discusses the anesthetic management of ten children undergoing IORT. With adequate preparation and interdepartmental communication, complications can be avoided during these challenging cases.

Friesen, R.H.; Morrison, J.E. Jr.; Verbrugge, J.J.; Daniel, W.E.; Aarestad, N.O.; Burrington, J.D.

1987-06-01

94

Radiation therapy for resistant sternal hydatid disease.  

PubMed

Hydatid disease is a zoonotic infectious disease for which there are known treatment procedures and effective antibiotics; however, there are resistant cases that do not respond to medication or surgery. We report a case diagnosed as hydatid disease of the chest wall and treated with radiation therapy (RT) after medical and surgical therapy had failed. In conclusion, RT represents an alternative treatment modality in resistant cases. PMID:23604185

Ulger, S; Barut, H; Tunc, M; Aydin, E; Ayd?nkarahalilo?lu, E; Gokcek, A; Karao?lano?lu, N

2013-04-20

95

Effects of radiation therapy in microvascular anastomoses  

SciTech Connect

The otolaryngologist, as a head and neck surgeon, commonly cares for patients with upper aerodigestive tract malignancies. Therapy of these neoplasms often requires wide excision. One standard reconstructive procedure utilizes pedicled regional flaps, both dermal and myodermal which have some disadvantages. The shortcomings of these pedicled regional flaps have led to the use of the vascularized free flap in certain cases. The occasional case may lead to catastrophe if microanastomoses fail when combined with radiation. Notwithstanding, many surgical series have reported success when radiation has been given. The present investigation was undertaken to assess the effects of radiation therapy on microvascular anastomoses when radiation is administered pre- or postoperatively or when nonradiated tissue is transferred to an irradiated recipient site. These effects were observed serially in an experimental rat model using a tubed superficial epigastric flap that adequately reflected tissue viability and vascular patency. The histologic changes were then noted over a three month period after completion of both radiation and surgery. This study adds credence to the observation of the lack of deleterious effects of radiation on experimental microvascular anastomotic patency whether the radiation is given before or after surgery or if radiated tissue is approximated to nonradiated vessels.

Fried, M.P.

1985-07-01

96

Focal Therapy, Differential Therapy, and Radiation Treatment for Prostate Cancer  

PubMed Central

Focal and differential therapy represent an approach to improve the therapeutic ratio of prostate cancer treatments. This concept is a shift from treating the whole gland to intensely treating the portion of the gland that contains significant tumor. However, there are many challenges in the move towards focal approaches. Defining which patients are suitable candidates for focal therapy approaches is an area of significant controversy, and it is likely that additional data from imaging or detailed biopsy methods is needed in addition to traditional risk factors. A number of methods have been suggested, and imaging with multiparametric MRI and transperineal template mapping biopsy have shown promise. The approach of differential therapy where the entire prostate is treated to a lower intensity and the tumor areas to high intensity is also discussed in detail. Radiation therapy is a well suited modality for the delivery of differential therapy. Data in the literature using external beam radiation, high dose rate brachytherapy, and low-dose rate brachytherapy for differential therapy are reviewed. Preliminary results are encouraging, and larger studies and randomized controlled trials are needed to validate this approach.

Jain, Anudh K.; Ennis, Ronald D.

2012-01-01

97

Effects of Prolonged Intensive Lipid-Lowering Therapy on the Characteristics of Carotid Atherosclerotic Plaques In Vivo by MRI A Case-Control Study  

Microsoft Academic Search

High-resolution magnetic resonance imaging (MRI) with flow suppression not only provides useful information on luminal and wall areas of the carotid artery but also can identify the principal tissue components of the carotid atherosclerotic plaque. The effects of intensive lipid-lowering therapy on these MRI tissue characteristics were examined in patients with coronary disease (CAD). Eight CAD patients who have been

Xue-Qiao Zhao; Chun Yuan; Thomas S. Hatsukami; Ellen Huss Frechette; Xiao-Jian Kang; Kenneth R. Maravilla; B. Greg Brown

98

The Accumulation of Protoporphyrin IX in Plaque Psoriasis After Topical Application of 5-Aminolevulinic Acid Indicates a Potential for Superficial Photodynamic Therapy  

Microsoft Academic Search

The success reported for the treatment of superficial skin carcinomas by photodynamic therapy with topical application of the photosensitizer precursor 5-aminolevulinic acid has therapeutic implications for the treatment of other skin disorders. This paper describes the accumulation of the photosensitizing agent protoporphyrin IX in areas of plaque psoriasis by monitoring of the fluorescence emission induced by low-intensity laser excitation at

Mark R. Stringer; Paul Collins; Dominic J. Robinson; Graeme I. Stables; Robert A. Sheehan-Dare

1996-01-01

99

Improved iodine-125 plaque design in the treatment of choroidal malignant melanoma.  

PubMed Central

The use and development of iodine-125 plaque therapy for choroidal malignant melanoma are described. Since 1975 experience has led to changes in plaque design and insertion techniques. Twenty-one patients were irradiated with local episcleral iodine-125 plaques. Three patients required a second plaque for tumour recurrence. Four eyes were enucleated because of continued tumour growth and a further eye was removed because of glaucoma secondary to radiation retinopathy. Two patients (9.5%) died of metastases. The remaining 19 patients are alive and clinically clear of metastases, with a mean follow up time of 73.1 months (range 43-142 months).

Hill, J C; Sealy, R; Shackleton, D; Stannard, C; Korrubel, J; Hering, E; Loxton, C

1992-01-01

100

Process of Coping with Radiation Therapy.  

ERIC Educational Resources Information Center

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

Johnson, Jean E.; And Others

1989-01-01

101

Radiation and the microenvironment tumorigenesis and therapy  

Microsoft Academic Search

Radiation rapidly and persistently alters the soluble and insoluble components of the tissue microenvironment. This affects the cell phenotype, tissue composition and the physical interactions and signalling between cells. These alterations in the microenvironment can contribute to carcinogenesis and alter the tissue response to anticancer therapy. Examples of these responses and their implications are discussed with a view to therapeutic

Catherine Park; Eric G. Wright; Mary Helen Barcellos-Hoff

2005-01-01

102

The Indiana University proton radiation therapy project  

Microsoft Academic Search

A fixed horizontal beam line at the Indiana University cyclotron facility (IUCF) has been equipped for proton radiation therapy treatment of head, neck, and brain tumors. The complete system will be commissioned and ready to treat patients early in 1993. IUCF can produce external proton beams from 45 to 200 MeV in energy, which corresponds to a maximum range in

C. Bloch; V. Derenchuk; J. Cameron; M. Fasano; J. Gilmore; R. Hashemian; N. Hornback; D. A. Low; J. Morphis; C. Peterson; D. Rosselot; G. Sandison; R.-N. Shen; H. Shidnia

1993-01-01

103

Glossodynia after radiation therapy and chemotherapy  

SciTech Connect

Radiation therapy and chemotherapy have decreased the mortality rates of cancer patients, but the morbidity associated with oral complications is high in many cases. A pretreatment oral evaluation and institution of a preventive care program reduce oral symptoms such as glossodynia considerably. When oral symptoms are minimized, the dentist can improve the patient's quality of life.40 references.

Naylor, G.D.; Marino, G.G.; Shumway, R.C.

1989-10-01

104

Role of radiation therapy in gastric adenocarcinoma  

Microsoft Academic Search

Outcomes in patients with gastric cancer in the United States remain disappointing, with a five-year overall survival rate of approximately 23%. Given high rates of local-regional control following surgery, a strong rationale exists for the use of adjuvant radiation therapy. Randomized trials have shown superior local control with adjuvant radiotherapy and improved overall survival with adjuvant chemoradiation. The benefi t

Lisa Hazard; John O'Connor; Courtney Scaife

105

Anesthesia for pediatric external beam radiation therapy  

Microsoft Academic Search

Background: For very young patients, anesthesia is often required for radiotherapy. This results in multiple exposures to anesthetic agents over a short period of time. We report a consecutive series of children anesthetized for external beam radiation therapy (EBRT).Methods: Five hundred twelve children ? 16 years old received EBRT from January 1983 to February 1996. Patient demographics, diagnosis, anesthesia techniques,

Jennifer T Fortney; Edward C Halperin; Caryn M Hertz; Scott R Schulman

1999-01-01

106

Optimization of external beam radiation therapy  

Microsoft Academic Search

A criterion for optimal external beam radiation therapy and a method for generating the associated optimal dose distributions are presented. The optimal beam configuration is defined to be the one with a dose distribution which provides the best ''least-squares fit'' to the prescribed tumor contour, subject to constraints on the dose at nearby vulnerable sites. A FORTRAN program for the

Stanley C. McDonald; Philip Rubin

1977-01-01

107

Process of Coping with Radiation Therapy.  

ERIC Educational Resources Information Center

|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

Johnson, Jean E.; And Others

1989-01-01

108

Comparing Radiation Therapies for Prostate Cancer  

Cancer.gov

In this trial, men with favorable-risk, localized prostate cancer will be randomly assigned to receive conventionally fractionated radiation therapy over the course of about eight weeks (41 daily treatments) or hypofractionated radiotherapy over a five-and-a-half week period (28 daily treatments).

109

Radiation therapy for orbital lymphoma  

SciTech Connect

Purpose: To describe radiation techniques and evaluate outcomes for orbital lymphoma. Methods and Materials: Forty-six patients (and 62 eyes) with orbital lymphoma treated with radiotherapy between 1987 and 2003 were included. The majority had mucosa-associated lymphoid tissue (48%) or follicular (30%) lymphoma. Seventeen patients had prior lymphoma at other sites, and 29 had primary orbital lymphoma. Median follow-up was 46 months. Results: The median dose was 30.6 Gy; one-third received <30 Gy. Electrons were used in 9 eyes with disease confined to the conjunctiva or eyelid, and photons in 53 eyes with involvement of intraorbital tissues to cover entire orbit. Local control rate was 98% for all patients and 100% for those with indolent lymphoma. Three of the 26 patients with localized primary lymphoma failed distantly, resulting in a 5-year freedom-from-distant-relapse rate of 89%. The 5-year disease-specific and overall survival rates were 95% and 88%, respectively. Late toxicity was mainly cataract formation in patients who received radiation without lens block. Conclusions A dose of 30 Gy is sufficient for indolent orbital lymphoma. Distant relapse rate in patients with localized orbital lymphoma was lower than that reported for low-grade lymphoma presenting in other sites. Orbital radiotherapy can be used for salvage of recurrent indolent lymphoma.

Zhou Ping [Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA (United States)]. E-mail: pzhou@partners.org; Ng, Andrea K. [Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA (United States); Silver, Barbara [Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA (United States); Li Sigui [Department of Biostatistical Sciences, Dana-Farber Cancer Institute, Boston, MA (United States); Hua Ling [Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA (United States); Mauch, Peter M. [Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA (United States)

2005-11-01

110

Radiation Therapy -- What It Is, How It Helps  

MedlinePLUS

... saved articles window. My Saved Articles My ACS Radiation Therapy -- What It Is, How It Helps Download Printable ... to-read guide offers a basic explanation of radiation therapy. Click on the topics below to get started. ...

111

Radiation Therapy and You: Support for People with Cancer  

MedlinePLUS

... Trials Cancer Statistics Research & Funding News About NCI Radiation Therapy and You: Support for People With Cancer In English En espaol Posted: 04/20/2007 Radiation Therapy and You About This Book Questions and Answers ...

112

External and internal radiation therapy: past and future directions.  

PubMed

Cancer is a leading cause of morbidity and mortality in the modern world. Treatment modalities comprise radiation therapy, surgery, chemotherapy and hormonal therapy. Radiation therapy can be performed by using external or internal radiation therapy. However, each method has its unique properties which undertakes special role in cancer treatment, this question is brought up that: For cancer treatment, whether external radiation therapy is more efficient or internal radiation therapy one? To answer this question, we need to consider principles and structure of individual methods. In this review, principles and application of each method are considered and finally these two methods are compared with each other. PMID:21119247

Sadeghi, Mahdi; Enferadi, Milad; Shirazi, Alireza

113

Comparison of particle-radiation-therapy modalities  

SciTech Connect

The characteristics of dose distribution, beam alignment, and radiobiological advantages accorded to high LET radiation were reviewed and compared for various particle beam radiotherapeutic modalities (neutron, Auger electrons, p, ..pi../sup -/, He, C, Ne, and Ar ions). Merit factors were evaluated on the basis of effective dose to tumor relative to normal tissue, linear energy transfer (LET), and dose localization, at depths of 1, 4, and 10 cm. In general, it was found that neutron capture therapy using an epithermal neutron beam provided the best merit factors available for depths up to 8 cm. The position of fast neutron therapy on the Merit Factor Tables was consistently lower than that of other particle modalities, and above only /sup 60/Co. The largest body of clinical data exists for fast neutron therapy; results are considered by some to be encouraging. It then follows that if benefits with fast neutron therapy are real, additional gains are within reach with other modalities.

Fairchild, R.G.; Bond, V.P.

1981-01-01

114

Pulsed laser radiation therapy of skin tumors  

SciTech Connect

Radiation from a neodymium laser was used to treat 846 patients with 687 precancerous lesions or benign tumors of the skin, 516 cutaneous carcinomas, 33 recurrences of cancer, 51 melanomas, and 508 metastatic melanomas in the skin. The patients have been followed for three months to 6.5 years. No relapses have been observed during this period. Metastases to regional lymph nodes were found in five patients with skin melanoma. Pulsed laser radiation may be successfully used in the treatment of precancerous lesions and benign tumors as well as for skin carcinoma and its recurrences, and for skin melanoma. Laser radiation is more effective in the treatment of tumors inaccessible to radiation therapy and better in those cases in which surgery may have a bad cosmetic or even mutilating effect. Laser beams can be employed in conjunction with chemo- or immunotherapy.

Kozlov, A.P.; Moskalik, K.G.

1980-11-15

115

Magnetically scanned ion beams for radiation therapy  

SciTech Connect

The advantageous physical characteristics of slowing-down and stopping charged particle ion beams have been demonstrated to be highly desirable for application to radiation therapy. Specifically, the prospect of concentrating the dose delivered into a sharp-defined treatment volume while keeping to a minimum the total dose to tissues outside this volume is most appealing, offering very significant improvements over what is possible with established radiation therapy techniques. Key to achieving this physical dose distribution in an actual treatment setting is the technique used for delivering the beam into the patient. Magnetically scanned beams are emerging as the technique of choice, but daunting problems remain still in achieving the utmost theoretically possible dose distributions. 21 refs., 2 figs.

Alonso, J.R.

1988-10-01

116

Prostatic carcinoma: rectal bleeding after radiation therapy  

Microsoft Academic Search

A 64-year-old man had a prostatic nodule on routine physical examination; per-rectal needle biopsies revealed a single focus of well differentiated adenocarcinoma. The patient had no history of urinary obstruction or of bowel difficulties. Accordingly, this was clinical stage II carcinoma of the prostate. The patient chose to receive external radiation therapy and was given small-field rotational treatment to a

A. R. Kagan; R. J. Steckel

1981-01-01

117

Androgen deprivation with radiation therapy compared with radiation therapy alone for locally advanced prostatic carcinoma: a randomized comparative trial of the radiation therapy oncology group  

Microsoft Academic Search

ObjectivesAndrogen deprivation therapy before and during radiation therapy could, by reducing tumor volume, increase local tumor control, disease-free survival, and overall survival in patients with locally advanced adenocarcinomas of the prostate.

Miljenko V. Pilepich; William T. Sause; William U. Shipley; John M. Krall; Colleen A. Lawton; David Grignon; Muhyi Al-Sarraf; Ross A. Abrams; Richard Caplan; Madhu J. John; Marvin Rotman; James D. Cox; R. L. Scotte Doggett; Philip Rubin; Mark S. Soloway

1995-01-01

118

Automatic field shaping for conformal radiation therapy.  

PubMed

A computer method has been developed to shape the radiation field to conform to the shape of the target as visualized through the beam's eye view (BEV) perspective for conformal radiation therapy. Initially, a series of 2D target contours to define the target size are input into the computer. These target contour data are mapped onto a 3D surface and thereafter projected onto a BEV plane. The projection's outer boundary of the target is auto-contoured. After auto-contouring, a margin is automatically added to define the radiation beam cross section. Since the BEV plane is arbitrarily oriented about the target, the beam orientation can be non-coplanar to the plane of the target contours. For a chosen beam orientation, the conformal treatment beam cross section can be generated automatically using this computer technique and output to either a laser printer, a plotter or stored on files for transfer to the linear accelerator computer system. PMID:7924269

Ayyangar, K

1994-04-01

119

Sphenoid Wing en plaque meningiomas: Surgical results and recurrence rates  

PubMed Central

Background: Sphenoid wing en plaque meningiomas are a subgroup of meningiomas defined by its particular sheet-like dural involvement and its disproportionately large bone hyperostosis. En plaque meningiomas represent 2-9% of all meningiomas and they are mainly located in the sphenoid wing. Total surgical resection is difficult and therefore these tumors have high recurrence rates. Methods: Eighteen patients with sphenoid wing en plaque meningiomas surgically treated between January 1998 and December 2008 were included. Clinical, surgical, and follow-up data were retrospectively analyzed. Results: Mean age was 52.2 years and 83% were female. Five patients presented extension of dural component into the orbit and six patients presented cavernous sinus infiltration. Adjuvant radiation therapy was performed in three patients. After a mean follow-up of 4.6 years, five patients developed tumor recurrence - two patients were submitted to surgical treatment and the other three were submitted to radiation therapy. No patient presented recurrence after radiation therapy, whether performed immediately in the postoperative period or performed after recurrence. Patients without tumor extension to cavernous sinus or orbital cavity have the best prognosis treated with surgery alone. When tumor extension involves these locations the recurrence rate is high, especially in cases not submitted to adjuvant radiation therapy. Conclusion: Cavernous sinus and superior orbital fissure involvement are frequent and should be considered surgical limits. Postoperative radiation therapy is indicated in cases with residual tumor in these locations.

Simas, Nuno M.; Farias, Joao Paulo

2013-01-01

120

The Evolving Role of Radiation Therapy in the Management of Malignant Melanoma  

PubMed Central

The incidence of melanoma is rising in the United States, leading to an estimated 68,720 new diagnoses and 8,650 deaths. The natural history involves metastases to lymph nodes, lung, liver, brain, and often to other sites. Primary treatment for melanoma is surgical excision of the primary tumor and affected lymph nodes. The role of adjuvant or definitive radiation therapy in the treatment of melanoma remains controversial, as melanoma has traditionally been viewed as a prototypical radioresistant cancer. However, recent studies suggest that under certain clinical circumstances, there may be a significant role for radiation therapy in melanoma treatment. Stereotactic radiosurgery for brain metastases has shown effective local control. High dose per fraction radiation therapy has been associated with a lower rate of locoregional recurrence of sinonasal melanoma. Plaque brachytherapy has evolved into a promising alternative to enucleation at the expense of moderate reduction in visual acuity. Adjuvant radiation therapy following lymphadenectomy in node positive melanoma prevents local and regional recurrence. The newer clinical data along with emerging radiobiological data indicate that radiotherapy is likely to play a greater role in melanoma management, and should be considered as a treatment option.

Khan, Niloufer; Khan, Mohammad K.; Almasan, Alex; Singh, Arun D.; Macklis, Roger

2011-01-01

121

The Evolving Role of Radiation Therapy in the Management of Malignant Melanoma  

SciTech Connect

The incidence of melanoma is rising in the United States, leading to an estimated 68,720 new diagnoses and 8,650 deaths annually. The natural history involves metastases to lymph nodes, lung, liver, brain, and often to other sites. Primary treatment for melanoma is surgical excision of the primary tumor and affected lymph nodes. The role of adjuvant or definitive radiation therapy in the treatment of melanoma remains controversial, because melanoma has traditionally been viewed as a prototypical radioresistant cancer. However, recent studies suggest that under certain clinical circumstances, there may be a significant role for radiation therapy in melanoma treatment. Stereotactic radiosurgery for brain metastases has shown effective local control. High dose per fraction radiation therapy has been associated with a lower rate of locoregional recurrence of sinonasal melanoma. Plaque brachytherapy has evolved into a promising alternative to enucleation at the expense of moderate reduction in visual acuity. Adjuvant radiation therapy following lymphadenectomy in node-positive melanoma prevents local and regional recurrence. The newer clinical data along with emerging radiobiological data indicate that radiotherapy is likely to play a greater role in melanoma management and should be considered as a treatment option.

Khan, Niloufer [Case Western Reserve University School of Medicine, Cleveland, OH (United States); Khan, Mohammad K., E-mail: drkhurram2000@gmail.com [Taussig Cancer Institute, Lerner College of Medicine and Cole Eye Institute, Cleveland Clinic, Cleveland, OH (United States); Almasan, Alex; Singh, Arun D.; Macklis, Roger [Taussig Cancer Institute, Lerner College of Medicine and Cole Eye Institute, Cleveland Clinic, Cleveland, OH (United States)

2011-07-01

122

Outcome of Radiation Therapy Patients Perception of Benefit of Medical Nutrition Therapy Received During Treatment  

Microsoft Academic Search

LEARNING OUTCOME: To describe the benefits perceived by radiation therapy patients of Medical Nutrition Therapy.The satisfaction and benefit that radiation therapy patients perceived from Medical Nutrition Therapy was studied. Seventy-two patients undergoing radiation therapy for lung, cervical, esophageal, prostate, and head and neck cancer from 19921995 were surveyed. Patients met with a Registered Dietitian for a minimum of two visits

C. G. Polisena

1997-01-01

123

Intensity-Modulated Radiation Therapy, Proton Therapy, or Conformal Radiation Therapy and Morbidity and Disease Control in Localized Prostate Cancer  

PubMed Central

Context There has been rapid adoption of newer radiation treatments such as intensitymodulated radiation therapy (IMRT) and proton therapy despite greater cost and limited demonstrated benefit compared with previous technologies. Objective To determine the comparative morbidity and disease control of IMRT, proton therapy, and conformal radiation therapy for primary prostate cancer treatment. Design, Setting, and Patients Population-based study using Surveillance, Epidemiology, and End ResultsMedicare-linked data from 2000 through 2009 for patients with nonmetastatic prostate cancer. Main Outcome Measures Rates of gastrointestinal and urinary morbidity, erectile dysfunction, hip fractures, and additional cancer therapy. Results Use of IMRT vs conformal radiation therapy increased from 0.15% in 2000 to 95.9% in 2008. In propensity scoreadjusted analyses (N=12 976), men who received IMRT vs conformal radiation therapy were less likely to receive a diagnosis of gastrointestinal morbidities (absolute risk, 13.4 vs 14.7 per 100 person-years; relative risk [RR], 0.91; 95% CI, 0.860.96) and hip fractures (absolute risk, 0.8 vs 1.0 per 100 person-years; RR, 0.78; 95% CI, 0.650.93) but more likely to receive a diagnosis of erectile dysfunction (absolute risk, 5.9 vs 5.3 per 100 person-years; RR, 1.12; 95% CI, 1.031.20). Intensitymodulated radiation therapy patients were less likely to receive additional cancer therapy (absolute risk, 2.5 vs 3.1 per 100 person-years; RR, 0.81; 95% CI, 0.730.89). In a propensity scorematched comparison between IMRT and proton therapy (n=1368), IMRT patients had a lower rate of gastrointestinal morbidity (absolute risk, 12.2 vs 17.8 per 100 person-years; RR, 0.66; 95% CI, 0.550.79). There were no significant differences in rates of other morbidities or additional therapies between IMRT and proton therapy. Conclusions Among patients with nonmetastatic prostate cancer, the use of IMRT compared with conformal radiation therapy was associated with less gastrointestinal morbidity and fewer hip fractures but more erectile dysfunction; IMRT compared with proton therapy was associated with less gastrointestinal morbidity.

Sheets, Nathan C.; Goldin, Gregg H.; Meyer, Anne-Marie; Wu, Yang; Chang, YunKyung; Sturmer, Til; Holmes, Jordan A.; Reeve, Bryce B.; Godley, Paul A.; Carpenter, William R.; Chen, Ronald C.

2013-01-01

124

Role of radiation therapy in Hodgkin's lymphoma.  

PubMed

Radiation therapy was the first modality that solely cured patients with Hodgkin's lymphoma (HL) as early as the 1940s. In the absence of other curative options, the radiation field in full dose was extended to encompass both involved and uninvolved sites including many normal organs. Decades later, it was evident that some of the HL survivors succumbed to radiation-related effects, mostly second solid tumors. The more recent reliance on modern chemotherapy in combination with radiation yielded further improvement in disease control and allowed a marked reduction in radiation exposure. Some oncologists even suggested that chemotherapy alone might retain the excellent results obtained with combined modality and campaigned for the exclusion of radiotherapy from the treatment program. However, analysis of randomized studies (as discussed later) supports the inclusion of reduced-field and dose radiotherapy in treatment programs for HL. Furthermore, new concerns regarding the short- and long-term safety of enhancing chemotherapy to compensate for the omission of radiotherapy favor shorter courses of chemotherapy. Short chemotherapy supplemented with mini-radiotherapy constitutes a highly effective and safe treatment of HL, particularly in early stages. PMID:19390312

Yahalom, Joachim

125

Intraoperative radiation therapy in recurrent ovarian cancer  

SciTech Connect

Purpose: To evaluate disease outcomes and complications in patients with recurrent ovarian cancer treated with cytoreductive surgery and intraoperative radiation therapy (IORT). Methods and Materials: A retrospective study of 24 consecutive patients with ovarian carcinoma who underwent secondary cytoreduction and intraoperative radiation therapy at our institution between 1994 and 2002 was conducted. After optimal cytoreductive surgery, IORT was delivered with orthovoltage X-rays (200 kVp) using individually sized and beveled cone applications. Outcomes measures were local control of disease, progression-free interval, overall survival, and treatment-related complications. Results: Of these 24 patients, 22 were available for follow-up analysis. Additional treatment at the time of and after IORT included whole abdominopelvic radiation, 9; pelvic or locoregional radiation, 5; chemotherapy, 6; and no adjuvant treatment, 2. IORT doses ranged from 9-14 Gy (median, 12 Gy). The anatomic sites treated were pelvis (sidewalls, vaginal cuff, presacral area, anterior pubis), para-aortic and paracaval lymph node beds, inguinal region, or porta hepatitis. At a median follow-up of 24 months, 5 patients remain free of disease, whereas 17 patients have recurred, of whom 4 are alive with disease and 13 died from disease. Five patients recurred within the radiation fields for a locoregional relapse rate of 32% and 12 patients recurred at distant sites with a median time to recurrence of 13.7 months. Five-year overall survival was 22% with a median survival of 26 months from time of IORT. Nine patients (41%) experienced Grade 3 toxicities from their treatments. Conclusion: In carefully selected patients with locally recurrent ovarian cancer, combined IORT and tumor reductive surgery is reasonably tolerated and may contribute to achieving local control and disease palliation.

Yap, O.W. Stephanie [Division of Gynecologic Oncology, Department of Gynecology and Obstetrics, Stanford University School of Medicine, Stanford, CA (United States)]. E-mail: stbeast@stanford.edu; Kapp, Daniel S. [Division of Radiation Therapy, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); Teng, Nelson N.H. [Division of Gynecologic Oncology, Department of Gynecology and Obstetrics, Stanford University School of Medicine, Stanford, CA (United States); Husain, Amreen [Division of Gynecologic Oncology, Department of Gynecology and Obstetrics, Stanford University School of Medicine, Stanford, CA (United States)

2005-11-15

126

Optical Tracking Technology in Stereotactic Radiation Therapy  

SciTech Connect

The last decade has seen the introduction of advanced technologies that have enabled much more precise application of therapeutic radiation. These relatively new technologies include multileaf collimators, 3-dimensional conformal radiotherapy planning, and intensity modulated radiotherapy in radiotherapy. Therapeutic dose distributions have become more conformal to volumes of disease, sometimes utilizing sharp dose gradients to deliver high doses to target volumes while sparing nearby radiosensitive structures. Thus, accurate patient positioning has become even more important, so that the treatment delivered to the patient matches the virtual treatment plan in the computer treatment planning system. Optical and image-guided radiation therapy systems offer the potential to improve the precision of patient treatment by providing a more robust fiducial system than is typically used in conventional radiotherapy. The ability to accurately position internal targets relative to the linac isocenter and to provide real-time patient tracking theoretically enables significant reductions in the amount of normal tissue irradiated. This report reviews the concepts, technology, and clinical applications of optical tracking systems currently in use for stereotactic radiation therapy. Applications of radiotherapy optical tracking technology to respiratory gating and the monitoring of implanted fiducial markers are also discussed.

Wagner, Thomas H. [Department of Radiation Physics, M. D. Anderson Cancer Center Orlando, Orlando, FL (United States)]. E-mail: thomas.wagner@orhs.org; Meeks, Sanford L. [Department of Radiation Physics, M. D. Anderson Cancer Center Orlando, Orlando, FL (United States); Bova, Frank J. [Department of Neurological Surgery, University of Florida, Gainesville, FL (United States); Friedman, William A. [Department of Neurological Surgery, University of Florida, Gainesville, FL (United States); Willoughby, Twyla R. [Department of Radiation Physics, M. D. Anderson Cancer Center Orlando, Orlando, FL (United States); Kupelian, Patrick A. [Department of Radiation Physics, M. D. Anderson Cancer Center Orlando, Orlando, FL (United States); Tome, Wolfgang [Department of Human Oncology, University of Wisconsin, Madison, WI (United States)

2007-07-01

127

Application of Histogram Analysis in Radiation Therapy (HART) in Intensity Modulation Radiation Therapy (IMRT) Treatments  

Microsoft Academic Search

A carcinoma is a malignant cancer that emerges from epithelial cells in structures through out the body.It invades the critical organs, could metastasize or spread to lymph nodes.IMRT is an advanced mode of radiation therapy treatment for cancer. It delivers more conformal doses to malignant tumors sparing the critical organs by modulating the intensity of radiation beam.An automated software, HART

Anil Pyakuryal

2009-01-01

128

HYPERBARIC OXYGEN THERAPY FOR RADIATION INDUCED HEMORRHAGIC CYSTITIS  

Microsoft Academic Search

PurposeRadiation therapy has been used successfully to treat pelvic malignancy but morbidity from hemorrhagic cystitis remains a major long-term sequela in 1 to 2% of patients. Obliterative endarteritis secondary to ionizing radiation leads to tissue hypoxia and poor healing. Hyperbaric oxygen therapy has been demonstrated to improve angiogenesis and promote healing in radiation injured tissue, including the bladder. We describe

RANJIV MATHEWS; NATARAJAN RAJAN; LAURA JOSEFSON; ENRICO CAMPORESI; ZAHI MAKHULI

1999-01-01

129

Geant4 simulations for microbeam radiation therapy (MRT) dosimetry  

Microsoft Academic Search

Radiation therapy is one of the techniques most commonly used in the treatment of various types of tumors. The microbeam radiation therapy (MRT) is a very promising variant, which exploits the property that tissues can tolerate high doses of radiation in small volumes. The effectiveness of MRT is well represented by the peak-to-valley dose ratios (PVDRs), which are one of

J. Spiga; E. A. Siegbahn; E. Brauer-Krisch; P. Randaccio; A. Bravin

2007-01-01

130

New irradiation geometry for microbeam radiation therapy.  

PubMed

Microbeam radiation therapy (MRT) has the potential to treat infantile brain tumours when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of x-rays but provides unusual resistance to radioneurotoxicity, presumably from the migration of endothelial cells from 'valleys' into 'peaks', i.e., into directly irradiated microslices of tissues. We present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumour area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumouricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumour in the paths of the arrays. PMID:15972983

Bruer-Krisch, E; Requardt, H; Rgnard, P; Corde, S; Siegbahn, E; LeDuc, G; Brochard, T; Blattmann, H; Laissue, J; Bravin, A

2005-06-22

131

New irradiation geometry for microbeam radiation therapy  

NASA Astrophysics Data System (ADS)

Microbeam radiation therapy (MRT) has the potential to treat infantile brain tumours when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of x-rays but provides unusual resistance to radioneurotoxicity, presumably from the migration of endothelial cells from 'valleys' into 'peaks', i.e., into directly irradiated microslices of tissues. We present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumour area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumouricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumour in the paths of the arrays.

Bruer-Krisch, E.; Requardt, H.; Rgnard, P.; Corde, S.; Siegbahn, E.; LeDuc, G.; Brochard, T.; Blattmann, H.; Laissue, J.; Bravin, A.

2005-07-01

132

Prostatic carcinoma: rectal bleeding after radiation therapy  

SciTech Connect

A 64-year-old man had a prostatic nodule on routine physical examination; per-rectal needle biopsies revealed a single focus of well differentiated adenocarcinoma. The patient had no history of urinary obstruction or of bowel difficulties. Accordingly, this was clinical stage II carcinoma of the prostate. The patient chose to receive external radiation therapy and was given small-field rotational treatment to a dose of 7000 rad (70 Gy) at a rate of 800 rad (8 Gy) weekly. Late in treatment, he experienced transitory diarrhea with flatulence, but this cleared with completion of treatment. Twenty months later he began to note frequent soft bowel movements, occasionally with red blood. At sigmoidoscopy 24 months after completion of treatment, the rectal mucosa was noted to be friable with minimal bleeding, presumably the result of radiation proctitis.

Kagan, A.R.; Steckel, R.J. (eds.)

1981-06-01

133

What extent of radiation therapy is standard?  

PubMed

This review will address: (1) 'what are the current indications for radiation therapy (RT), following both mastectomy and breast-conserving surgery?' and (2) 'if RT is indicated, what are the appropriate volumes or 'targets' to be treated?' Given the complexity of these questions, this review will focus on selected topics considered of greatest current interest. In addition, this review will primarily focus on results obtained from randomized clinical trials (RCTs). Finally, we acknowledge an American point of view in our discussion. PMID:16236515

Bellon, Jennifer R; Harris, Jay R

2005-10-19

134

Particle Radiation Therapy for Gastrointestinal Malignancies  

PubMed Central

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.

Meyer, Jeffrey J.; Willett, Christopher G.

2007-01-01

135

Clinical applications of continuous infusion chemotherapy ahd concomitant radiation therapy  

SciTech Connect

This book presents information on the following topics: theoretical basis and clinical applications of 5-FU as a radiosensitizer; treatment of hepatic metastases from gastro intestingal primaries with split course radiation therapy; combined modality therapy with 5-FU, Mitomycin-C and radiation therapy for sqamous cell cancers; treatment of bladder carcinoma with concomitant infusion chemotherapy and irradiation; a treatment of invasiv bladder cancer by the XRT/5FU protocol; concomitant radiation therapy and doxorubicin by continuous infusion in advanced malignancies; cis platin by continuous infusion with concurrent radiation therapy in malignant tumors; combination of radiation with concomitant continuous adriamycin infusion in a patient with partially excised pleomorphic soft tissue sarcoma of the lower extremeity; treatment of recurrent carcinoma of the paranasal sinuses using concomitant infusion cis-platinum and radiation therapy; hepatic artery infusion for hepatic metastases in combination with hepatic resection and hepatic radiation; study of simultaneous radiation therapy, continuous infusion, 5FU and bolus mitomycin-C; cancer of the esophagus; continuous infusion VP-16, bolus cis-platinum and simultaneous radiation therapy as salvage therapy in small cell bronchogenic carcinoma; and concomitant radiation, mitomycin-C and 5-FU infusion in gastro intestinal cancer.

Rosenthal, C.J.; Rotman, M.

1986-01-01

136

Collimator design for experimental minibeam radiation therapy  

SciTech Connect

Purpose: To design and optimize a minibeam collimator for minibeam radiation therapy studies using a 250 kVp x-ray machine as a simulated synchrotron source. Methods: A Philips RT250 orthovoltage x-ray machine was modeled using the EGSnrc/BEAMnrc Monte Carlo software. The resulting machine model was coupled to a model of a minibeam collimator with a beam aperture of 1 mm. Interaperture spacing and collimator thickness were varied to produce a minibeam with the desired peak-to-valley ratio. Results: Proper design of a minibeam collimator with Monte Carlo methods requires detailed knowledge of the x-ray source setup. For a cathode-ray tube source, the beam spot size, target angle, and source shielding all determine the final valley-to-peak dose ratio. Conclusions: A minibeam collimator setup was created, which can deliver a 30 Gy peak dose minibeam radiation therapy treatment at depths less than 1 cm with a valley-to-peak dose ratio on the order of 23%.

Babcock, Kerry; Sidhu, Narinder; Kundapur, Vijayananda; Ali, Kaiser [Saskatoon Cancer Centre, 20 Campus Drive, Saskatoon, Saskatchewan S7N 4H4 (Canada)

2011-04-15

137

Stereotactic body radiation therapy for liver metastases.  

PubMed

Although resection is the standard of care for liver metastasis, 80-90% of patients are not resectable at diagnosis. Advances in combination chemotherapy, particularly with targeted agents, have increased tumour response and survival in patients with unresectable metastatic colorectal cancer, but these techniques have limitations and may be associated with high recurrence rates. Some autopsy series have shown that as many as 40% of patients with metastatic colorectal cancer have disease confined to the liver; aggressive local therapy may improve overall survival in such patients. Local control of liver metastases can also ease hepatic capsular pain to improve quality of life. Stereotactic body radiation therapy (SBRT) offers an alternative, non-invasive approach to the treatment of liver metastasis through precisely targeted delivery of radiation to the tumours while minimising normal tissue toxicity. Early applications of SBRT to liver metastases have been promising with the reports of 2-year local control rates of 71-86% and other studies reporting 18-month local control rates of 71-93%. While these data establish the safety of SBRT for liver metastases, more rigorous phase II clinical studies are needed to fully evaluate long-term efficacy and toxicity results. In the interim, this review stresses that SBRT of liver must be performed cautiously given the challenges of organ motion and the low toxicity tolerance of the surrounding hepatic parenchyma. PMID:19773153

Dawood, Omar; Mahadevan, Anand; Goodman, Karyn A

2009-09-19

138

Tissue biomarkers for prostate cancer radiation therapy.  

PubMed

Prostate cancer is the most common cancer and second leading cause of cancer deaths among men in the United States. Most men have localized disease diagnosed following an elevated serum prostate specific antigen test for cancer screening purposes. Standard treatment options consist of surgery or definitive radiation therapy directed by clinical factors that are organized into risk stratification groups. Current clinical risk stratification systems are still insufficient to differentiate lethal from indolent disease. Similarly, a subset of men in poor risk groups need to be identified for more aggressive treatment and enrollment into clinical trials. Furthermore, these clinical tools are very limited in revealing information about the biologic pathways driving these different disease phenotypes and do not offer insights for novel treatments which are needed in men with poor-risk disease. We believe molecular biomarkers may serve to bridge these inadequacies of traditional clinical factors opening the door for personalized treatment approaches that would allow tailoring of treatment options to maximize therapeutic outcome. We review the current state of prognostic and predictive tissue-based molecular biomarkers which can be used to direct localized prostate cancer treatment decisions, specifically those implicated with definitive and salvage radiation therapy. PMID:22292443

Tran, P T; Hales, R K; Zeng, J; Aziz, K; Salih, T; Gajula, R P; Chettiar, S; Gandhi, N; Wild, A T; Kumar, R; Herman, J M; Song, D Y; DeWeese, T L

2012-07-01

139

Scanning Ion Beams for Radiation Therapy  

NASA Astrophysics Data System (ADS)

Beams of light ions, ranging from proton to neon beams, are used for radiation therapy because they exhibit a well defined range in tissue (Bragg ionization curve) and suffer relatively little lateral scattering. An effective radiation dose can be delivered to the tumor while achieving optimal sparing of the surrounding normal tissues by scanning irregularly shaped target volumes laterally and in depth with a narrow pencil beam. Magnetic beam spreading methods, first introduced at LBL in order to minimize ion fragmentation, will be used at the Northeast Proton Therapy Center in Boston for maximizing the range of the proton beam. 3-D pencil beam scanning systems are being implemented at PSI, Switzerland, where a voxel scanning system has been installed for proton treatments and at GSI, Germany, where a raster scanner has been developed for carbon beams. For pencil beam scanning, patient safety and treatment time limitations impose stringent requirements on beam stability, intensity control, energy switching, and the control system. This work was supported by the U.S. Department of Energy under Contract No. DE-AC03-76SF00098, and in part by the National Institute of Health under Grant No. CA56932.

Ludewigt, Bernhard A.

1996-05-01

140

Dosimetry in modern radiation therapy: limitations and needs  

NASA Astrophysics Data System (ADS)

This paper extends the motivation for gel dosimetry beyond the discussion of solely radiation measurement and presents a broad review of the developments in modern conformal radiation therapy using intensity modulation, image guidance and adaptive processes.

Schreiner, L. John

2006-12-01

141

How Should I Care for Myself During Radiation Therapy?  

MedlinePLUS

... Prostate Skin Upper GI Latest Research Find a Radiation Oncologist Last Name: Facility: City: State: Zip Code: ... information How Should I Care for Myself During Radiation Therapy? Get plenty of rest. Many patients experience ...

142

Stereotactic body radiation therapy for lung cancer.  

PubMed

Lung cancer remains the leading cause of death worldwide. Because many patients with non-small cell lung cancer are elderly and have multiple comorbid conditions, many with potentially curable disease are unfit to undergo definitive surgical resection. Stereotactic body radiation therapy (SBRT) is increasingly being used to treat patients with medically inoperable stage I non-small cell lung cancer. SBRT combines reproducible and accurate anatomic targeting with the delivery of a very high dose per fraction of radiation to a target. Planning and delivery of SBRT is a coordinated effort between the radiation oncology team and consulting services. Clinical outcomes, toxicity profiles, treatment delivery, and indications for SBRT are reviewed. Services currently billed during planning and treatment of SBRT are detailed. This article introduces to consulting specialists and subspecialists a new Current Procedural Terminology code that has been proposed to more accurately reflect work performed during SBRT by these consulting providers. This code is described, and its implications for patient care are discussed. PMID:23732589

Simone, Charles B; Wildt, Brian; Haas, Andrew R; Pope, Greg; Rengan, Ramesh; Hahn, Stephen M

2013-06-01

143

Effectiveness of Conventional Drug Therapy of Plaque Psoriasis in the Context of Consensus Guidelines: A Prospective Observational Study in 150 Patients  

PubMed Central

Background Evidence for superior outcome by adhering to therapy guidelines is imperative to their acceptance and adaptation for the optimal management of disease variants. Objective Comparative study of prospective outcomes in simultaneous consideration of independent variables in groups of 150 patients of plaque psoriasis either treated adhering to or in digression of standard guidelines. Methods The psoriasis area severity index (PASI) and the dermatology life quality index (DLQI), prior to and after three months of uninterrupted therapy were examined in treatment groups among 150 patients. Recovery rates of 75% or more in PASI were compared. Independent variables were also examined for their bearing on the outcome. Results The vast majority was early onset disease phenotype. All three treatment regimens when administered in adherence to the guidelines yielded significantly superior rates of defined recovery both in PASI and DLQI. Compromise of the therapeutic outcome appeared in high stress profiles, obesity, female sex and alcohol, tobacco or smoking habit. Conclusion Conventional drug therapy of plaque psoriasis yields superior outcome by adhering to the consensus guidelines. Psychiatric address to stress must be integral and special considerations for phenotypic/syndromic variants is emphasized for effective therapy of psoriasis.

Gupta, Ashok Kumar; Pandey, Shyam Sunder

2013-01-01

144

Heavy-ion sources for radiation therapy  

NASA Astrophysics Data System (ADS)

The usefulness of particle beams for radiation therapy has been well and widely recognized. For the cure of cancer patients, many accelerator facilities have already been utilized, and some new facilities are now being put into operation, or are under construction. Considering the medical and biological requirements, light heavy ions with an energy of several hundred MeV/nucleon are regarded as being the most suitable species. A reasonable choice to this end is an accelerator complex, for an example, one comprising an ion source, an injector linac, and a synchrotron. The ion source is of great importance, since its characteristics strongly affect the overall performance of the accelerator system. A pulsed Penning source (PIGIS) has been successfully used at Lawrence Berkeley Laboratory. Recently, at the National Institute of Radiological Sciences a low-duty pulsed PIGIS for the heavy-ion medical accelerator in Chiba (HIMAC) has been developed; it has both a long lifetime and a high peak intensity. As other types of ion sources, an electron-beam ion source (EBIS) and an electron-cyclotron-resonance ion source (ECRIS) are being developed at several laboratories. An EBIS is basically a pulsed source, and is being successfully used at Saclay. By using an after-glow mode, two ECRISs have made remarkable progress at Grenoble and the Grand Accelerateur National d'Ions Lourds; similar tests are proceeding for the Schwer-Ionen Synchrotron at the Gesellschaft for Schwer-Ionenforschung, the booster at Centre d'Europeen de Recherche Nucleaire, and the HIMAC. These different types of heavy-ion sources are discussed from the viewpoint of their application to radiation therapy.

Sato, Y.; Kitagawa, A.; Ogawa, H.; Yamada, S.

1994-10-01

145

Radiation therapy for primary vaginal carcinoma  

PubMed Central

Brachytherapy plays a significant role in the management of cervical cancer, but the clinical significance of brachytherapy in the management of vaginal cancer remains to be defined. Thus, a single institutional experience in the treatment of primary invasive vaginal carcinoma was reviewed to define the role of brachytherapy. We retrospectively reviewed the charts of 36 patients with primary vaginal carcinoma who received definitive radiotherapy between 1992 and 2010. The treatment modalities included high-dose-rate intracavitary brachytherapy alone (HDR-ICBT; two patients), external beam radiation therapy alone (EBRT; 14 patients), a combination of EBRT and HDR-ICBT (10 patients), or high-dose-rate interstitial brachytherapy (HDR-ISBT; 10 patients). The median follow-up was 35.2 months. The 2-year local control rate (LCR), disease-free survival (DFS), and overall survival (OS) were 68.8%, 55.3% and 73.9%, respectively. The 2-year LCR for Stage I, II, III and IV was 100%, 87.5%, 51.5% and 0%, respectively (P = 0.007). In subgroup analysis consisting only of T2T3 disease, the use of HDR-ISBT showed marginal significance for favorable 5-year LCR (88.9% vs 46.9%, P = 0.064). One patient each developed Grade 2 proctitis, Grade 2 cystitis, and a vaginal ulcer. We conclude that brachytherapy can play a central role in radiation therapy for primary vaginal cancer. Combining EBRT and HDR-ISBT for T2T3 disease resulted in good local control.

Murakami, N.; Kasamatsu, T.; Sumi, M.; Yoshimura, R.; Takahashi, K.; Inaba, K.; Morota, M.; Mayahara, H.; Ito, Y.; Itami, J.

2013-01-01

146

Radiation therapy for primary vaginal carcinoma.  

PubMed

Brachytherapy plays a significant role in the management of cervical cancer, but the clinical significance of brachytherapy in the management of vaginal cancer remains to be defined. Thus, a single institutional experience in the treatment of primary invasive vaginal carcinoma was reviewed to define the role of brachytherapy. We retrospectively reviewed the charts of 36 patients with primary vaginal carcinoma who received definitive radiotherapy between 1992 and 2010. The treatment modalities included high-dose-rate intracavitary brachytherapy alone (HDR-ICBT; two patients), external beam radiation therapy alone (EBRT; 14 patients), a combination of EBRT and HDR-ICBT (10 patients), or high-dose-rate interstitial brachytherapy (HDR-ISBT; 10 patients). The median follow-up was 35.2 months. The 2-year local control rate (LCR), disease-free survival (DFS), and overall survival (OS) were 68.8%, 55.3% and 73.9%, respectively. The 2-year LCR for Stage I, II, III and IV was 100%, 87.5%, 51.5% and 0%, respectively (P = 0.007). In subgroup analysis consisting only of T2-T3 disease, the use of HDR-ISBT showed marginal significance for favorable 5-year LCR (88.9% vs 46.9%, P = 0.064). One patient each developed Grade 2 proctitis, Grade 2 cystitis, and a vaginal ulcer. We conclude that brachytherapy can play a central role in radiation therapy for primary vaginal cancer. Combining EBRT and HDR-ISBT for T2-T3 disease resulted in good local control. PMID:23559599

Murakami, N; Kasamatsu, T; Sumi, M; Yoshimura, R; Takahashi, K; Inaba, K; Morota, M; Mayahara, H; Ito, Y; Itami, J

2013-04-04

147

Ghrelin as a Novel Therapy for Radiation Combined Injury  

PubMed Central

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.

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

2010-01-01

148

Exclusive plaque psoriasis of the lips: efficacy of combination therapy of topical tacrolimus, calcipotriol, and betamethasone dipropionate.  

PubMed

A 16-year-old unmarried woman presented with recurrent cracking of the lips indicated by the appearance of grayish white flakes since October 2004, which, in due course, shed off leaving behind an apparently normal mucous membrane. Chewing roasted corn treated with salt and lemon (bhutta) initially caused the lesions. Ever since, it has been a cause of its exacerbation. She never had any relief with either systemic or topical treatment. In fact, an obsession had overtaken her, resulting in a psychological setback. She denied regular drug use for any other ailment. Her menstrual cycle was normal. There was a positive history of psoriasis in her mother. Examination of the lips was conspicuous. It was marked by the presence of a well-circumscribed, moist, raised plaque (Figure 1). Its surface was irregular, with elevation and depression. It was made up of thick, grayish white scales, which were arranged in layers; however, Grattage/Auspitz sign could not be elicited. Fissuring was prominent but the buccal mucosa, surface of the tongue, gingiva, and palate were normal. The clinical examination did not reveal any evidence of skin and/or nail psoriasis/psoriatic arthropathy or any other systemic abnormality. Blood examination including total and differential leukocyte count, complete hemogram, and liver and renal function tests were normal. Biopsy of the representative lesion was subjected to serial sections. They were stained with hematoxylin-eosin to work up microscopic pathology. It revealed the presence of mounds of parakeratosis with numerous neutrophilic Munro microabscesses (Figure 2). Submucosal vessels were dilated and congested. Periodic-acid-Schiff (PAS) stain revealed fungal hyphae and spores within the parakeratotic layer. Colonies of Gram-positive cocci were also demonstrated on the surface of the mucosa. She was administered combination therapy, comprising topical tacrolimus (0.1%) ointment and calcipotirol hydrate (50 microg/g) plus betmethasone dipropionate (0.5 mg/g) twice a day for 7 days. A single bolus dose of fluconazole 450 mg orally was also administered. The response to treatment was favorable and the lesions showed regression (Figure 3). PMID:22779103

Sehgal, Virendra N; Sehgal, Shruti; Verma, Prashant; Singh, Navjeevan; Rasool, Farhan

149

Implant Reconstruction in Breast Cancer Patients Treated with Radiation Therapy  

Microsoft Academic Search

Background: Implant reconstruction in breast cancer patients treated with radiation therapy is controversial. Prior studies are limited by older prosthetic devices, reconstructive techniques, and radiation therapy protocols. Methods: A retrospective review was performed of patients who underwent tissue expansion and implant breast reconstruction performed by a single sur- geon after mastectomy for breast cancer from 1996 to 2003. Complications and

Jeffrey A. Ascherman; Matthew M. Hanasono; Martin I. Newman; Duncan B. Hughes

2006-01-01

150

Future Particle Accelerator Developments for Radiation Therapy  

NASA Astrophysics Data System (ADS)

During the last decade particle beam cancer therapy has seen a rapid increase in interest, and several new centers have been built, are currently under construction, or are in an advanced stage of planning. Typical treatment centers today consist of an accelerator capable of producing proton or ion beams in an energy range of interest for medical treatment, i.e. providing a penetration depth in water of about 30 cm, a beam delivery system to transport the produced beam to the patient treatment rooms, and several patient stations, allowing for an optimal usage of the continuously produced beam. This makes these centers rather large and consequently expensive. Only major hospital centers situated in an area where they can draw on a population of several million can afford such an installation. In order to spread the use of particle beam cancer therapy to a broader population base it will be necessary to scale down the facility size and cost. This can in principle be done by reducing the number of treatment rooms to one, eliminating the need of an elaborate beam delivery system, and thereby reducing the building size and cost. Such a change should be going in parallel with a reduction of the accelerator itself, and a number of approaches to this are currently being pursued. If successful, such developments could eventually lead to a compact system where all components would fit into a single shielded room, not much different in size from a typical radiation vault for radiotherapy with X-rays.

Holzscheiter, Michael H.; Bassler, Niels

151

Precise positioning of patients for radiation therapy  

SciTech Connect

A number of immobilization schemes which permit precise daily positioning of patients for radiation therapy are discussed. Pretreatment and post-treatment radiographs have been taken with the patient in the treatment position and analyzed to determine the amount of intratreatment movement. Studies of patients in the supine, seated and decubitus positions indicate mean movements of less than 1 mm with a standard deviation of less than 1 mm. Patients immobilized in the seated position with a bite block and a mask have a mean movement of about 0.5 mm +/- 0.3 mm (s.d.), and patients immobilized in the supine position with their necks hyperextended for submental therapy evidence a mean movement of about 1.4 mm +/- 0.9 mm (s.d.). With the exception of those used for the decubitus position, the immobilization devices are simply fabricated out of thermoplastic casting materials readily available from orthopedic supply houses. A study of day-to-day reproducibility of patient position using laser alignment and pretreatment radiographs for final verification of position indicates that the initial laser alignment can be used to position a patient within 2.2 mm +/- 1.4 mm (s.d.) of the intended position. These results indicate that rigid immobilization devices can improve the precision of radiotherapy, which would be advantageous with respect to both tumor and normal tissue coverage in certain situations.

Verhey, L.J.; Goitein, M.; McNulty, P.; Munzenrider, J.E.; Suit, H.D.

1982-02-01

152

Stereotactic body radiation therapy: a comprehensive review.  

PubMed

Stereotactic body radiation therapy (SBRT) is a novel technique that takes advantage of the technologic advancements in image guidance and radiation dose delivery to direct ablative doses to tumors with acceptable toxicity that was not previously achievable with conventional techniques. SBRT requires a high degree of confidence in tumor location provided by high quality diagnostic and near real-time imaging studies for accurate treatment delivery and precise assessment of physiologic tumor motion. In addition, stringent dosimetric parameters must be applied, paying close attention to the spatial arrangement of functional subunits in the adjacent normal tissues, to optimize clinical outcomes. Phase I/II trials for tumors of the lung, liver, spine, pancreas, kidney, and prostate provide evidence that the potent doses delivered with SBRT may provide results that rival surgery while avoiding the typical morbidities associated with that invasive approach. Further clinical study in the form of multi-institutional Phase II trials is currently underway, and ultimately collaborative efforts on a national level to support Phase III trials will be necessary, to firmly establish SBRT as a comparable noninvasive alternative to surgery. PMID:18091059

Chang, Brian K; Timmerman, Robert D

2007-12-01

153

Lacrimal gland lymphoma: Role of radiation therapy  

PubMed Central

Background: To report the clinical and treatment outcome of patients with lacrimal gland lymphoma (LGL) treated with radiation therapy (RT) at Fox Chase Cancer Center, Philadelphia, PA, USA. Materials and Methods: Institutional review board approved retrospective chart review of eight patients and literature review. Results: The study patients included six males and two females with a mean age of 70 years (range 58-88 years). The mean follow-up period was 23 months (range 374 months). Four patients had mucosa-associated lymphoid tissue (50%) lymphoma and four patients had other non-Hodgkin's lymphoma variants. Four patients had bilateral disease (50%). Four patients had primary LGL (stages I-IIAE, 50%) and four had LGL as part of systemic lymphoma (stage IVAE, 50%). The median RT dose was 2987 cGy (range 28803015 cGy). All patients had complete response to RT with symptomatic relief. Minimal dry eye was seen in all patients. There were no late effects such as corneal ulcer, radiation retinopathy, maculopathy, papillopathy, or secondary neovascular glaucoma. Conclusions: RT alone is an extremely effective treatment in the curative management of localized LGL and provides durable, local control of secondary LGL.

Townsend, Natasha; Turaka, Aruna; Smith, Mitchell R.

2012-01-01

154

Coronary artery disease following mediastinal radiation therapy  

SciTech Connect

Coronary artery disease occurred in four young men (mean age 41 years) who had received curative irradiation therapy for mediastinal malignancies 12 to 18 (mean 15) years previously. None was at high risk for developing coronary artery disease by Framingham criteria. Angiography demonstrated proximal coronary artery disease with normal distal vessels. Distribution of the lesions correlated with radiation dosimetry in that vessels exposed to higher radiation intensity were more frequently diseased. Three patients had coronary bypass grafting for intractable angina and are asymptomatic at 10 to 43 months. A total of 163 patients underwent mediastinal irradiation for lymphoma or thymoma between 1959 and 1980. Among the 29 who survived 10 or more years, five (18%) developed severe coronary artery disease, implicating thoracic radiotherapy as an important risk factor. Because of the importance of mantle irradiation in the treatment of lymphomas, the prevalence of these neoplasms, and the survival patterns following treatment, many long-term survivors may be at increased risk for the development of coronary artery disease. Recognition of the relationship between radiotherapy and coronary artery disease may lead to earlier diagnosis and more timely intervention. Standard surgical treatment may be particularly beneficial because of the relative youth of most of these patients and because the proximal distribution of typical lesions increases the likelihood of complete revascularization.

Annest, L.S.; Anderson, R.P.; Li, W.; Hafermann, M.D.

1983-02-01

155

Coronary artery disease following mediastinal radiation therapy  

SciTech Connect

Coronary artery disease occurred in four young men (mean age 41 years) who had received curative irradiation therapy for mediastinal malignancies 12 to 18 (mean 15) years previously. None was at high risk for developing coronary artery disease by Framingham criteria. Angiography demonstrated proximal coronary artery disease with normal distal vessels. Distribution of the lesions correlated with radiation dosimetry in that vessels exposed to higher radiation intensity were more frequently diseased. A total of 163 patients underwent mediastinal irradiation for lymphoma or thymoma between 1959 and 1980. Among the 29 who survived 10 or more years, five (18%) developed severe coronary artery disease, implicating thoracic radiotherapy as an important risk factor. Because of the importance of mantle irradiation in the treatment of lymphomas, the prevalence of these neoplasms, and the survival patterns following treatment, many long-term survivors may be at increased risk for the development of coronary artery disease. Recognition of the relationship between radiotherapy and coronary artery disease may lead to earlier diagnosis and more timely intervention.

Annest, L.S.; Anderson, R.P.; Li, W.; Hafermann, M.D.

1983-02-01

156

Radiation optic neuropathy after external beam radiation therapy for acromegaly: report of two cases  

Microsoft Academic Search

For diagnosing radiation optic neuropathy (RON) ophthalmological and imaging data were evaluated from 63 acromegalic patients, irradiated between 1967 and 1998. Two patients developed RON: one patient in one optic nerve 10 years and another patient in both optic nerves 5 months after radiation therapy. RON is a rare complication after external beam radiation therapy for acromegaly, which can occur

Alfons C. M van den Bergh; Marjanke A Hoving; Thera P Links; Robin P. F Dullaart; Adelita V Ranchor; Cees A ter Weeme; Alof A Canrinus; Ben G Szab; Jan-Willem R Pott

2003-01-01

157

Malignant thymoma: Role of radiation therapy in management  

SciTech Connect

Malignant thymoma is a rare tumor generally seen as an anterior mediastinal mass. Radiation therapy in ten patients with malignant thymoma diagnosed in 1968-1983 was reviewed retrospectively. Surgical therapy consisted of subtotal resection in four patients and biopsy only in six. Megavoltage irradiation in the dose range of 4600-5250 cGy was employed. In seven patients, a greater than 50% reduction in tumor mass followed radiation therapy. Local control was achieved in six patients. Three patients show no evidence of disease clinically, after a minimum follow-up study of 1 year. Radiation therapy is an important therapeutic modality in the control of malignant thymoma.

Kersh, C.R.; Eisert, D.R.; Hazra, T.A.

1985-07-01

158

Effects of Music Therapy on Elderly Extended Care Inpatients Receiving Radiation or Physical Therapy.  

National Technical Information Service (NTIS)

The study examined the effects of music therapy on a group of extended care patients including those receiving rehabilitation or radiation therapy. This project had several components including studies which: (1) examined the feasibility of a performance-...

M. A. Burke G. Kochersberger D. Weiner

1995-01-01

159

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

Code of Federal Regulations, 2012 CFR

...Nuclear Medicine Technologists, and Radiation Therapy Technologists F Appendix...Nuclear Medicine Technologists, and Radiation Therapy Technologists The following...Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

2012-10-01

160

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

Code of Federal Regulations, 2011 CFR

...Nuclear Medicine Technologists, and Radiation Therapy Technologists F Appendix...Nuclear Medicine Technologists, and Radiation Therapy Technologists The following...Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

2011-10-01

161

Diagnosis of delayed cerebral radiation necrosis following proton beam therapy  

SciTech Connect

A 27-year-old man developed delayed cerebral radiation necrosis following proton beam therapy to an arteriovenous malformation. Neuroimaging with technetium 99m diethylenetriamine penta-acetic acid and positron emission tomographic scanning with fludeoxyglucose F 18 aided in his evaluation. Significant improvement of his neurologic deficits resulted from corticosteroid therapy. Clinical resolution was corroborated by serial computed tomographic scans demonstrating regression of the abnormality (a mass lesion). Various facets of radiation injury are discussed, including pathogenesis, risk factors, diagnosis, and therapy.

Kaufman, M.; Swartz, B.E.; Mandelkern, M.; Ropchan, J.; Gee, M.; Blahd, W.H. (Wadsworth Veterans Administration Medical Center, Los Angeles, CA (USA))

1990-04-01

162

Technological Advances in Radiation Therapy for Prostate Cancer  

Microsoft Academic Search

Radiation therapy (RT) for prostate cancer has made huge strides over the past two decades. The addition of image guidance\\u000a has allowed radiation oncologists to ensure accurate delivery of increasingly precise radiation treatment plans using newer\\u000a conformal therapy methods such as three-dimensional conformal RT, intensity-modulated RT, and proton beam RT. Regardless of\\u000a the specific treatment technique, patients can depend on

Mehee Choi; Arthur Y. Hung

2010-01-01

163

Cancer and Radiation Therapy: Current Advances and Future Directions  

PubMed Central

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.

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

2012-01-01

164

21 CFR 892.5770 - Powered radiation therapy patient support assembly.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Powered radiation therapy patient support assembly...Devices § 892.5770 Powered radiation therapy patient support assembly. (a) Identification. A powered radiation therapy patient support...

2013-04-01

165

21 CFR 892.5710 - Radiation therapy beam-shaping block.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Radiation therapy beam-shaping block. 892...Therapeutic Devices § 892.5710 Radiation therapy beam-shaping block. (a) Identification. A radiation therapy beam-shaping block...

2013-04-01

166

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

Code of Federal Regulations, 2013 CFR

...false Medical charged-particle radiation therapy system. 892.5050 ...5050 Medical charged-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system is a device...

2013-04-01

167

Auger radiation targeted into DNA: a therapy perspective  

Microsoft Academic Search

BackgroundAuger electron emitters that can be targeted into DNA of tumour cells represent an attractive systemic radiation therapy goal. In the situation of DNA-associated decay, the high linear energy transfer (LET) of Auger electrons gives a high relative biological efficacy similar to that of ? particles. In contrast to ? radiation, however, Auger radiation is of low toxicity when decaying

Franz Buchegger; Florence Perillo-Adamer; Yves M. Dupertuis; Angelika Bischof Delaloye

2006-01-01

168

Image-Guidance for Stereotactic Body Radiation Therapy  

Microsoft Academic Search

The term stereotactic body radiation therapy (SBRT) describes a recently introduced external beam radiation paradigm by which small lesions outside the brain are treated under stereotactic conditions, in a single or few fractions of high-dose radiation delivery. Similar to the treatment planning and delivery process for cranial radiosurgery, the emphasis is on sparing of adjacent normal tissues through the creation

Martin. Fuss; Judit Boda-Heggemann; Nikos Papanikolau; Bill J. Salter

2007-01-01

169

JCOG Radiation Therapy Study Group: history and achievements.  

PubMed

The Radiation Therapy Study Group (RTSG) of the Japan Clinical Oncology Group (JCOG) was established in 2003. The missions of this group are to develop new standards of care with innovative, advanced technology radiation therapy, both for single- and multi-modality cancer treatment, and to improve radiation therapy quality and outcomes of JCOG trials conducted by other organ-oriented groups. In 2004, the first RTSG trial, a Phase II study of stereotactic body radiation therapy for Stage IA non-small cell lung cancer (JCOG 0403), was initiated. Four other trials are currently open for accrual. JCOG 0702 is a Phase I study of stereotactic body radiation therapy in patients with T2N0M0 non-small cell lung cancer. JCOG 0701 is a Phase III study comparing accelerated fractionation with conventional fractionation radiation therapy for T1-2N0M0 glottic cancer. JCOG 0906 is a multicenter safety trial of hypofractionated radiation therapy after breast-conserving surgery in patients with margin-negative invasive breast cancer. JCOG 1015 is a Phase II study of intensity-modulated radiation therapy with chemotherapy for loco-regionally advanced nasopharyngeal cancer. Other RTSG activities include a medical physics working group responsible for dosimetry audits; a genetic analysis working group involved in accompanying research to analyze single-nucleotide polymorphisms to identify predictors of radiation toxicities; a working group that has developed atlases of clinical target volumes for uterine cervical cancer; and participation in the Harmonisation Group to promote global harmonization of radiotherapy and radiotherapy quality assurance among trial groups. Further efforts to improve radiation therapy quality and outcomes of cancer treatment are necessary. PMID:21980050

Ishikura, Satoshi; Ito, Yoshinori; Hiraoka, Masahiro

2011-10-06

170

Fishbowl Plaques.  

ERIC Educational Resources Information Center

|Presents an elementary art activity that successfully teaches the process of slabbing by having students create fishbowl plaques. Explains the process step-by-step beginning with a demonstration to the students along with showing previous examples. Endorses a type of clay that fires white because the glaze colors are much more vibrant. (CMK)|

Lambert, Phyllis Gilchrist

1998-01-01

171

Radiation Therapy for Chloroma (Granulocytic Sarcoma)  

SciTech Connect

Objectives: Chloroma (granulocytic sarcoma) is a rare, extramedullary tumor of immature myeloid cells related to acute nonlymphocytic leukemia or myelodysplastic syndrome. Radiation therapy (RT) is often used in the treatment of chloromas; however, modern studies of RT are lacking. We reviewed our experience to analyze treatment response, disease control, and toxicity associated with RT to develop treatment algorithm recommendations for patients with chloroma. Patients and Methods: Thirty-eight patients who underwent treatment for chloromas at our institution between February 1990 and June 2010 were identified and their medical records were reviewed and analyzed. Results: The majority of patients that presented with chloroma at the time of initial leukemia diagnosis (78%) have not received RT because it regressed after initial chemotherapy. Yet most patients that relapsed or remained with chloroma after chemotherapy are in the RT cohort (90%). Thirty-three courses of RT were administered to 22 patients. Radiation subsite breakdown was: 39% head and neck, 24% extremity, 9% spine, 9% brain, 6% genitourinary, 6% breast, 3% pelvis, and 3% genitourinary. Median dose was 20 (6-36) Gy. Kaplan-Meier estimates of progression-free survival and overall survival in the RT cohort were 39% and 43%, respectively, at 5 years. At a median follow-up of 11 months since RT, only 1 patient developed progressive disease at the irradiated site and 4 patients developed chloromas at other sites. RT was well tolerated without significant acute or late effects and provided symptom relief in 95% of cases. Conclusions: The majority of patients with chloromas were referred for RT when there was extramedullary progression, marrow relapse, or rapid symptom relief required. RT resulted in excellent local disease control and palliation of symptoms without significant toxicity. We recommend irradiating chloromas to at least 20 Gy, and propose 24 Gy in 12 fractions as an appropriate regimen.

Bakst, Richard; Wolden, Suzanne [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Yahalom, Joachim, E-mail: yahalomj@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2012-04-01

172

Managing Radiation Therapy Side Effects: What to Do about Hair Loss (Alopecia)  

MedlinePLUS

... out 2 to 3 weeks after your first radiation therapy session. If you are getting radiation to the ... gov/livehelp NCI has a series of 9 Radiation Therapy Side Effects Sheets at: www.cancer.gov/radiation- ...

173

Geometric accuracy in radiation therapy: Dosimetric, imaging and economic considerations  

NASA Astrophysics Data System (ADS)

In 2007 in Canada, 159,900 men and women will be diagnosed with cancer. Radiation Therapy (RT) is the treatment of cancer by irradiating malignant tissue with ionizing radiation and it is used on up to 50% of all cancers. The objective of radiation therapy is to deliver a lethal dose of radiation to the tumour while sparing the surrounding healthy tissues and organs at risks (OARs). Thus, the accuracy with which the radiation therapy process must be carried out is critical. The presence of setup errors and uncertainties throughout the RT process impacts the dose received by the tumour and OARs and can compromise the outcome for the patient. This thesis focuses on the study of the limiting geometrical accuracy imposed by factors present in radiation therapy process (such as setup errors and uncertainties or the spatial resolution of the imaging systems that we use) and its consequences for the patient. The consequences are quantified through the use of a physical outcome surrogate, the Equivalent Uniform Dose (EUD), which numerically describes the dose distribution received by the target and normal structures surrounding it. A cost-outcome analysis is presented in which the incremental cost of radiation therapy is directly related to the patients outcome (using the EUD) for using various imaging modalities and correction protocols in Image Guided Adaptive Radiation Therapy (IGART).

Ploquin, Nicolas P.

174

Overcoming the hypoxic barrier to radiation therapy with anaerobic bacteria  

PubMed Central

The low level of oxygenation within tumors is a major cause of radiation treatment failures. We theorized that anaerobic bacteria that can selectively destroy the hypoxic regions of tumors would enhance the effects of radiation. To test this hypothesis, we used spores of Clostridium novyi-NT to treat transplanted tumors in mice. The bacteria were found to markedly improve the efficacy of radiotherapy in several of the mouse models tested. Enhancement was noted with external beam radiation derived from a Cs-137 source, systemic radioimmunotherapy with an I-131-conjugated monoclonal antibody, and a previously undescribed form of experimental brachytherapy using plaques loaded with I-125 seeds. C. novyi-NT spores added little toxicity to the radiotherapeutic regimens, and the combination resulted in long-term remissions in a significant fraction of animals.

Bettegowda, Chetan; Dang, Long H.; Abrams, Ross; Huso, David L.; Dillehay, Larry; Cheong, Ian; Agrawal, Nishant; Borzillary, Scott; McCaffery, J. Michael; Watson, E. Latice; Lin, Kuo-Shyan; Bunz, Fred; Baidoo, Kwamena; Pomper, Martin G.; Kinzler, Kenneth W.; Vogelstein, Bert; Zhou, Shibin

2003-01-01

175

On probabilistically defined margins in radiation therapy  

NASA Astrophysics Data System (ADS)

Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem-based recommendations for margin construction that were derived for uncorrelated distributions of errors (van Herk, Remeijer, Rasch and Lebesque 2000 Int. J. Radiat. Oncol. Biol. Phys. 47 1121-35 Stroom, De Boer, Huizenga and Visser 1999 Int. J. Radiat. Oncol. Biol. Phys. 43 905-19).

Papiez, Lech; Langer, Mark

2006-08-01

176

Surgical therapy of Peyronie's disease by partial plaque excision and grafting with collagen fleece: feasibility study of a new technique.  

PubMed

Surgery is gold-standard for correction of Peyronie's curvature. Grafting is preferred in advanced deviations. We present our novel surgical technique and early results of grafting with collagen fleece. Patients with stable Peyronie's disease (PD) were included. Grafting was performed by a ready-to-use collagen fleece coated with tissue sealant (TachoSil, Nycomed, Konstanz, Germany), following partial plaque excision/incision. Results of correction were documented by artificial erection. In all, n=70 consecutive patients underwent surgery. Mean patient age was 56.4 years (range: 33-72); 88.6% of patients had dorsal deviation, 11.4% lateral or ventral deviation. Grafting after partial plaque excision was performed in 61 patients (87.1%), after plaque incision in 2 (2.9%) patients. In the former patients, mean operative time was 94.2?min (range: 65-165). Totally straightness was achieved in 83.6%. Three patients required surgical drainage because of subcutaneous haematoma formation. After mean early follow-up of 5.2 days (range: 2-15), glans sensation was normal in 56 patients (91.8%). Seven patients (10.0%) underwent Nesbit procedure alone. Grafting by collagen fleece in PD is feasible and promising. Major advantages are decreased operative times and easy application. Moreover, an additional haemostatic effect is provided. However, long-term clinical outcomes are necessary to confirm these encouraging findings. PMID:23446807

Hatzichristodoulou, G; Gschwend, J E; Lahme, S

2013-02-28

177

Image registration in adaptive radiation therapy  

NASA Astrophysics Data System (ADS)

This thesis focuses on the development, validation and application of image registration software in adaptive radiation therapy. The contents can be divided into three components: deformable image registration validation, rigid registration based daily patient positioning and deformable image registration for dose accumulation. In the first component, a protocol was developed for the validation of commercial deformable registration systems, applicable to a wide range of applications. The protocol was used to assess the capabilities of a commercial system and results suggest that deformable registration could potentially be optimized by treating applications separately instead of using one algorithm for all applications. The use of rigid registration for daily positioning of helical tomotherapy prostate patients was investigated in the second component. We quantified alignment discrepancies between daily treatment MVCT images and their corresponding planning CT images resulting from different automated rigid registration schemes. Based on alignments, errors in prostate positioning that would occur if patient repositioning was based on mutual information optimization of entire images or simply bony anatomy were evaluated, with the latter having a 20% decreased average prostate misplacement. The dosimetric implications of performing patient positioning based on either bony anatomy matching or prostate matching in treatment and planning images were also investigated. Prostate doses were fairly insensitive, however, doses to the radiation sensitive bladder and rectum varied with not only positioning strategy, but also the direction of daily prostate motion. The third component of this thesis involves the use of deformable registration and dose accumulation in the comparison of treatment and planning doses. Using correlation coefficient optimization and assuming B-spline parameterized deformations, we demonstrated that deformable registration can be improved by performing separate registrations over each clinically relevant region on interest. Our deformable model was incorporated into a dose accumulation framework and cumulative treatment doses were compared to those that were planned. In addition, cumulative doses that would have been delivered had patient positioning been based on bone matching and prostate matching were also evaluated. These studies may suggest that daily anatomical variations play a greater role in treatment dosimetry than does the selection of registration based image guidance procedure.

Rivest, Ryan Chad

178

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

PubMed

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. PMID:21275334

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

2010-01-01

179

Brain tumors and synchrotron radiation: Methodological developments in quantitative brain perfusion imaging and radiation therapy  

Microsoft Academic Search

High-grade gliomas are the most frequent type of primary brain tumors in adults. Unfortunately, the management of glioblastomas is still mainly palliative and remains a difficult challenge, despite advances in brain tumor molecular biology and in some emerging therapies. Synchrotron radiation opens fields for medical imaging and radiation therapy by using monochromatic intense x-ray beams. It is now well known

Jean-Franois Adam

2005-01-01

180

REVIEW: Motion effects in (intensity modulated) radiation therapy: a review  

NASA Astrophysics Data System (ADS)

During a course of fractionated radiation therapy and between the fractions the tissues of the human body may move relative to some reference location in which the radiation therapy was planned. This has been known for over a century and simple 'coping mechanisms' (margins) have been used to approximately compensate. Since the introduction of highly accurate conformal radiation therapy and intensity-modulated radiation therapy (IMRT) attention has focused strongly in the last few years on understanding and compensating more appropriately for these motions. Thus, unlike most of the reviews in this special 50th anniversary issue which look back over decades of development, this one looks back at most within just the past decade and reviews the current situation. There is still much more work to be done and many of the techniques reviewed are themselves not yet implemented widely in the clinic.

Webb, S.

2006-07-01

181

Applicator-guided intensity-modulated radiation therapy  

Microsoft Academic Search

Purpose: We are introducing a novel method for delivering highly conformal dose distributions to cervical cancer tumors using external beam intensity-modulated radiation therapy. The method, termed applicator-guided intensity-modulated radiation therapy (AGIMRT), will use an applicator substitute placed in the vagina and uterus to provide spatial registration and immobilization of the gynecologic organs. The main reason for the applicator substitute will

Daniel A Low; Perry W Grigsby; James F Dempsey; Sasa Mutic; Jeffrey F Williamson; Jerry Markman; K. S. Clifford Chao; Eric E Klein; James A Purdy

2002-01-01

182

Thyroid neoplasia following radiation therapy for Hodgkin's lymphoma  

SciTech Connect

The question of thyroid neoplasia following high-dose radiation treatment to the neck and mediastinum for malignant neoplasms such as Hodgkin's lymphoma in children and young adults has been raised recently. Five patients, 19 to 39 years old, were operated on for thyroid neoplasms that developed following cervical and mediastinal radiation therapy for Hodgkin's lymphoma. Three patients had papillary carcinomas and two had follicular adenomas. The latency period between radiation exposure and the diagnosis of thyroid neoplasm ranged from eight to 16 years. This limited series provided strong support for the recommendation that children and young adults who are to receive high-dose radiation therapy to the head, neck, and mediastinum should receive suppressive doses of thyroxine prior to radiation therapy in order to suppress thyrotropin (thyroid-stimulating hormone) and then be maintained on a regimen of suppression permanently.

McHenry, C.; Jarosz, H.; Calandra, D.; McCall, A.; Lawrence, A.M.; Paloyan, E.

1987-06-01

183

Radiation therapy among atomic bomb survivors, Hiroshima and Nagasaki.  

PubMed

As a follow-up to the two previous surveys of radiation therapy among the atomic bomb survivors, a large-scale survey was performed to document (1) the number of radiation therapy treatments received by the atomic bomb survivors and (2) the types of radiation treatments conducted in Hiroshima and Nagasaki. The previous two surveys covered the radiation treatments among the Radiation Effects Research Foundation Adult Health Study (AHS) population, which is composed of 20,000 persons. In the present survey, the population was expanded to include the Life Span Study (LSS), including 93,611 atomic bomb survivors and 26,517 Hiroshima and Nagasaki citizens who were not in the cities at the times of the bombings. The LSS population includes the AHS population. The survey was conducted from 1981 to 1984. The survey teams reviewed all the medical records for radiation treatments of 24,266 patients at 11 large hospitals in Hiroshima and Nagasaki. Among them, the medical records for radiation treatments of 1556 LSS members were reviewed in detail. By analyzing the data obtained in the present and previous surveys, the number of patients receiving radiation therapy was estimated to be 4501 (3.7%) in the LSS population and 1026 (5.1%) in the AHS population between 1945-1980. During 1945-1965, 98% of radiation treatments used medium-voltage X rays, and 66% of the treatments were for benign diseases. During 1966-1980, 94% of the radiation treatments were for malignant neoplasms. During this period, 60Co gamma-ray exposure apparatus and high-energy electron accelerators were the prevalent mode of treatment in Hiroshima and in Nagasaki, respectively. The mean frequency of radiation therapy among the LSS population was estimated to have been 158 courses/year during 1945-1965 and 110 courses/year during 1966-1980. The present survey revealed that 377 AHS members received radiation therapy. The number was approximately twice the total number of cases found in the previous two surveys. Thus the data on radiation therapy in the AHS members have been updated well by this survey, and will provide information for more precise dose-response analyses of radiation effects in the AHS population. The information extracted from the medical records of the hospitals consisted of hospital names, treatment periods, body sites treated, diagnoses, treatment doses, radiation sources, the field sizes of the exposures and the data for identification of the patients. These data will be essential in estimating the organ doses from scattered radiation and in evaluating the effects of therapeutic radiation. PMID:9611100

Kato, K; Antoku, S; Russell, W J; Fujita, S; Pinkston, J A; Hayabuchi, N; Hoshi, M; Kodama, K

1998-06-01

184

Persistence of endometrial activity after radiation therapy for cervical carcinoma  

SciTech Connect

Radiation therapy is a proved treatment for cervical carcinoma; however, it destroys ovarian function and has been thought to ablate the endometrium. Estrogen replacement therapy is often prescribed for patients with cervical carcinoma after radiation therapy. A review of records of six teaching hospitals revealed 16 patients who had endometrial sampling for uterine bleeding after standard radiation therapy for cervical carcinoma. Fifteen patients underwent dilatation and curettage, and one patient underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy when a dilatation and curettage was unsuccessful. Six patients had fibrosis and inflammation of the endometrial cavity, seven had proliferative endometrium, one had cystic hyperplasia, one had atypical adenomatous hyperplasia, and one had adenocarcinoma. Although the number of patients who have an active endometrium after radiation therapy for cervical carcinoma is not known, this report demonstrates that proliferative endometrium may persist, and these patients may develop endometrial hyperplasia or adenocarcinoma. Studies have indicated that patients with normal endometrial glands have an increased risk of developing endometrial adenocarcinoma if they are treated with unopposed estrogen. Patients who have had radiation therapy for cervical carcinoma should be treated with estrogen and a progestational agent to avoid endometrial stimulation from unopposed estrogen therapy.

Barnhill, D.; Heller, P.; Dames, J.; Hoskins, W.; Gallup, D.; Park, R.

1985-12-01

185

Can radiation therapy treatment planning system accurately predict surface doses in postmastectomy radiation therapy patients?  

SciTech Connect

Skin doses have been an important factor in the dose prescription for breast radiotherapy. Recent advances in radiotherapy treatment techniques, such as intensity-modulated radiation therapy (IMRT) and new treatment schemes such as hypofractionated breast therapy have made the precise determination of the surface dose necessary. Detailed information of the dose at various depths of the skin is also critical in designing new treatment strategies. The purpose of this work was to assess the accuracy of surface dose calculation by a clinically used treatment planning system and those measured by thermoluminescence dosimeters (TLDs) in a customized chest wall phantom. This study involved the construction of a chest wall phantom for skin dose assessment. Seven TLDs were distributed throughout each right chest wall phantom to give adequate representation of measured radiation doses. Point doses from the CMS Xio Registered-Sign treatment planning system (TPS) were calculated for each relevant TLD positions and results correlated. There were no significant difference between measured absorbed dose by TLD and calculated doses by the TPS (p > 0.05 (1-tailed). Dose accuracy of up to 2.21% was found. The deviations from the calculated absorbed doses were overall larger (3.4%) when wedges and bolus were used. 3D radiotherapy TPS is a useful and accurate tool to assess the accuracy of surface dose. Our studies have shown that radiation treatment accuracy expressed as a comparison between calculated doses (by TPS) and measured doses (by TLD dosimetry) can be accurately predicted for tangential treatment of the chest wall after mastectomy.

Wong, Sharon [National University of Singapore, Yong Loo Lin School of Medicine (Singapore); Back, Michael [Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, New South Wales (Australia); Tan, Poh Wee; Lee, Khai Mun; Baggarley, Shaun [National University, Cancer Institute, Department of Radiation Oncology, National University, Hospital, Tower Block (Singapore); Lu, Jaide Jay, E-mail: mdcljj@nus.edu.sg [National University of Singapore, Yong Loo Lin School of Medicine (Singapore); National University, Cancer Institute, Department of Radiation Oncology, National University, Hospital, Tower Block (Singapore)

2012-07-01

186

Results of conservative surgery and radiation therapy for breast cancer  

Microsoft Academic Search

For stage I or II breast cancer, conservative surgery and radiation therapy are as effective as modified radical or radical mastectomy. In most cases, cosmetic considerations and the availability of therapy are the primary concerns. The extent of a surgical resection less than a mastectomy has not been a subject of a randomized trial and is controversial. It appears that

R. T. Osteen; B. L. Smith

1990-01-01

187

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

Microsoft Academic Search

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

Jrn H. Risse; Carsten Ponath; Holger Palmedo; Christian Menzel; Frank Grnwald; Hans-J. Biersack

2001-01-01

188

Stereotactic body radiation therapy: a novel treatment modality  

Microsoft Academic Search

Stereotactic body radiation therapy (SBRT) involves the delivery of a small number of ultra-high doses of radiation to a target volume using very advanced technology and has emerged as a novel treatment modality for cancer. The role of SBRT is most important at two cancer stagesin early primary cancer and in oligometastatic disease. This modality has been used in the

Achilles J. Fakiris; Eric L. Chang; Nina A. Mayr; Jian Z. Wang; Lech Papiez; Bin S. Teh; Ronald C. McGarry; Higinia R. Cardenes; Robert D. Timmerman; Simon S. Lo

2009-01-01

189

Cranial Radiation Therapy and Damage to Hippocampal Neurogenesis  

ERIC Educational Resources Information Center

|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

Monje, Michelle

2008-01-01

190

What to Know about External Beam Radiation Therapy  

MedlinePLUS

... an x-ray to take pictures inside your body. In cancer treatment, higher doses of radiation are used to destroy cancer cells. National Cancer Institute U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health Understanding Radiation Therapy ...

191

Guidelines for respiratory motion management in radiation therapy  

PubMed Central

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.

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

192

Stage III thymoma: results of postoperative radiation therapy  

SciTech Connect

The results of postoperative radiation therapy in 12 patients with stage III thymoma treated during 1966-1986 were reviewed. Surgical therapy consisted of total resection in one, subtotal resection in seven, and biopsy only in four. Megavoltage irradiation in the dose range of 3,000-5,600 cGy was employed, with nine patients receiving a dose of at least 5,000 cGy. The local control rate was 67%. The actuarial observed and adjusted 5-year survival rates were 57% and 75%, respectively. These results indicate that postoperative radiation therapy is an effective therapeutic modality in the control of stage III thymoma.

Krueger, J.B.; Sagerman, R.H.; King, G.A.

1988-09-01

193

Prototype demonstration of radiation therapy planning code system  

SciTech Connect

This is the final report of a one-year, Laboratory-Directed Research and Development project at the Los Alamos National Laboratory (LANL). Radiation therapy planning is the process by which a radiation oncologist plans a treatment protocol for a patient preparing to undergo radiation therapy. The objective is to develop a protocol that delivers sufficient radiation dose to the entire tumor volume, while minimizing dose to healthy tissue. Radiation therapy planning, as currently practiced in the field, suffers from inaccuracies made in modeling patient anatomy and radiation transport. This project investigated the ability to automatically model patient-specific, three-dimensional (3-D) geometries in advanced Los Alamos radiation transport codes (such as MCNP), and to efficiently generate accurate radiation dose profiles in these geometries via sophisticated physics modeling. Modem scientific visualization techniques were utilized. The long-term goal is that such a system could be used by a non-expert in a distributed computing environment to help plan the treatment protocol for any candidate radiation source. The improved accuracy offered by such a system promises increased efficacy and reduced costs for this important aspect of health care.

Little, R.C.; Adams, K.J.; Estes, G.P.; Hughes, L.S. III; Waters, L.S. [and others

1996-09-01

194

Planning and delivery of intensity-modulated radiation therapy  

SciTech Connect

Intensity modulated radiation therapy (IMRT) is an advanced form of external beam radiation therapy. IMRT offers an additional dimension of freedom as compared with field shaping in three-dimensional conformal radiation therapy because the radiation intensities within a radiation field can be varied according to the preferences of locations within a given beam direction from which the radiation is directed to the tumor. This added freedom allows the treatment planning system to better shape the radiation doses to conform to the target volume while sparing surrounding normal structures. The resulting dosimetric advantage has shown to translate into clinical advantages of improving local and regional tumor control. It also offers a valuable mechanism for dose escalation to tumors while simultaneously reducing radiation toxicities to the surrounding normal tissue and sensitive structures. In less than a decade, IMRT has become common practice in radiation oncology. Looking forward, the authors wonder if IMRT has matured to such a point that the room for further improvement has diminished and so it is pertinent to ask what the future will hold for IMRT. This article attempts to look from the perspective of the current state of the technology to predict the immediate trends and the future directions. This article will (1) review the clinical experience of IMRT; (2) review what we learned in IMRT planning; (3) review different treatment delivery techniques; and finally, (4) predict the areas of advancements in the years to come.

Yu, Cedric X.; Amies, Christopher J.; Svatos, Michelle [Department of Radiation Oncology, University of Maryland School of Medicine, 22 South Greene Street, Baltimore, Maryland 21201 (United States); Siemens Medical Solutions USA, Inc., Oncology Care Systems Group, 4040 Nelson Avenue, Concord, California 94520 (United States); Translational Research, Varian Medical Systems, 3100 Hansen Way M/S E263 Palo Alto, California 94304-1038 (United States)

2008-12-15

195

Rationale for combining surgery and radiation therapy  

SciTech Connect

The combination of radiation and surgery is being employed increasingly in preference to radical surgery alone or high radiation dose alone in the treatment of malignant epithelial and mesenchymal neoplasms. The basis for this interest is that the scope of the surgery and/or the radiation dose level are less than if either were employed alone. A reduction in treatment related morbidity, improved cosmetic and functional status, and in some instances a lower local failure rate may be achieved by this approach. The rationale for combining radiation and surgery is that radiation at moderate dose levels is effective in the eradication of microscopic extensions of tumor beyond the clearly obvious mass while the surgery (usually more conservative) removes the principal mass.

Suit, H.D.; Todoroki, T.

1985-05-01

196

Radiation-induced peripheral nerve neurofibromata in a patient receiving hypofractionated radiation therapy.  

PubMed

Radiation-induced peripheral nerve tumor, in particular a benign entity such as a neurofibroma, is rare, with only a few cases being reported so far. We demonstrate a case of radiation-induced neurofibromata along the left cervical nerve roots in a man with a background of localized targeted hypofractionated radiation therapy as adjuvant treatment for left cervical nodal metastasis complicating nasopharyngeal carcinoma. The toxicity of high-dose radiation in a hypofractionated regime is also stressed. PMID:18653682

Lai, V; Wong, Y C; Poon, W L; Fu, Y P; Lam, T C; Yuen, S C

2008-07-24

197

Vascular strategies for enhancing tumour response to radiation therapy.  

PubMed

Radiation therapy is prescribed to more than 50% of patients diagnosed with cancer. Although mechanisms of interaction between radiation and tumour cells are well understood on a molecular level, much remains uncertain concerning the interaction of radiation with the tumour as a whole. Recent studies have demonstrated that single large doses of radiation (8-20 Gy) may primarily target tumour endothelial cells, leading to secondary tumour clonogenic cell death. These studies suggest that blood vessels play an important role in radiation response. As a result, various strategies have been proposed to effectively combine radiation with vascular targeting agents. While most proposed schemes focus on methods to disrupt tumour blood vessels, recent evidence supporting that some anti-angiogenic agents may "normalize" tumour blood vessels, in turn enhancing tumour oxygenation and radiosensitivity, indicates that there may be more efficient strategies. Furthermore, vascular targeting agents have recently been demonstrated to enhance radiation therapy by targeting endothelial cells. When combined with radiation, these agents are believed to cause even more localized vascular destruction followed by tumour clonogenic cell death. Taken together, it is now crucial to elucidate the role of tumour blood vessels in radiation therapy response, in order to make use of this knowledge in developing therapeutic strategies that target tumour vasculature above and beyond classic clonogenic tumour cell death. In this report, we review some major developments in understanding the importance of tumour blood vessels during radiation therapy. A discussion of current imaging modalities used for studying vascular response to treatments will also be presented. PMID:22568629

El Kaffas, Ahmed; Tran, William; Czarnota, Gregory J

2012-05-07

198

Craniopharyngiomas: fluctuation in cyst size following surgery and radiation therapy.  

PubMed

Patients with craniopharyngiomas who demonstrate cyst enlargement after surgery and radiation are often presumed to be treatment failures. Therapeutic approaches in various centers include repetitive cyst aspirations, surgical reexcision, and installation of cytotoxic agents such as methotrexate, 32P, or 198Au. Each intervention has associated severe or even lethal side effects. Not all patients with craniopharyngioma who have cystic enlargement after primary therapy require an intervention, as demonstrated by 4 patients recently managed in the University of Rochester Medical Center. Since 1978, when computed tomography was routinely in use, we have managed 11 patients with craniopharyngiomas who were treated with surgery followed by radiation therapy. Three of these patients demonstrated post-irradiation enlargement of the residual cystic component followed by a decrease in size without surgical intervention. An additional patient showed cystic growth followed by stabilization of size. It is noteworthy that the cyst enlarged within the first 5 months after radiation therapy in the 3 patients who subsequently demonstrated a diminution in the size of their cysts. This suggests that the mechanism for cyst formation remained intact and subsequently abated because of a radiation-induced lesion. We conclude that after treatment with surgery and radiation therapy, the cystic component of craniopharyngiomas may increase and, without intervention, subsequently decrease in size. Thus, in the asymptomatic patient who demonstrates cystic growth soon after primary therapy, close observation alone may be warranted. PMID:2927598

Constine, L S; Randall, S H; Rubin, P; McDonald, J

1989-01-01

199

Postmastectomy Radiation Therapy: An Overview for the Practicing Surgeon  

PubMed Central

Locoregional control of breast cancer is the shared domain and responsibility of surgeons and radiation oncologists. Because surgeons are often the first providers to discuss locoregional control and recurrence risks with patients and because they serve in a key gatekeeping role as referring providers for radiation therapy, a sophisticated understanding of the evidence regarding radiotherapy in breast cancer management is essential for the practicing surgeon. This paper synthesizes the complex and evolving evidence regarding the role of radiation therapy after mastectomy. Although substantial evidence indicates that radiation therapy can reduce the risk of locoregional failure after mastectomy (with a relative reduction of risk of approximately two-thirds), debate persists regarding the specific subgroups who have sufficient risks of residual microscopic locoregional disease after mastectomy to warrant treatment with radiation. This paper reviews the evidence available to guide appropriate referral and patient decision making, with special attention to areas of controversy, including patients with limited nodal disease, those with large tumors but negative nodes, node-negative patients with high risk features, patients who have received systemic chemotherapy in the neoadjuvant setting, and patients who may wish to integrate radiation therapy with breast reconstruction surgery.

Jagsi, Reshma

2013-01-01

200

Combination therapy with triamcinolone acetonide and bevacizumab for the treatment of severe radiation maculopathy in patients with posterior uveal melanoma  

PubMed Central

Purpose To evaluate the role of intravitreal triamcinolone acetonide in patients who developed severe, visually compromising radiation maculopathy or progressed despite anti-angiogenic treatments. Methods An Institutional Review Board approved, consecutive, retrospective study from 2006 to 2009 of patients who developed severe, visually compromising radiation retinopathy manifesting as macular edema secondary to iodine-125 plaque brachytherapy for posterior uveal melanoma, were treated with a combination of intravitreal bevacizumab and intravitreal triamcinolone. Patients were evaluated with spectral domain optical coherence tomography (SD-OCT) at 24 month intervals following plaque removal. Treatment with intravitreal bevacizumab commenced at the first signs of visually compromising macular edema diagnosed with SD-OCT. Triamcinolone acetonide was administered to patients with severe maculopathy as consolidative therapy, or for patients that were refractory to repeated bevacizumab injections with persistent or worsening cystoid macular edema and lack of improvement or progressive worsening of best corrected visual acuity (BCVA). Results Twenty-five patients were evaluated after receiving a combination of intravitreal bevacizumab and triamcinolone. Initial treatment commenced at a mean of 14.5 (range of 242) months after plaque brachytherapy. Patients were given a mean of two injections (range 16) of triamcinolone acetonide, and a mean of 8.8 bevacizumab injections (range of 126) with a mean follow-up of 31.2 months. Radiation maculopathy upon first detection had a mean SD-OCT grade of 3.6 (median = 4), with an associated mean entry level BCVA of 20/70. Visual acuity at time of first intravitreal triamcinolone was 20/138. At last follow-up (mean of 45.5 months after plaque brachytherapy) mean BCVA was 20/136; however, 9 of 25 (36%) patients who presented with severe radiation maculopathy demonstrated 20/50 or better vision at last follow-up. Conclusion This case series suggests a beneficial role for intravitreal triamcinolone as a consolidation treatment for patients who present with severe radiation maculopathy or as an adjuvant to bevacizumab for refractory or progressive maculopathy.

Shah, Nisha V; Houston, Samuel K; Markoe, Arnold; Murray, Timothy G

2013-01-01

201

Applications of laser-accelerated particle beams for radiation therapy  

NASA Astrophysics Data System (ADS)

Proton beams are more advantageous than high-energy photons and electrons for radiation therapy because of their finite penetrating range and the Bragg peak near the end of their range, which have been utilized to achieve better dose conformity to the treatment target allowing for dose escalation and/or hypofractionation to increase local tumor control, reduce normal tissue complications and/or treatment time/cost. Proton therapy employing conventional particle acceleration techniques is expensive because of the large accelerators and treatment gantries that require excessive space and shielding. Compact proton acceleration systems are being sought to improve the cost-effectiveness for proton therapy. This paper reviews the physics principles of laser-proton acceleration and the development of prototype laserproton therapy systems as a solution for widespread applications of advanced proton therapy. The system design, the major components and the special delivery techniques for energy and intensity modulation are discussed in detail for laser-accelerated proton therapy.

Ma, C.-M.; Fourkal, E.; Li, J. S.; Veltchev, I.; Luo, W.; Fan, J. J.; Lin, T.; Tafo, A.

2011-05-01

202

Study design and rationale of "Synergistic Effect of Combination Therapy with Cilostazol and ProbUcol on Plaque Stabilization and Lesion REgression (SECURE)" study: a double-blind randomised controlled multicenter clinical trial  

PubMed Central

Background Probucol, a cholesterol-lowering agent that paradoxically also lowers high-density lipoprotein cholesterol has been shown to prevent progression of atherosclerosis. The antiplatelet agent cilostazol, which has diverse antiatherogenic properties, has also been shown to reduce restenosis in previous clinical trials. Recent experimental studies have suggested potential synergy between probucol and cilostazol in preventing atherosclerosis, possibly by suppressing inflammatory reactions and promoting cholesterol efflux. Methods/design The Synergistic Effect of combination therapy with Cilostazol and probUcol on plaque stabilization and lesion REgression (SECURE) study is designed as a double-blind, randomised, controlled, multicenter clinical trial to investigate the effect of cilostazol and probucol combination therapy on plaque volume and composition in comparison with cilostazol monotherapy using intravascular ultrasound and Virtual Histology. The primary end point is the change in the plaque volume of index intermediate lesions between baseline and 9-month follow-up. Secondary endpoints include change in plaque composition, neointimal growth after implantation of stents at percutaneous coronary intervention target lesions, and serum levels of lipid components and biomarkers related to atherosclerosis and inflammation. A total of 118 patients will be included in the study. Discussion The SECURE study will deliver important information on the effects of combination therapy on lipid composition and biomarkers related to atherosclerosis, thereby providing insight into the mechanisms underlying the prevention of atherosclerosis progression by cilostazol and probucol. Trial registration number ClinicalTrials (NCT): NCT01031667

2011-01-01

203

Determinants of job satisfaction among radiation therapy faculty.  

PubMed

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. PMID:19753428

Swafford, Larry G; Legg, Jeffrey S

2009-01-01

204

Transformation of lymphoma to amyloidoma following radiation therapy  

SciTech Connect

A 62-year-old man presented with a localized upper-extremity small cell lymphoma with plasmacytoid features and an associated IgM lambda serum immunoglobulin level of 1,730 g/dl. The tumor was treated with 5,960 rad over 47 days. On completion of radiation therapy, the tumor had regressed only minimally, and the monoclonal immunoglobulin level had decreased by 63 per cent; repeat biopsy revealed that the lymphoma had been replaced by a virtually acellular mass of amyloid. It is postulated that radiation therapy accelerated the tissue conversion of lambda light chain into the beta-pleated sheet structure characteristic of amyloid fibrils.

Levitan, N.; Rubinow, A.; Bromer, R.H.; Conlon, C.L.; Doos, W.G.; Hong, W.K.

1985-10-01

205

Complications of head and neck radiation therapy and their management  

SciTech Connect

Patients who receive radiation therapy to the head and neck suffer potential complications and undesirable side-effects of this therapy. The extent of undesirable responses is dependent on the source of irradiation, the fields of irradiation, and the dose. The radiotherapist determines these factors by the extent, location, and radiosensitivity of the tumor. The potential undesirable side-effects are xerostomia, mucositis, fibrosis, trismus, dermatitis, photosensitivity, radiation caries, soft tissue necrosis, and osteoradionecrosis. Each of these clinical entities and their proposed management have been discussed.

Engelmeier, R.L.; King, G.E.

1983-04-01

206

Radiation therapy in the management of breast cancer.  

PubMed

Radiation therapy (RT) plays an essential role in the management of breast cancer by eradicating subclinical disease after surgical removal of grossly evident tumor. Radiation reduces local recurrence rates and increases breast cancer-specific survival in patients with early-stage breast cancer after breast-conserving surgery and in node-positive patients who have undergone mastectomy. This article reviews the following topics: (1) the rationale for adjuvant RT and the evidence for its use in noninvasive and invasive breast cancer, (2) RT delivery techniques for breast-conserving therapy such as hypofractionated RT, partial breast irradiation, and prone irradiation, and (3) indications for PMRT. PMID:23464696

Yang, T Jonathan; Ho, Alice Y

2013-04-01

207

Management of Chemotherapeutic Agent Extravasation and Radiation Therapy Adverse Effects  

Microsoft Academic Search

\\u000a Although chemotherapy and radiation therapy are very effective modalities against cancer, both of these powerful therapies\\u000a can have significant adverse effects on oncology patients. Chemotherapeutic agents can extravasate from veins, damaging nearby\\u000a tissues, whereas therapeutic irradiation also can cause extensive tissue damage. Each member of the healthcare team should\\u000a recognize and help to prevent these complications among oncology patients. Furthermore,

Ida K. Fox; Howard N. Langstein

208

Radiation beam therapy evolution: From X-rays to hadrons  

SciTech Connect

The history of external radiation beam therapy (radiotherapy)-in particular, proton therapy (PT)-is brietly outlined. Two possible strategies in increasing the efficacy of radiotherapy are considered. The radiotherapy methods and techniques are brietly described. The possibilities of PT in providing effective treatment and the main achievements are demonstrated. The state of the art in the PT development involving the active creation of large clinical PT centers since 1990 is analyzed.

Khoroshkov, V. S. [Institute of Theoretical and Experimental Physics (Russian Federation)], E-mail: khoroshkov@itep.ru

2006-10-15

209

Clinical efficacy of respiratory gated conformal radiation therapy  

Microsoft Academic Search

One major limitation of three-dimensional conformal radiation therapy that has not been adequately addressed is respiration-induced organ motion. During respiration, tumors in the abdomen can typically move from 1 to 3 centimeters. Because the size and shape of external radiation treatment fields do not change during treatment, the field size of the x-ray beam must be enlarged to encompass the

Chester R Ramsey; Daniel Scaperoth; Don Arwood; Adrian L Oliver

1999-01-01

210

Quality assurance in radiation therapy: physical aspects  

Microsoft Academic Search

The present status of the quality assurance work regarding the physical aspects in radiation treatment is discussed. In particular, the situation in Europe is surveyed. An analysis of the errors in the delivered absorbed dose to a specified point in the irradiated patient shows that the uncertainty, to approximately the same degree, depends on the dose distribution determination, the dose

Hans Svensson

1984-01-01

211

Episcleral plaque thermoradiotherapy of posterior uveal melanomas.  

PubMed

Episcleral plaque radiotherapy is a widely applied treatment for selected patients with uveal melanomas. This treatment is well tolerated but may produce severe late radiation complications resulting in decreased visual acuity that reduces the attractiveness of conservative therapy. The purpose of this study was to access if the addition of episcleral hyperthermia decreases late radiation complications through radiation dose reduction while maintaining high incidence of local tumor control. In a 3-year period, episcleral plaque thermoradiotherapy was given to 25 patients with uveal melanoma in a Phase I study. The mean tumor height was 6.2 mm and the mean tumor basal area was 173 mm(2). The mean radiation dose given to the tumor apex was 72.2 Gy and the mean hyperthermia temperature, given once for 45 min, was 43.5 degrees C. Of the 25 patients treated, 22 (88%) showed tumor height reduction, 2 (8%) showed no change, and 1 (4%) had an increase in tumor height. At the last follow-up (range, 20-68 months; mean, 31.2 months), a 43% mean tumor height reduction was recorded (p = 0.0002). Of the 22 patients initially showing tumor regression, 2 (9%) had subsequent tumor progression. At least ambulatory vision (>5/200) was maintained by 20 (80%) patients. Severe complications, including hemorrhagic retinal detachment and a large vitreous hemorrhage, were seen in 2 (8%) patients early in this Phase I study. The treatment program was well tolerated by the study patients. Severe late treatment toxicity was sharply reduced by limiting the mean scleral temperature to < or equal to 44 degrees C. This study employing 30% lower radiation doses, showed tumor regression in the majority of patients. Longer follow-up is needed to assess long-term treatment efficacy and late treatment complications. PMID:8610652

Petrovich, Z; Pike, M; Astrahan, M A; Luxton, G; Murphree, A L; Liggett, P E

1996-04-01

212

Health-related quality-of-life after external beam radiation therapy for localized prostate cancer: intensity-modulated radiation therapy versus conformal radiation therapy  

Microsoft Academic Search

We compared health-related quality-of-life (HRQL) after intensity-modulated radiotherapy (IMRT) with statuses obtained after old and new protocols of three-dimensional conformal radiation therapy (3DCRT) for localized prostate cancer. We measured the general and disease specific HRQL using the MOS 36-Item Health Survey (SF-36), and the University of California, Los Angeles Prostate Cancer Index (UCLA PCI), respectively. IMRT resulted in similar profiles

K Yoshimura; T Kamoto; E Nakamura; T Segawa; T Kamba; T Takahashi; H Nishiyama; N Ito; K Takayama; T Mizowaki; M Mitsumori; M Hiraoka; O Ogawa

2007-01-01

213

Maxillary sinus carcinoma: result of radiation therapy  

SciTech Connect

This hundred and sixteen patients with carcinoma of the maxillary sinus received primary therapy consisting of external beam irradiation alone or in combination with surgery and/or chemotherapy at the Department of Radiology, Tokyo Medical and Dental University Hospital, between 1953 and 1982. In our institution, methods of treating cancer of the maxillary sinus have been changed from time to time and showed different control rates and clinical courses. An actuarial 10-year survival rate of 21% has been obtained by the megavoltage irradiation alone as well as 34% actuarial 10-year survival rate by megavoltage irradiation with surgery. After the introduction of conservative surgery followed by conventional trimodal combination therapy, the local control rate has been improved. The amount of functional, cosmetic, and brain damages have been remarkably decreased by this mode of therapy. The actuarial five year survival rate was 67%. In addition, along with the improvement of the local control rate, the control of nodal and distant organ metastases have been emerging as one of the important contributions to the prognosis of this disease.

Shibuya, H.; Horiuchi, J.; Suzuki, S.; Shioda, S.; Enomoto, S.

1984-07-01

214

Phototherapy cabinet for ultraviolet radiation therapy  

SciTech Connect

A newly designed cabinet can be used for the treatment of psoriasis with fluorescent ultraviolet (UV) lamps. the new design provides more uniform distribution of UV radiation in both the horizontal and vertical axes, and several safety features have been added. The distribution and uniformity of UV output in this and in a previously described cabinet are compared. The UV output at the vertical center of the older UV light cabinet was six times greater than that at either the top or bottom, while the design of the present cabinet provides uniform UV radiation except for a slight increase at head height and at the level of the lower legs compared with the middle third of the cabinet. The variation in output of the older cabinet may, in part, explain the commonly encountered difficulty in the phototherapy of psoriasis of the scalp and lower extremities.

Horwitz, S.N.; Frost, P.

1981-08-01

215

Waiting Lists for Radiation Therapy: A Case Study  

PubMed Central

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.

D'Souza, David P; Martin, Douglas K; Purdy, Laura; Bezjak, Andrea; Singer, Peter A

2001-01-01

216

Measuring patient satisfaction with radiation therapy service delivery  

Microsoft Academic Search

Patient satisfaction is an important component in the evaluation of health services provided to patients. This study evaluates the results of a patient satisfaction survey collected over five years in a radiation therapy department. The analysis identifies that satisfaction has improved in almost all areas, but there is room for improvement in others. The key findings are the importance of

John French; Colleen McGahan

2009-01-01

217

Hypofractionated stereotactic body radiation therapy (SBRT) for limited hepatic metastases  

Microsoft Academic Search

Purpose: To evaluate the feasibility and efficacy of hypofractionated stereotactic body radiation therapy (SBRT) for the treatment of liver metastases. Methods and Materials: The records of 69 patients with 174 metastatic liver lesions treated with SBRT between April 2001 and October 2004 were reviewed. The most common primary tumors were colorectal (n = 20), breast (n = 16), pancreas (n

Alan W.. Katz; Madeleine Carey-Sampson; Ann G. Muhs; Michael T. Milano; Michael C. Schell; Paul Okunieff

2007-01-01

218

SMART: Stroke-Like Migraine Attacks After Radiation Therapy  

Microsoft Academic Search

We describe two adults with stroke-like migraine attacks after radiation therapy (SMART syndrome), propose revised diagnostic criteria, and review the previously reported patients. SMART is an acronym for a newly recognized syndrome which occurs as a delayed consequence of cerebral irradiation and consists of prolonged, unilateral, migrainous neurological symptoms with transient, dramatic cortical gadolinium enhancement of the affected cerebral hemisphere

DF Black; JD Bartleson; ML Bell; DH Lachance

2006-01-01

219

Pediatric meuroblastoma: postoperative radiation therapy using less than 2000 rad  

Microsoft Academic Search

There is considerable controversy regarding the role of radiaiton therapy in the treatment of neuroblastoma. Postoperative irradiation in the range of 2500-4000 rad is commonly used in the treatment of Evans Stage II or III disease, but there are no data in the literature to suggest the optimum dose of radiation that is necessary. Because much lower doses have been

Hal M. Jacobson; Robert B. Marcus Jr.; Timothy L. Thar; Rodney R. Million; John R. Graham-Pole; James L. Talbert

1983-01-01

220

Radiation Therapy Services: Health Systems Plan and Appropriateness Review.  

National Technical Information Service (NTIS)

The bulk of this document consists of standards for use in appropriateness review of megavoltage radiation therapy services. The six standards specify: (1) a service population of 150,000 per machine; (2) annual caseload of 200 patients per machine, to be...

1981-01-01

221

Radiation therapy in the management of patients with mesothelioma  

SciTech Connect

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 of 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.

Gordon, W. Jr.; Antman, K.H.; Greenberger, J.S.; Weichselbaum, R.R.; Chaffey, J.T.

1982-01-01

222

High contrast, CdTe portal scanner for radiation therapy  

Microsoft Academic Search

One of the most promising technologies for improving the quality of radiation therapy is the use of real-time systems to produce portal images. A linear array of 256 CdTe photovoltaic detectors attached to a very compact linear scanner, all of which will be mounted in a cassette shaped package to be located under the patient table, is being constructed. The

G. Entine; M. R. Squillante; R. Hahn; L. J. Cirignano; W. McGann; P. I. Biggs

1991-01-01

223

Radiation and the Microenvironment - Tumorigenesis andTherapy  

SciTech Connect

Radiation rapidly and persistently alters the soluble and insoluble components of the tissue microenvironment. This affects the cell phenotype, tissue composition and the physical interactions and signaling between cells. These alterations in the microenvironment can contribute to carcinogenesis and alter the tissue response to anticancer therapy. Examples of these responses and their implications are discussed with a view to therapeutic intervention.

Barcellos-Hoff, Mary Helen; Park, Catherine; Wright, Eric G.

2005-10-01

224

Erlotinib: An enhancer of radiation therapy in nasopharyngeal carcinoma  

PubMed Central

The aim of this study was to explore the effects of erlotinib combined with radiation on human nasopharyngeal carcinoma (NPC) radiosensitivity using the CNE1 and CNE2 cell lines. Human NPC cells were treated with erlotinib and/or radiation. The effect of erlotinib on the radiosensitivity of the cells was detected using a clonogenic cell survival assay. The rate of apoptosis and the cell cycle were evaluated using flow cytometry. An NPC xenograft model in NOD-SCID mice was used to evaluate the efficacy of the combination therapy of erlotinib with radiation. Erlotinib enhanced the sensitivity of the CNE1 and CNE2 cells to radiation, with sensitization enhancement ratios (SERs) of 1.076 and 1.109, respectively. Erlotinib combined with radiation induced G2/M phase cell cycle arrest in the two cell lines. The mouse tumor model demonstrated a significant reduction in NPC tumor volume in mice treated with erlotinib in combination with radiation when compared with that in mice treated with radiation alone. Erlotinib combined with radiation provoked G2-M phase cell cycle arrest, thereby enhancing the sensitivity of the NPC cells to radiation.

ZHANG, HUAN-HUAN; YUAN, TAI-ZE; LI, JIAN; LIANG, YIN; HUANG, LAI-JI; YE, JIA-CAI; ZHENG, RONG-HUI; XIE, GUO-FENG; ZHANG, XIU-PING

2013-01-01

225

Fiber-optic Cerenkov radiation sensor for proton therapy dosimetry.  

PubMed

In proton therapy dosimetry, a fiber-optic radiation sensor incorporating a scintillator must undergo complicated correction processes due to the quenching effect of the scintillator. To overcome the drawbacks of the fiber-optic radiation sensor, we proposed an innovative method using the Cerenkov radiation generated in plastic optical fibers. In this study, we fabricated a fiber-optic Cerenkov radiation sensor without an organic scintillator to measure Cerenkov radiation induced by therapeutic proton beams. Bragg peaks and spread-out Bragg peaks of proton beams were measured using the fiber-optic Cerenkov radiation sensor and the results were compared with those of an ionization chamber and a fiber-optic radiation sensor incorporating an organic scintillator. From the results, we could obtain the Bragg peak and the spread-out Bragg peak of proton beams without quenching effects induced by the scintillator, and these results were in good agreement with those of the ionization chamber. We also measured the Cerenkov radiation generated from the fiber-optic Cerenkov radiation sensor as a function of the dose rate of the proton beam. PMID:22714456

Jang, Kyoung Won; Yoo, Wook Jae; Shin, Sang Hun; Shin, Dongho; Lee, Bongsoo

2012-06-18

226

Radiation therapy for primary optic nerve meningiomas  

SciTech Connect

Optic nerve sheath meningiomas, formerly thought to be rare, have been encountered with surprising frequency since the widespread use of computed tomography. Early diagnosis led to an enthusiastic surgical approach to these lesions, but this has been tempered by the realization that even in the best of hands, blindness followed such surgery with distressing frequency. Optic nerve sheath meningiomas may be divided into primary, secondary, and multiple meningioma groups. Five patients with primary optic nerve sheath meningiomas treated with irradiation therapy are presented in this report. Improvement in visual acuity, stabilization to increase in the visual field, and decrease in size to total regression of optociliary veins, have been documented following irradiation therapy of the posterior orbital and intracanalicular portions of the optic nerve in some of these cases. Although each patient must be carefully individualized, there is no question that visual palliation can be achieved in some cases of optic nerve sheath meningioma. Further investigation of this therapeutic modality in selected cases in advised.

Smith, J.L.; Vuksanovic, M.M.; Yates, B.M.; Bienfang, D.C.

1981-06-01

227

Research Findings on Radiation Hormesis and Radon Therapy  

SciTech Connect

Radiation hormesis research in Japan to determine the validity of Luckey's claims has revealed information on the health effects of low-level radiation. The scientific data of animal tests we obtained and successful results actually brought by radon therapy on human patients show us a clearer understanding of the health effects of low-level radiation. We obtained many animal test results and epidemiological survey data through our research activities cooperating with more than ten universities in Japan, categorized as follows: 1. suppression of cancer by enhancement of the immune system based on gene activation; 2. rejuvenation and suppression of aging by increasing cell membrane permeability and enzyme syntheses; 3. adaptive response by activation of gene expression on DNA repair and cell apoptosis; 4. pain relief and stress moderation by hormone formation in the brain and central nervous system; 5. avoidance and therapy of obstinate diseases by enhancing damage control systems and form one formation.

Hattori, Sadao

1999-06-06

228

Backgrounds of computer-assisted treatment planning in radiation therapy.  

PubMed

Interaction of ionising radiation and living materials causes biological damage of tempory or permanent nature. In radiation therapy this phenomenon is used in a controlled fashion in order to stop the proliferation of malignant cells, while at the same time limiting the permanent damage to healthy tissues and organs to at least tolerable levels. Because of the often relatively small differences in response of malignant growths and normal tissues, the margins between tolerable and intolerable are so small that the greatest precision in treatment planning and execution is required. The nature of this treatment agent implies that the radiation therapist has to rely very much on instrumentally obtained and processed information, in all phases of this medical activities around the patient. In this paper a description is given of the backgrounds of computer-assisted methods which have enabled modern individualised and optimised planning for therapy with high enery X - and gamma beams. PMID:1178845

van de Geijn, J

1975-06-01

229

Review and Uses of Stereotactic Body Radiation Therapy for Oligometastases  

PubMed Central

In patients with proven distant metastases from solid tumors, it has been a notion that the condition is incurable, warranting palliative care only. The term oligometastases was coined to refer to isolated sites of metastasis, whereby the entire burden of disease can be recognized as a finite number of discrete lesions that can be potentially cured with local therapies. Stereotactic body radiation therapy (SBRT) is a novel treatment modality in radiation oncology that delivers a very high dose of radiation to the tumor target with high precision using single or a small number of fractions. SBRT is the result of technological advances in patient and tumor immobilization, image guidance, and treatment planning and delivery. A number of studies, both retrospective and prospective, showed promising results in terms of local tumor control and, in a limited subset of patients, of survival. This article reviews the radiobiologic, technical, and clinical aspects of SBRT for various anatomical sites.

Alongi, Filippo; Filippi, Andrea Riccardo; Ricardi, Umberto; Scorsetti, Marta

2012-01-01

230

The effects of sequence and type of chemotherapy and radiation therapy on cosmesis and complications after breast conservation therapy  

Microsoft Academic Search

Purpose|: Chemotherapy plays an increasingly important role in the treatment of both node-negative and node-positive positive breast cancer partients, but the optimal sequencing of chemotherapy and radiation therapy is not well established. The purpose of this study is to evaluate the interaction of sequence and type of chemotherapy and hormonal therapy given with radiation therapy on the cosmetic outcome and

Deborah A. Markiewicz; Delray J. Schultz; Jonathan A. Haas; Eleanor E. R. Harris; Kevin R. Fox; John H. Glick; Lawrence J. Solin

1996-01-01

231

Management of high-risk prostate cancer: radiation therapy and hormonal therapy.  

PubMed

The prognosis of high-risk prostate cancer is poor with a high mortality rate. The Radiation Therapy Oncology Group (RTOG) has performed dose-escalation studies of external beam radiation therapy (EBRT) and has developed high-precision radiation therapy (RT) methods such as intensity-modulated RT, carbon ion therapy, and proton beam therapy. High-dose rate brachytherapy (HDR-BT) is also studied as an option for high-risk prostate cancer treatment. Past clinical trials have suggested that the local control rate of high-risk prostate cancer improves with total EBRT dose, even for doses > 70 Gy. Several randomized controlled trials, including RTOG 94-06, have shown significantly better prognoses with higher doses (> 75 Gy) than with lower doses (< 70 Gy). A proton beam therapy trial (PROG 95-09) also showed similar results. A phase II clinical trial (National Institute for Radiological Sciences, Japan; trial 9904) showed that carbon ion therapy resulted in very good biochemical recurrence-free survival rates among high-risk prostate cancer patients, demonstrating particle therapy to be a valid treatment option. RTOG 86-10 showed that short-term neo-adjuvant hormonal therapy (HT) was inadequate for high-risk prostate cancer but effective for intermediate-risk prostate cancer, whereas RTOG 92-02 and the European Organisation for Research and Treatment of Cancer (EORTC) 22863 showed significant improvements in the prognosis of high-risk groups receiving long-term (> 2 years) HT combined with definitive RT. Further studies are warranted to elucidate optimal irradiation doses, HT treatment durations, and combination therapy schedules. PMID:23648323

Nomiya, Takuma; Tsuji, Hiroshi; Toyama, Shingo; Maruyama, Katsuya; Nemoto, Kenji; Tsujii, Hirohiko; Kamada, Tadashi

2013-05-03

232

Managing Radiation Therapy Side Effects: What Men Can Do about Changes in Sexuality and Fertility  

MedlinePLUS

... talk with your doctor. Questions from men getting radiation therapy to the pelvic area: Will I still be ... method should be used. Questions from men getting radiation therapy Is it okay to have sex? This is ...

233

Managing Radiation Therapy Side Effects: What to Do about Mild Skin Changes  

MedlinePLUS

... AND HUMAN SERVICES National Institutes of Health Managing Radiation Therapy Side Effects What To Do About Mild Skin ... nurse how to care for these areas. Managing Radiation Therapy Side Effects:What To Do About Mild Skin ...

234

What to Know about Brachytherapy (A Type of Internal Radiation Therapy)  

MedlinePLUS

... To Know About Brachytherapy (A Type of Internal Radiation Therapy) I asked questions. My doctor took the time ... the part of your body being treated with radiation therapy. See the back of this sheet to order ...

235

Managing Radiation Therapy Side Effects: What to Do When Your Mouth or Throat Hurts  

MedlinePLUS

... AND HUMAN SERVICES National Institutes of Health Managing Radiation Therapy Side Effects What To Do When Your Mouth ... I take to help stop the pain? Managing Radiation Therapy Side Effects:What To Do When Your Mouth ...

236

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

Code of Federal Regulations, 2010 CFR

...5050 Medical charged-particle radiation therapy system...Identification. A medical charged-particle radiation therapy system...acceleration high energy charged particles (e.g., electrons and protons)...

2009-04-01

237

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

Code of Federal Regulations, 2010 CFR

...5050 Medical charged-particle radiation therapy system...Identification. A medical charged-particle radiation therapy system...acceleration high energy charged particles (e.g., electrons and protons)...

2010-04-01

238

Study of digital image processing system using a sensor for therapy radiation.  

National Technical Information Service (NTIS)

Near real time digital radiography system was implemented for verification of local error between simulation plan and radiation therapy machine. After therapy radiation was converted into light by a metal /fluorescent screen, portal image can be acquired ...

D. H. Lee Y. H. Ji D. H. Lee J. S. Chai Y. S. Kim

1997-01-01

239

Quality assurance in radiation therapy: physical aspects  

SciTech Connect

The present status of the quality assurance work regarding the physical aspects in radiation treatment is discussed. In particular, the situation in Europe is surveyed. An analysis of the errors in the delivered absorbed dose to a specified point in the irradiated patient shows that the uncertainty, to approximately the same degree, depends on the dose distribution determination, the dose planning and the patient irradiation. Following the procedure generally in use, the overall uncertainty will be about 8%. The random uncertainties are estimated as one standard deviation and non-random uncertainties to corresponding degree of uncertainty. It is argued that this level must be improved. Furthermore, dose intercomparisons show that in reality much larger errors occur in clinical practice. Different means to improve the situation are discussed.

Svensson, H.

1984-06-01

240

Stereotactic Body Radiation Therapy in Spinal Metastases  

SciTech Connect

Purpose: Based on reports of safety and efficacy, stereotactic body radiotherapy (SBRT) for treatment of malignant spinal tumors was initiated at our institution. We report prospective results of this population at Mayo Clinic. Materials and Methods: Between April 2008 and December 2010, 85 lesions in 66 patients were treated with SBRT for spinal metastases. Twenty-two lesions (25.8%) were treated for recurrence after prior radiotherapy (RT). The mean age of patients was 56.8 {+-} 13.4 years. Patients were treated to a median dose of 24 Gy (range, 10-40 Gy) in a median of three fractions (range, 1-5). Radiation was delivered with intensity-modulated radiotherapy (IMRT) and prescribed to cover 80% of the planning target volume (PTV) with organs at risk such as the spinal cord taking priority over PTV coverage. Results: Tumor sites included 48, 22, 12, and 3 in the thoracic, lumbar, cervical, and sacral spine, respectively. The mean actuarial survival at 12 months was 52.2%. A total of 7 patients had both local and marginal failure, 1 patient experienced marginal but not local failure, and 1 patient had local failure only. Actuarial local control at 1 year was 83.3% and 91.2% in patients with and without prior RT. The median dose delivered to patients who experienced local/marginal failure was 24 Gy (range, 18-30 Gy) in a median of three fractions (range, 1-5). No cases of Grade 4 toxicity were reported. In 1 of 2 patients experiencing Grade 3 toxicity, SBRT was given after previous radiation. Conclusion: The results indicate SBRT to be an effective measure to achieve local control in spinal metastases. Toxicity of treatment was rare, including those previously irradiated. Our results appear comparable to previous reports analyzing spine SBRT. Further research is needed to determine optimum dose and fractionation to further improve local control and prevent toxicity.

Ahmed, Kamran A. [Mayo Medical School, College of Medicine, Mayo Clinic, Rochester, MN (United States); Stauder, Michael C.; Miller, Robert C.; Bauer, Heather J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Rose, Peter S. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN (United States); Olivier, Kenneth R. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Brinkmann, Debra H. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Laack, Nadia N., E-mail: laack.nadia@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

2012-04-01

241

Stereotactic Body Radiation Therapy for Patients With Lung Cancer Previously Treated With Thoracic Radiation  

SciTech Connect

Purpose: Stereotactic body radiation therapy (SBRT) provides excellent local control with acceptable toxicity for patients with early-stage non-small cell lung cancer. However, the efficacy and safety of SBRT for patients previously given thoracic radiation therapy is not known. In this study, we retrospectively reviewed outcomes after SBRT for recurrent disease among patients previously given radiation therapy to the chest. Materials and Methods: A search of medical records for patients treated with SBRT to the thorax after prior fractionated radiation therapy to the chest at The University of Texas M. D. Anderson Cancer Center revealed 36 such cases. The median follow-up time after SBRT was 15 months. The endpoints analyzed were overall survival, local control, and the incidence and severity of treatment-related toxicity. Results: SBRT provided in-field local control for 92% of patients; at 2 years, the actuarial overall survival rate was 59%, and the actuarial progression-free survival rate was 26%, with the primary site of failure being intrathoracic relapse. Fifty percent of patients experienced worsening of dyspnea after SBRT, with 19% requiring oxygen supplementation; 30% of patients experienced chest wall pain and 8% Grade 3 esophagitis. No Grade 4 or 5 toxic effects were noted. Conclusions: SBRT can provide excellent in-field tumor control in patients who have received prior radiation therapy. Toxicity was significant but manageable. The high rate of intrathoracic failure indicates the need for further study to identify patients who would derive the most benefit from SBRT for this purpose.

Kelly, Patrick [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Balter, Peter A. [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Rebueno, Neal; Sharp, Hadley J.; Liao Zhongxing; Komaki, Ritsuko [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Chang, Joe Y., E-mail: jychang@mdanderson.or [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

2010-12-01

242

Dose to normal tissues outside the radiation therapy patient's treated volume: a review of different radiation therapy techniques.  

PubMed

Radiation therapy treatment planning and delivery capabilities have changed dramatically since the introduction of three-dimensional treatment planning and are continuing to change relatively rapidly in response to the implementation of new advanced technologies. Three-dimensional conformal radiation therapy (3DCRT) is now firmly in place as the standard of practice in clinics around the world. Medical accelerator manufacturers have employed advanced computer technology to produce treatment planning/delivery systems capable of precise shaping of dose distributions via computer-controlled multileaf collimator (MLC) systems, by which the beam fluence is varied optimally to achieve the desired dose distribution. This mode of conformal therapy is referred to as intensity modulated radiation therapy (IMRT), and is capable of generating dose distributions (including concave isodose volumes) that closely conform the prescription dose to the target volume and/or avoid specific sensitive normal structures. The increasing use of IMRT has focused attention on the need to better account for the intra- and inter-fraction spatial uncertainties in the dose delivery process. This has helped spur the development of treatment machines with integrated planar and volumetric advanced imaging capabilities, providing a new treatment modality referred to as image-guided IMRT (IG-IMRT), or simply image-guided radiation therapy (IGRT). In addition, there is a growing interest in replacing x rays with protons because of the physical characteristics of the depth dose curve, which peaks at the end of particle range, and eventually with even heavier charged particles to take advantage of the greater density of energy deposition close to the Bragg peak and hence larger relative biological effectiveness (RBE). Three-dimensional CRT, IMRT and proton beam therapy all provide improved target coverage and lower doses to surrounding normal tissues as compared to the previously used two-dimensional radiation therapy techniques. However, this is achieved at the expense of a greater volume of normal tissue in the irradiated volume receiving some dose and a higher whole body dose (or peripheral dose) to distant normal tissues. The higher whole body dose is a result of the increased x-ray leakage radiation to the patient due to the longer beam-on times associated with IMRT, and also from neutron leakage radiation associated with high energy x-ray beams (>10 MV) and proton beams. Dose distributions for the various CRT techniques and the current status of available data for normal tissues, and whole body dose are reviewed. PMID:18849701

Purdy, James A

2008-11-01

243

Stem cell therapy remediates reconstruction of the craniofacial skeleton after radiation therapy.  

PubMed

This study utilized transplanted bone marrow stromal cells (BMSCs) as a cellular replacement therapy to remedy radiation-induced injury and restore impaired new bone formation during distraction osteogenesis (DO). BMSC therapy brought about the successful generation of new bone and significantly improved both the rate and quality of a bony union of irradiated, distracted [X-ray radiation therapy (XRT)/DO] murine mandibles to the level of nonirradiated DO animals. The bone mineral density and bone volume fraction were also significantly improved by the BMSC replacement therapy showing no difference when compared to nonirradiated animals. Finally, a biomechanical analysis examining the yield, failure load, and ultimate load also demonstrated a significantly improved structural integrity in BMSC-treated XRT/DO mandibles over XRT/DO alone. These results indicate that administration of BMSCs intraoperatively to a radiated distraction gap can function as an adequate stimulant to rescue the ability for irradiated bone to undergo DO and produce a healed regenerate of a vastly superior quality and strength. We believe that the fundamental information on the optimization of bone regeneration in the irradiated mandible provided by this work has immense potential to be translated from the bench to the bedside to lead to improved therapeutic options for patients suffering from the disastrous sequelae of radiation therapy. PMID:23282102

Deshpande, Sagar S; Gallagher, Kathleen K; Donneys, Alexis; Tchanque-Fossuo, Catherine N; Sarhaddi, Deniz; Sun, Hongli; Krebsbach, Paul H; Buchman, Steven R

2013-02-19

244

[The application of total quality management (TQM) in quality management of radiation therapy].  

PubMed

The strategies and methods of the total quality management (TQM) need to applied in quality management of radiation therapy. We should improve the level of quality control and quality assurance in radiation therapy. By establishing quality control system in radiation therapy, standardization of radiation therapy workflow, strengthening quality control of devices and physical technique and paying attention to safety protection and staff training. PMID:19565799

Jiang, Rui-yao; Fu, Shen; Li, Bin

2009-03-01

245

Hormone replacement therapy use is associated with a lower occurrence of carotid atherosclerotic plaques but not with intima-media thickness progression among postmenopausal women. The vascular aging (EVA) study  

Microsoft Academic Search

Background: Information on the impact of hormone replacement therapy (HRT) on carotid atherosclerosis is limited. Moreover, transdermal estrogens have not been investigated. Methods: We examined association of HRT use with ultrasonographically assessed carotid atherosclerotic plaque occurrence and mean common carotid artery intima-media thickness (CCAIMT) progression. Within the Vascular Aging (EVA) Study, a community-based cohort, 815 postmenopausal women aged 5971 have

Grgoire Le Gal; Vronique Gourlet; Patricia Hogrel; Genevive Plu-Bureau; Pierre-Jean Touboul; Pierre-Yves Scarabin

2003-01-01

246

Internal dosimetry for systemic radiation therapy  

SciTech Connect

The key to effective use of the medical internal radiation dose (MIRD) schema in radioimmunotherapy (RIT) is to understand how it works and what the essential data input requirements are. The fundamental data are acquired from medical imaging. Image interpretation involves (1) collecting data to determine the source-organ activities, (2) plotting the source-organ time-activity curves, (3) integrating the time-activity curves for an estimate of the residence time, and (4) applying the residence time values (for each important source organ) within the MIRD schema to calculate the tissue absorbed dose to target organs and tumors of interest. This article reviews methods for calculating internal dose. It also describes methods for selecting sampling times, integrating the area under the data curves, and customizing a dose assessment for a patient who does not resemble the MIRD phantom. A sample dose assessment is given, together with common mistakes to avoid. Three approaches to red marrow dosimetry are described. With the increased use of RIT agents for cancer treatment, a solid understanding of internal dose methods is essential for treatment planning and follow-up evaluations.

Fisher, Darrell R. (BATTELLE (PACIFIC NW LAB))

1999-12-01

247

21 CFR 892.5900 - X-ray radiation therapy system.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false X-ray radiation therapy system. 892.5900 Section...Therapeutic Devices § 892.5900 X-ray radiation therapy system. (a) Identification. An x-ray radiation therapy system is a device...

2013-04-01

248

Data handling in radiation therapy in the age of image-guided radiation therapy.  

PubMed

Image-guided radiation therapy (IGRT) in the modern sense includes large volumetric image sets and high-resolution planar images. In addition to the issue of the sheer size of the data under consideration in IGRT is the critical need for the data to be available in the necessary situation in a timely and reliable fashion. Standards exist for the format of much of the data needed to perform IGRT, but the information workflow is not "standardized" (formal or ad hoc) and details of the use of the standards are only recently being constrained to ensure interoperability. Depending on the interpretation of the scope of IGRT or the desired workflow of the IGRT system, not all of the information that needs to be exchanged between systems is yet standardized nor is the means to exchange the information. The organization of the different types of data needed for IGRT for easy navigation is addressed by commercially available products from multiple vendors; however, this is also an area in which standards and consistency in the clinical environment are catching up to the market. The critical questions a clinician needs answers to include the following: (1) What kinds of data will I need to store and communicate between the pieces of my IGRT system? (2) How much storage will I need to address the volumes of data produced? (3) How long do I need to store (and be able to access) the data? (4) How will the pieces of my IGRT system communicate the necessary information between them (what standards or technical frameworks apply and do the pieces conform or adhere to them)? (5) What are the time constraints on getting information from "where it is" to "where it needs to be"? and (6) Is my IGRT system as a whole capable of providing me with the workflow necessary for my clinical environment or, alternatively, what do the providers of my IGRT system need to do to enable my required workflow? The body of this article examines these issues in greater detail to enable clinicians and clinical support personnel to frame the questions in a practical manner and develop answers that assist in the successful deployment of IGRT. PMID:17903706

Swerdloff, Stuart J

2007-10-01

249

Shielding and Radiation Protection in Ion Beam Therapy Facilities  

NASA Astrophysics Data System (ADS)

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.

Wroe, Andrew J.; Rightnar, Steven

250

Review How to evaluate plaque vulnerability in animal models of atherosclerosis?  

Microsoft Academic Search

Prevention of heart attack and stroke depends on detection of vulnerable plaques and development of plaque-stabilizing therapies. In turn, progress in diagnostics and treatment is contingent on our understanding of molecular mechanisms of plaque vulnerability. Animal models are essential for testing mechanistic hypotheses in a controlled manner. Currently, there is no single, golden standard animal model of a vulnerable plaque.

Mark D. Rekhter

251

Stereotactic body radiation therapy for metastasis to the adrenal glands.  

PubMed

Many primary cancers can metastasize to the adrenal glands. Adrenalectomy via an open or laparoscopic approach is the current definitive treatment, but not all patients are eligible or wish to undergo surgery. There are only limited studies on the use of conventional radiation therapy for palliation of symptoms from adrenal metastasis. However, the advent of stereotactic body radiation therapy (SBRT) - also named stereotactic ablative radiotherapy for primary lung cancer, metastases to the lung, and metastases to the liver - have prompted some investigators to consider the use of SBRT for metastases to the adrenal glands. This review focuses on the emerging data on SBRT of metastasis to the adrenal glands, while also providing a brief discussion of the overall management of adrenal metastasis. PMID:23253226

Shiue, Kevin; Song, Andrew; Teh, Bin S; Ellis, Rodney J; Yao, Min; Mayr, Nina A; Huang, Zhibin; Sohn, Jason; Machtay, Mitchell; Lo, Simon S

2012-12-01

252

Sick sinus syndrome as a complication of mediastinal radiation therapy  

SciTech Connect

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.

Pohjola-Sintonen, S.; Toetterman, K.J.K.; Kupari, M. (Helsinki Univ. Central Hospital (Finland))

1990-06-01

253

Computerized Treatment Planning Directives for Adaptive Radiation Therapy Management  

Microsoft Academic Search

Treatment planning directives have been developed for radiation therapy process and workflow improvement. Initial plan directives\\u000a were developed on paper forms. These directives have improved our departments workflow based on a lean thinking approach\\u000a to process improvement. Treatment plan directives describe a standard path for each type of case in the belief that standard\\u000a work leads to fewer quality problems,

D. L. McShan; X. Chen; M. L. Kessler; W. M. Keranen; B. A. Fraass

254

Massive osteolysis of the right clavicle developing after radiation therapy  

SciTech Connect

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.

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

1988-07-15

255

Radiation therapy of lymphoblastic renal masses - benefit or hazard  

SciTech Connect

A child with non-Hodgkin lymphoma and massively enlarged kidneys received a single dose of 300 rad (3 Gy) to the right kidney before initiation of chemotherapy. Measurement of the split renal function with 99m-Tc-DTPA four days postirradiation revealed that the function of the right kidney had substantially deteriorated, suggesting that hazards may be involved with the use of radiation therapy for lymphoblastic renal masses.

Saarinen, U.M.

1985-05-01

256

Towards four dimensional (4D) dosimetry for radiation-therapy  

NASA Astrophysics Data System (ADS)

The development of accurate and convenient dosimetry tools with the capacity to comprehensively verify advanced four-dimensional treatments is an important and urgent goal for radiation therapy physicists. At present, implementation into the clinic is being severely hampered and delayed by the difficulty in adequately verifying these techniques using traditional dosimetry methods. The work presented here represents an important step towards providing a solution.

Oldham, M.; Guo, P.; Adamovics, J.; Sakhalkar, H.; Wang, Z.; Yin, Ff

2006-12-01

257

Radiation Therapy Principles for High-Grade Gliomas  

Microsoft Academic Search

\\u000a Gliomas are the most common primary brain tumors,comprising 40-60% of all primary brain tumors.The most frequent types are\\u000a glioblastoma multiforme, astrocytoma, and oligodendroglioma. Radiation therapy is one of the most important treatment modalities\\u000a for gliomas, mainly because these tumors are usually localized. The patients head can be immobilized, allowing for good\\u000a targeting of the tumor. As a result of technological

Curtis Miyamoto

258

Reversible neurotoxicity following hyperfractionated radiation therapy of brain stem glioma  

Microsoft Academic Search

Two patients with brain stem gliomas were treated with hyperfractionated radiation therapy (HFR) (7,020 and 7,560 cGy, respectively). Despite initial clinical improvement during irradiation, both patients demonstrated clinical deterioration approximately 3 weeks after completion of radiotherapy. Cranial magnetic resonance imaging (MRI) revealed a progressive increase in distribution of abnormal brain stem signal consistent with either tumor or edema. ¹⁸FDG positron

Maye Griebel; Henry S. Friedman; Edward C. Halperin; M. David Wiener; Lawrence Marks; W. Jerry Oakes; John M. Hoffman; G. Robert DeLong; S. Clifford Schold; Beverly Hockenberger; Carolyn R. Freeman; Larry Kun

1991-01-01

259

New Algorithm for Field Splitting in Radiation Therapy  

Microsoft Academic Search

In this paper, we study an interesting geometric partition problem, called optimal field splitting, which arises in Intensity-Modulated Radiation Therapy (IMRT). In current clinical practice, a multi-leaf collimator (MLC) is used to deliver the prescribed intensity maps (IMs).\\u000a However, the maximum leaf spread of an MLC may require to split a large intensity map into several overlapping sub-IMs. We develop

Xiaodong Wu; Xin Dou; John E. Bayouth; John M. Buatti

2007-01-01

260

Comparative analysis of 60Co intensity-modulated radiation therapy  

Microsoft Academic Search

In this study, we perform a scientific comparative analysis of using 60Co beams in intensity-modulated radiation therapy (IMRT). In particular, we evaluate the treatment plan quality obtained with (i) 6 MV, 18 MV and 60Co IMRT; (ii) different numbers of static multileaf collimator (MLC) delivered 60Co beams and (iii) a helical tomotherapy 60Co beam geometry. We employ a convex fluence

Christopher Fox; H. Edwin Romeijn; Bart Lynch; Chunhua Men; Dionne M. Aleman; James F. Dempsey

2008-01-01

261

Managing the cognitive effects of brain tumor radiation therapy  

Microsoft Academic Search

Opinion statementPostoperative radiation therapy (RT), either alone or in combination with chemotherapy, is the mainstay of treatment for primary\\u000a and\\/or metastatic brain tumors. The majority of patients with brain tumors will have significant symptoms of their disease\\u000a and of RT that will have a negative impact on their quality of life and neurocognitive function. The symptoms of brain tumors\\u000a depend

Jerome M. Butler; Stephen R. Rapp; Edward G. Shaw

2006-01-01

262

Radiation therapy in the management of childhood brain tumors  

Microsoft Academic Search

Radiation therapy (RT) still plays a major role in the management of intracranial malignancies, together with surgical resection\\u000a and, more recently, chemotherapy. This is a review of the experience with fractionated external beam RT. In medulloblastomas,\\u000a combined modalities currently achieve a 5-year survival in excess of 70% in low-risk subgroups and 40% in the subgroups considered\\u000a to be high risk.

Jean-Louis Habrand; Renaud De Crevoisier

2001-01-01

263

High contrast, CdTe portal scanner for radiation therapy  

Microsoft Academic Search

A solid state, CdTe, linear array, portal imaging system is presented. One of the most promising new technologies for improving the quality of radiation therapy is the use of real-time systems to produce portal images. In the approach presented, a linear array of 256 CdTe photovoltaic detectors attached to a very compact linear scanner, all of which will be mounted

G. Entine; M. R. Squillante; R. Hahn; L. J. Cirignano; W. McGann; P. J. Biggs

1992-01-01

264

Radical external beam radiation therapy for adenocarcinoma of the rectum  

Microsoft Academic Search

External beam megavoltage radiation therapy was used as primary treatment for 123 patients with rectal adenocarcinoma. Surgery\\u000a was undertaken for some patients who had residual tumor. The overall five-year survival rate was 21 per cent. When patients\\u000a were separated into those who presented with clinically mobile and those with clinically fixed rectal tumor masses, the survival\\u000a rates were 38 per

Bernard J. Cummings; Walter D. Rider; Andrew R. Harwood; Thomas J. Keane; Gillian M. Thomas

1983-01-01

265

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

PubMed Central

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.

Lee, Nancy Y.; Le, Quynh-Thu

2008-01-01

266

CT evaluation of effects of cranial radiation therapy in children  

SciTech Connect

A retrospective evaluation was completed of 49 children who received conventional cranial radiation therapy for primary central nervous system and/or skull-base neoplasia and who had follow-up CT studies. In these children, abnormalities in normal parenchyma away from the tumor itself were surprisingly frequent, with or without chemotherapy. Generalized volume loss or atrophy was the most frequent abnormality (51%), but in this population it may have resulted from a variety of causes. Calcification in nontumorous parenchyma was common (28%) with or without chemotherapy. The most frequent site of calcification was subcortical at the gray-white junction. Calcification was progressive over 1-2 years and correlated pathologically with mineralizing microangiopathy and dystrophic calcification with demyelination. White-matter abnormalities other than those associated with shunt malfunction and tumor edema occurred in 26% of the patients. Both white-matter abnormalities and calcification occurred predominantly in younger children, particularly those under 3 years old at the time of radiation therapy. Of the 21 children who received chemotherapy in this series, only two received methotrexate. White-matter abnormalities and calcifications occurred with similar frequency in children with and without chemotherapy; thus, radiation therapy is the most likely cause of these findings.

Davis, P.C.; Hoffman, J.C. Jr.; Pearl, G.S.; Braun, I.F.

1986-09-01

267

Computed tomography in radiation therapy treatment planning of hepatic metastases  

SciTech Connect

Forty-four patients with symptomatic hepatic metastases from a colon primary had CT prior to radiation therapy treatment planning. A control group of 44 patients with no evidence of liver metastases was analyzed for comparison. The objectives of planning were to deliver as homogeneous a dose to the whole liver as possible and not treat one kidney or more than one-half of both kidneys. Conventional anteroposterior/posteroanterior portals were found to be inadequate for the treatment of 60% of patients with metastases and 10% of patients with no liver involvement. Among the metastatic group, 50% required oblique planning, 40% anteroposterior/posteroanterior and 9% posteroanterior and left lateral portals to meet the treatment planning objectives. Among the control group of patients with no liver metastases, only 9% required oblique portals and 8% could not be treated because of left hydronephrosis or a solitary right kidney. It is concluded that all patients receiving radiation therapy to the liver for symptoms or prophylaxis require CT for optimum radiation therapy treatment planning.

Rostock, R.A.; Fishman, E.K.; Zinreich, E.S.; Lee, D.J.

1985-07-01

268

Adjoint Monte Carlo Methods for Radiation Therapy Treatment Planning  

SciTech Connect

Intensity-modulated radiation therapy is a new technique for administering external beam radiation therapy. This technology modulates the intensity and shape of the treatment beam as a function of source position and patient anatomy. This process of conforming the source to the patient requires the optimization of the independent variables of the source field. In this study, adjoint Monte Carlo methods were used to compute the sensitivity field that corresponds to a prescribed dose distribution. Given these data, linear and nonlinear optimization models were constructed with a simplified geometry to compute an optimized set of beams to deliver a desired dose distribution. It was shown that, for a simple geometric model, adjoint Monte Carlo methods can be used as the basis for inverse radiation therapy treatment planning. By using flux-to-dose conversion factors as adjoint sources, it is possible to develop an influence matrix that provides the sensitivity of the dose at a single point in the patient to all points in the treatment source field. These data may be used to determine an optimized set of treatment beams.

Kowalok, M.; Henderson, D.L.; Mackie, T.R.

2001-06-17

269

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

SciTech Connect

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 isocenter 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).

Lingos, T.I.; Recht, A.; Vicini, F.; Abner, A.; Silver, B.; Harris, J.R. (Joint Center for Radiation Therapy, Harvard Medical School, Boston, MA (USA))

1991-07-01

270

Preoperative therapy for esophageal cancer: a randomized comparison of chemotherapy versus radiation therapy.  

PubMed

Ninety-six patients with operable epidermoid cancer of the esophagus were entered into a phase III, random assignment study designed to compare the efficacy of two preoperative approaches (chemotherapy [CT] or radiation therapy [RT]). Major study end points were objective response rates, surgical outcome, and recurrence pattern. Patients were randomly assigned to receive either two cycles of cisplatin, vindesine, and bleomycin or 55 Gy of radiation before a planned surgical procedure. Postoperative crossover therapy (radiation to those receiving preoperative CT and vice versa) was given to patients with T3Nany or unresectable tumors. Objective response rates of the primary tumor to preoperative therapy were similar (RT 64%, CT 55%), as were operability rates (RT 77%, CT 75%), resection rates (RT 65%, CT 58%), and operative mortality (RT 13.5%, CT 11.1%). Significantly higher doses of CT could be administered when CT was given as initial therapy, rather than after RT/surgery. Local failure or persistence occurred in 33% of operable patients. The median survival for all patients was 11 months; 20% remain alive without disease (median follow-up, 34 months). Because of the crossover design, it was not possible to analyze survival according to the preoperative therapy arm alone. This study suggests that since CT is as effective in treating local tumor as RT, but can also potentially treat systemic disease, investigational programs using CT before surgery as part of initial treatment for localized esophageal cancer should continue. However, if a significant impact on overall survival is to be achieved, more effective chemotherapy regimens or schedules need to be identified. Outside of carefully designed clinical trials, surgery alone or radiation alone remain standard therapy. PMID:1696309

Kelsen, D P; Minsky, B; Smith, M; Beitler, J; Niedzwiecki, D; Chapman, D; Bains, M; Burt, M; Heelan, R; Hilaris, B

1990-08-01

271

Radiation therapy for neovascular age-related macular degeneration  

PubMed Central

Antivascular endothelial growth factor (anti-VEGF) therapies represent the standard of care for most patients presenting with neovascular (wet) age-related macular degeneration (neovascular AMD). Anti-VEGF drugs require repeated injections and impose a considerable burden of care, and not all patients respond. Radiation targets the proliferating cells that cause neovascular AMD, including fibroblastic, inflammatory, and endothelial cells. Two new neovascular AMD radiation treatments are being investigated: epimacular brachytherapy and stereotactic radiosurgery. Epimacular brachytherapy uses beta radiation, delivered to the lesion via a pars plana vitrectomy. Stereotactic radiosurgery uses low voltage X-rays in overlapping beams, directed onto the lesion. Feasibility data for epimacular brachytherapy show a greatly reduced need for anti-VEGF therapy, with a mean vision gain of 8.9 ETDRS letters at 12 months. Pivotal trials are underway (MERLOT, CABERNET). Preliminary stereotactic radiosurgery data suggest a mean vision gain of 8 to 10 ETDRS letters at 12 months. A large randomized sham controlled stereotactic radiosurgery feasibility study is underway (CLH002), with pivotal trials to follow. While it is too early to conclude on the safety and efficacy of epimacular brachytherapy and stereotactic radiosurgery, preliminary results are positive, and these suggest that radiation offers a more durable therapeutic effect than intraocular injections.

Petrarca, Robert; Jackson, Timothy L

2011-01-01

272

Aesthetic results following partial mastectomy and radiation therapy  

SciTech Connect

This study was undertaken to determine the aesthetic changes inherent in partial mastectomy followed by radiation therapy in the treatment of stage I and stage II breast cancer. A retrospective analysis of breast cancer patients treated according to the National Surgical Adjuvant Breast Project Protocol B-06 was undertaken in 57 patients from 1984 to the present. The size of mastectomy varied between 2 x 1 cm and 15 x 8 cm. Objective aesthetic outcome, as determined by physical and photographic examination, was influenced primarily by surgical technique as opposed to the effects of radiation. These technical factors included orientation of resections, breast size relative to size of resection, location of tumor, and extent and orientation of axillary dissection. Regarding cosmesis, 80 percent of patients treated in this study judged their result to be excellent or good, in comparison to 50 percent excellent or good as judged by the plastic surgeon. Only 10 percent would consider mastectomy with reconstruction for contralateral disease. Asymmetry and contour abnormalities are far more common than noted in the radiation therapy literature. Patients satisfaction with lumpectomy and radiation, however, is very high. This satisfaction is not necessarily based on objective criteria defining aesthetic parameters, but is strongly influenced by retainment of the breast as an original body part.

Matory, W.E. Jr.; Wertheimer, M.; Fitzgerald, T.J.; Walton, R.L.; Love, S.; Matory, W.E.

1990-05-01

273

Impact of angiotensin II receptor blocker therapy (olmesartan or valsartan) on coronary atherosclerotic plaque volume measured by intravascular ultrasound in patients with stable angina pectoris.  

PubMed

Coronary plaques can be reduced by some medications. The aim of this study was to compare the effects of 2 angiotensin II receptor blockers (olmesartan at 20 mg/day or valsartan at 80 mg/day) on coronary plaque by coronary intravascular ultrasound. One hundred hypertensive patients with stable angina pectoris who underwent elective percutaneous coronary intervention were randomly selected to receive 1 of the 2 angiotensin II receptor blockers after coronary intervention. Nontarget coronary lesions with mild to moderate stenosis were measured by volumetric intravascular ultrasound at baseline and after 6 months. After 6 months, both the olmesartan and the valsartan groups showed significant reduction of the examined coronary plaque volume (46.2 24.1 mm at baseline vs 41.6 21.1 mm at 6 months: 4.7% decrease, p = 0.0002; and 47.2 32.7 mm at baseline vs 42.5 30.2 mm at 6 months: 4.8% decrease, p = 0.002, respectively). There was no statistically significant difference of plaque regression between the 2 groups (p = 0.96). In conclusion, there was a significant decrease from baseline in the coronary plaque volume in patients with stable angina pectoris who received olmesartan or valsartan for 6 months. In addition, there was no significant difference in the reduction of plaque volume achieved by these 2 medications. PMID:23623047

Ishii, Hideki; Kobayashi, Masakazu; Kurebayashi, Nobutake; Yoshikawa, Daiji; Suzuki, Susumu; Ichimiya, Satoshi; Kanashiro, Masaaki; Sone, Takahito; Tsuboi, Hideyuki; Amano, Tetsuya; Uetani, Tadayuki; Harada, Ken; Marui, Nobuyuki; Murohara, Toyoaki

2013-04-24

274

American Society of Radiation Oncology Recommendations for Documenting Intensity-Modulated Radiation Therapy Treatments  

Microsoft Academic Search

Despite the widespread use of intensity-modulated radiation therapy (IMRT) for approximately a decade, a lack of adequate guidelines for documenting these treatments persists. Proper IMRT treatment documentation is necessary for accurate reconstruction of prior treatments when a patient presents with a marginal recurrence. This is especially crucial when the follow-up care is managed at a second treatment facility not involved

Timothy Holmes; Rupak Das; Daniel Low; Fang-Fang Yin; James Balter; Jatinder Palta; Patricia Eifel

2009-01-01

275

Effects of radiation therapy and chemotherapy on testicular function  

SciTech Connect

Chemotherapy and radiation therapy are commonly used alone or in combination in the curative management of many malignancies in adolescent and adult males. Over the last 15-20 years, the striking success in the treatment of some common cancers in reproductive males has led to increasing concern for damage to normal tissues, such as the testes, resulting from curative cancer treatment. Indeed, a major future goal for cancer treatment will be to improve on the complication-free cure rate. Inherent in achieving this goal is to understand the pathophysiology and clinical expression of testicular injury. Both chemotherapy and radiation therapy result in germ cell depletion with the development of oligo- to azoospermia and testicular atrophy. The type of drug (particularly the alkylating agents), duration of treatment, intensity of treatment, and drug combination are major variables in determining the extent and duration of testicular injury. Testicular injury with chemotherapy also appears to vary with the age of the patient at the time of treatment. Newer drug combinations are now being used which appear to have curative potential in tumors such as Hodgkin's disease and germ cell testicular cancer with less potential for testicular injury. The most accurate and complete information on radiation injury to the testes is derived from two studies of normal volunteers who received graded single doses directly to the testes. A clear dose-response relationship of clinical and histological testicular damage was found with gradual recovery occurring following doses of up to 600 cGy. While these two studies provide an important clinical data base, radiation therapy used in treating cancers involves multiple daily treatments, usually 25-35 delivered over several weeks. Additionally, direct testicular irradiation is seldom used clinically. 37 references.

Kinsella, T.J. (Univ. of Wisconsin Clinical Cancer Center, Madison (USA))

1989-01-01

276

Melanoma Therapy via Peptide-Targeted a-Radiation  

SciTech Connect

Malignant melanoma is the most lethal form of skin cancer. Current chemotherapy and external beam radiation therapy regimens are ineffective agents against melanoma, as shown by a 10-year survival rate for patients with disseminated disease of approximately 5% (reference?). In this study, the unique combination of a melanoma targeting peptide and an in vivo generated a-particle emitting radioisotope was investigated for its melanoma therapy potential. Alpha-radiation is densely ionizing and energy is locally absorbed, resulting in high concentrations of destructive free radicals and irreparable DNA double strand breaks. This high linear-energy-transfer overcomes radiation resistant tumor cells and oxygen-enhancement effects. The melanoma targeting peptide DOTA-Re(Arg11)CCMSH was radiolabeled with 212Pb, the parent of 212Bi, which decays via alpha and beta decay. Biodistribution and therapy studies were performed in the B16/F1 melanoma bearing C57 mouse flank tumor model. 212Pb[DOTA]-R e(Arg11)CCMSH exhibited rapid tumor uptake and extended retention coupled with rapid whole body disappearance. Radiation dose delivered to the tumor was estimated to be 61 cGy/uCi 212Pb administered. Treatment of melanoma-bearing mice with 50, 100 and 200 uCi of 212Pb[DOTA]-Re(Arg11)CCMSH extended mean survival of mice to 22, 28, and 49.8 days, respectively, compared to the 14.6 day mean survival of the placebo control group. Forty-five percent of the mice receiving 200 uCi survived the study disease-free.

Miao, Yubin; Hylarides, Mark; Fisher, Darrell R.; Shelton, Tiffani; Moore, Herbert A.; Wester, Dennis W.; Fritzberg, Alan R.; Winkelmann, Christopher T.; Hoffman, Timothy J.; Quinn, Thomas P.

2005-08-01

277

Future of radiation therapy for malignant melanoma in an era of newer, more effective biological agents  

PubMed Central

The incidence of melanoma is rising. The primary initial treatment for melanoma continues to be wide local excision of the primary tumor and affected lymph nodes. Exceptions to wide local excision include cases where surgical excision may be cosmetically disfiguring or associated with increased morbidity and mortality. The role of definitive or adjuvant radiotherapy has largely been relegated to palliative measures because melanoma has been viewed as a prototypical radiotherapy-resistant cancer. However, the emerging clinical and radiobiological data summarized here suggests that many types of effective radiation therapy, such as radiosurgery for melanoma brain metastases, plaque brachytherapy for uveal melanoma, intensity modulated radiotherapy for melanoma of the head and neck, and adjuvant radiotherapy for selected high-risk, node-positive patients can improve outcomes. Similarly, although certain chemotherapeutic agents and biologics have shown limited responses, long-term control for unresectable tumors or disseminated metastatic disease has been rather disappointing. Recently, several powerful new biologics and treatment combinations have yielded new hope for this patient group. The recent identification of several clinically linked melanoma gene mutations involved in mitogen-activated protein kinase (MAPK) pathway such as BRAF, NRAS, and cKIT has breathed new life into the drive to develop more effective therapies. Some of these new therapeutic approaches relate to DNA damage repair inhibitors, cellular immune system activation, and pharmacological cell cycle checkpoint manipulation. Others relate to the investigation of more effective targeting and dosing schedules for underutilized therapeutics, such as radiotherapy. This paper summarizes some of these new findings and attempts to give some context to the renaissance in melanoma therapeutics and the potential role for multimodality regimens, which include certain types of radiotherapy as aids to locoregional control in sensitive tissues.

Khan, Mohammad K; Khan, Niloufer; Almasan, Alex; Macklis, Roger

2011-01-01

278

Monte Carlo modeling of radiation dose distributions in intravascular radiation therapy.  

PubMed

Radiation dose distributions are developed for balloon and wire sources of radioactivity within coronary arteries. The Monte Carlo codes MCNP 4B and EGS4 were used to calculate dose distributions for photons and electrons at discrete energies around such sources, with and without the presence of a high-density atherosclerotic plaque. An interactive computer program was developed which then calculates dose distributions for many radionuclides by applying the emission spectra to the discrete energy grids calculated by the Monte Carlo codes, weighting appropriately for electron energy and abundance. Results for Re-186 and Re-188 balloon sources are shown in comparison to an Ir-192 wire source. The program provides dose distributions as well as estimates of activity levels needed to deliver prescribed doses to the vessel wall at selected distances from the lumen in a selected time interval. In addition, dose calculations are presented in this paper for other organs in the body, from photon radiation as well as from possible loss of liquid activity into the bloodstream in the case of a balloon rupture. These results, especially the interactive computer program permitting easy comparison of various radionuclides and their physical characteristics, will greatly facilitate the comparison process and aid in the selection of the best candidate(s) for clinical use. PMID:10841413

Stabin, M G; Konijnenberg, M; Knapp, F F; Spencer, R H

2000-05-01

279

Late effects of radiation therapy on the gastrointestinal tract  

SciTech Connect

Late gastrointestinal complications of radiation therapy have been recognized but not extensively studied. In this paper, the late effects of radiation on three gastrointestinal sites, the esophagus, the stomach, and the bowel, are described. Esophageal dysmotility and benign stricture following esophageal irradiation are predominantly a result of damage to the esophageal wall, although mucosal ulcerations also may persist following high-dose radiation. The major late morbidity following gastric irradiation is gastric ulceration caused by mucosal destruction. Late radiation injury to the bowel, which may result in bleeding, frequency, fistula formation, and, particularly in small bowel, obstruction, is caused by damage to the entire thickness of the bowel wall, and predisposing factors have been identified. For each site a description of the pathogenesis, clinical findings, and present management is offered. Simple and reproducible endpoint scales for late toxicity measurement were developed and are presented for each of the three gastrointestinal organs. Factors important in analyzing late complications and future considerations in evaluation and management of radiation-related gastrointestinal injury are discussed.

Coia, L.R. [Fox Chase Cancer Center, Philadelphia, PA (United States); Myerson, R.J. [Washington Univ. Medical Center, St. Louis, MO (United States); Tepper, J.E. [North Carolina School of Medicine, Chapel Hill, NC (United States)

1995-03-30

280

Intraoperative radiation therapy (IORT) for previously untreated malignant gliomas  

PubMed Central

Background Intraoperative radiation therapy (IORT) is one of the methods used to deliver a large single dose to the tumor tissue while reducing the exposure of normal surrounding tissue. However, the usefulness of intraoperative electron therapy for malignant gliomas has not been established. Methods During the period from 1987 to 1997, 32 patients with malignant gliomas were treated with IORT. The histological diagnoses were anaplastic astrocytoma in 11 patients and glioblastoma in 21 patients. Therapy consisted of surgical resection and intraoperative electron therapy using a dose of 1215 Gy (median, 15 Gy). The patients later underwent postoperative external radiation therapy (EXRT) with a median total dose of 60 Gy. Each of the 32 patients treated with IORT was randomly matched with patients who had been treated with postoperative EXRT alone (control). Patients were matched according to histological grade, age, extent of tumor removal, and tumor location. Results In the anaplastic astrocytoma group, the one-, two- and five-year survival rates were 81%, 51% and 15%, respectively in the IORT patients and 54%, 43% and 21%, respectively in the control patients. In the glioblastoma group, one-, two- and five-year survival rates were 63%, 26% and 0%, respectively in the IORT patients and 70%, 18% and 6%, respectively in the control patients. There was no significant difference between survival rates in the IORT patients and control patients in either the anaplastic astrocytoma group or glioblastoma group. Conclusions IORT dose not improve survival of patients with malignant gliomas compared to that of patients who have received EXRT alone.

Nemoto, Kenji; Ogawa, Yoshihiro; Matsushita, Haruo; Takeda, Ken; Takai, Yoshihiro; Yamada, Shogo; Kumabe, Toshihiro

2002-01-01

281

Accuracy of Marketing Claims by Providers of Stereotactic Radiation Therapy  

PubMed Central

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.

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

2013-01-01

282

The Role of a Prone Setup in Breast Radiation Therapy  

PubMed Central

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.

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

2011-01-01

283

Combined ultrasound and radiation therapy treatment of human superficial tumors  

SciTech Connect

Ultrasound, used to generate local tumor hyperthermia, was combined with radiation therapy in a pilot study to determine efficacy and toxicity of this combined-modality therapy. Twenty-one lesions in eighteen patients were treated at graded doses from 24000-4000 rads (24-40 Gy) with ultrasonic hyperthermia administered immediately prior to irradiation at 43.5/sup 0/C +/- 0.5/sup 0/C for one hour. The overall response rate was 100%, with a 62% complete response rate. The response rate for control unheated lesions in the same patient in the same radiation field was markedly lower. Heat treatment alone in the same patients also showed lower response rates (50% overall and 10% complete) with a short response duration. Toxicities were minimal, consisting of one case with long-term treatment-associated sequelae. It is concluded that this combined modality of therapy is safe and effective where applied in human superficial tumors and that further development is warranted.

Corry, P.M.; Spanos, W.J.; Tilchen, E.J.; Barlogie, B.; Barkley, H.T.; Armour, E.P.

1982-10-01

284

Combining molecular targeted agents with radiation therapy for malignant gliomas  

PubMed Central

The expansion in understanding the molecular biology that characterizes cancer cells has led to the rapid development of new agents to target important molecular pathways associated with aberrant activation or suppression of cellular signal transduction pathways involved in gliomagenesis, including epidermal growth factor receptor, vascular endothelial growth factor receptor, mammalian target of rapamycin, and integrins signaling pathways. The use of antiangiogenic agent bevacizumab, epidermal growth factor receptor tyrosine kinase inhibitors gefitinib and erlotinib, mammalian target of rapamycin inhibitors temsirolimus and everolimus, and integrin inhibitor cilengitide, in combination with radiation therapy, has been supported by encouraging preclinical data, resulting in a rapid translation into clinical trials. Currently, the majority of published clinical studies on the use of these agents in combination with radiation and cytotoxic therapies have shown only modest survival benefits at best. Tumor heterogeneity and genetic instability may, at least in part, explain the poor results observed with a single-target approach. Much remains to be learned regarding the optimal combination of targeted agents with conventional chemoradiation, including the use of multipathways-targeted therapies, the selection of patients who may benefit from combined treatments based on molecular biomarkers, and the verification of effective blockade of signaling pathways.

Scaringi, Claudia; Enrici, Riccardo Maurizi; Minniti, Giuseppe

2013-01-01

285

Changes in T-cell subsets after radiation therapy  

SciTech Connect

The T-cell subsets of 129 patients with cancer were counted before and after radiation therapy. The cells were labeled with monoclonal antibodies that were specific for each type of T cell. Significant changes after therapy were decreases in the proportion of T-helper/inducer cells, pan-T cells, and in the ratio of T-helper/inducer to T-suppressor/cytotoxic cells. There was an increase in the percentage of T-suppressor/cytotoxic cells. When the site of the primary cancer was considered, genitourinary cancer and cancer of the head and neck both showed a decreased percentage of T-helper/inducer cells and a reduced ratio of T-helper/inducer to T-suppressor/cytotoxic cells. The percentage of pan-T cells in head and neck cancer and the ratio of T-helper/inducer to T-suppressor/cytotoxic cells in breast cancer were decreased. The percentage of T-helper cells was particularly decreased by radiation therapy in advanced stages of cancer, in higher grade tumors, and in larger tumors. The absolute numbers of various T-cell subsets were decreased in all groups.

Yang, S.J.; Rafla, S.; Youssef, E.; Selim, H.; Salloum, N.; Chuang, J.Y.

1988-08-01

286

Management of arterial occlusive disease following radiation therapy.  

PubMed

Clinically significant arterial occlusive disease developed in 26 patients at between 5 months and 44 years (mean(s.d.) 10.7(12.0) years) following radiation therapy. Therapeutic radiation was associated with lesions of the carotid artery (nine patients), subclavian-axillary arteries (seven) and the abdominal aorta and its branches (10). Clinical presentations included transient ischemic attack, stroke, vertebrobasilar insufficiency, carotid bruit, upper- or lower-extremity ischemia and renovascular hypertension. Surgery for cerebrovascular insufficiency included carotid endarterectomy with vein patch, interposition grafting or subclavian-to-carotid bypass. Carotid or subclavian-to-axillary bypass was performed for upper-extremity ischemia. A combination of endarterectomy and Dacron or saphenous vein grafts was used for infrarenal reconstruction. Tunnels were placed orthotopically. Musculocutaneous flaps assisted in healing selected wounds. Ureteral catheters were useful adjuncts in abdominal vascular reconstructions. There were no operative deaths, strokes or amputations. One patient had recurrent transient ischemic attacks following subclavian-to-carotid bypass. The mean(s.d.) postoperative follow-up was 48.1(39.6) months. Patients presenting with end-organ ischemia following radiation therapy can be managed successfully with aggressive surgical revascularization using a broad spectrum of reconstructive techniques. PMID:8861426

Andros, G; Schneider, P A; Harris, R W; Dulawa, L B; Oblath, R W; Salles-Cunha, S X

1996-04-01

287

Approaches to 4-D intensity modulated radiation therapy planning with fraction constraints  

Microsoft Academic Search

Cancer is the second leading cause of death in the US preceded by cardiac disease. Almost all cancer patients depend on radiation therapy sometime throughout their treatment. Intensity modulated radiation therapy is a state-of-the-art method of delivering radiation that maximizes radiation exposure of the tumor and avoids excessive coverage of the surrounding healthy structures of the body. When image-guided radiation

Delal Dink

2005-01-01

288

Family history of prostate cancer and relapse after definitive external beam radiation therapy  

Microsoft Academic Search

PurposeThe influence of family history on outcome after definitive therapy for prostate cancer has been disputed. One series reported increased relapse rates in men with a positive family history of prostate cancer treated with radical prostatectomy or radiation therapy, whereas others have reported no difference in outcome. We examined our series of patients treated with definitive external beam radiation therapy

Michael E Ray; Rodney L Dunn; Kathleen A Cooney; Howard M Sandler

2003-01-01

289

Adjuvant external beam radiation therapy with concurrent chemotherapy in the management of gallbladder carcinoma  

Microsoft Academic Search

Purpose: This study was performed to evaluate the outcome of patients with gallbladder cancer who received postoperative concurrent chemotherapy and radiation therapy.Methods and Materials: Curative resection followed by adjuvant combined modality therapy with external beam radiation therapy (EBRT) and chemotherapy was attempted in 21 consecutive gallbladder carcinoma (GBC) patients at the Mayo Clinic from 1985 through 1997. All patients received

John J Kresl; Steven E Schild; George T Henning; Leonard L Gunderson; John Donohue; Henry Pitot; Michael G Haddock; David Nagorney

2002-01-01

290

Stereotactic Body Radiation Therapy (SBRT) in Pancreatic Cancer: Is It Ready for Prime Time?  

Microsoft Academic Search

Summary Pancreatic cancer is a devastating disease with few effective treatment modalities. Stereotactic body radiation therapy is a novel technique that takes advantage of the technologic advancements in image guidance and radiation dose delivery to direct ablative doses to tumors with acceptable toxicity that was not previously achievable with conventional techniques. Recent literature contains reports of stereotactic body radiation therapy

Bryan W Chang; Muhammad W Saif

2008-01-01

291

Intensity-modulated radiation therapy for pediatric medulloblastoma: early report on the reduction of ototoxicity  

Microsoft Academic Search

Purpose: The combination of cisplatin chemotherapy and radiation therapy for the treatment of medulloblastoma has been shown to cause significant ototoxicity, impairing a childs cognitive function and quality of life. Our purpose is to determine whether the new conformal technique of intensity-modulated radiation therapy (IMRT) can achieve lower rates of hearing loss by decreasing the radiation dose delivered to the

Eugene Huang; Bin S Teh; Douglas R Strother; Quillin G Davis; J. Kam Chiu; Hsin H Lu; L. Steven Carpenter; Wei-Yuan Mai; Murali M Chintagumpala; Michael South; Walter H Grant III; E. Brian Butler; Shiao Y Woo

2002-01-01

292

The Treatment Responses in Cases of Radiation Therapy to Portal Vein Thrombosis in Advanced Hepatocellular Carcinoma  

Microsoft Academic Search

Purpose: To review the response to radiation therapy for hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT) and determine the factors favoring its efficacy. Methods and Materials: Patients with HCC and PVT referred for radiation therapy between 1997 and 2005 were retrospectively reviewed. Patients who had undergone treatment to primary HCC before radiation or had extrahepatic metastasis were excluded. A

Yu-Jie Huang; Hsuan-Chih Hsu; Chang-Yu Wang; Chong-Jong Wang; Hui-Chun Chen; Eng-Yen Huang; Fu-Min Fang; Sheng-Nan Lu

2009-01-01

293

Calculation of the dose to lymphocytes in external beam radiation therapy  

Microsoft Academic Search

Lymphopenia is known to occur in patients undergoing external beam radiation therapy when the radiation fields encompass major blood vessels and lymphatic tissue. The dose received by the lymphocytes has up to now not been determined. We present here a general formalism for the calculation of the lymphocyte dose for a patient undergoing fractionated radiation therapy at any irradiation site.

K. E. Ekstrand; R. L. Dixon; S. Plunkett; M. Raben

1981-01-01

294

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

Microsoft Academic Search

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

J. B. Epstein; P. Stevenson-Moore

1986-01-01

295

A Method for Evaluating Quality Assurance Needs in Radiation Therapy  

SciTech Connect

The increasing complexity of modern radiation therapy planning and delivery techniques challenges traditional prescriptive quality control and quality assurance programs that ensure safety and reliability of treatment planning and delivery systems under all clinical scenarios. Until now quality management (QM) guidelines published by concerned organizations (e.g., American Association of Physicists in Medicine [AAPM], European Society for Therapeutic Radiology and Oncology [ESTRO], International Atomic Energy Agency [IAEA]) have focused on monitoring functional performance of radiotherapy equipment by measurable parameters, with tolerances set at strict but achievable values. In the modern environment, however, the number and sophistication of possible tests and measurements have increased dramatically. There is a need to prioritize QM activities in a way that will strike a balance between being reasonably achievable and optimally beneficial to patients. A systematic understanding of possible errors over the course of a radiation therapy treatment and the potential clinical impact of each is needed to direct limited resources in such a way to produce maximal benefit to the quality of patient care. Task Group 100 of the AAPM has taken a broad view of these issues and is developing a framework for designing QM activities, and hence allocating resources, based on estimates of clinical outcome, risk assessment, and failure modes. The report will provide guidelines on risk assessment approaches with emphasis on failure mode and effect analysis (FMEA) and an achievable QM program based on risk analysis. Examples of FMEA to intensity-modulated radiation therapy and high-dose-rate brachytherapy are presented. Recommendations on how to apply this new approach to individual clinics and further research and development will also be discussed.

Huq, M. Saiful [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA (United States)], E-mail: huqs@upmc.edu; Fraass, Benedick A. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, MI (United States); Dunscombe, Peter B. [Department of Medical Physics, Tom Baker Cancer Center, Calgary, AB (Canada); Gibbons, John P. [Department of Medical Physics, Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Ibbott, Geoffrey S. [Radiological Physics Center, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Medin, Paul M. [Department of Radiation Oncology, Nebraska Medical Center, Omaha, NE (United States); Mundt, Arno [Department of Radiation Oncology, University of California-San Diego, San Diego, CA (United States); Mutic, Sassa [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Palta, Jatinder R. [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Thomadsen, Bruce R. [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Williamson, Jeffrey F. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Yorke, Ellen D. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2008-05-01

296

Arc binary intensity modulated radiation therapy (AB IMRT)  

NASA Astrophysics Data System (ADS)

The state of the art Intensity Modulate Radiation Therapy (IMRT) has been one of the most significant breakthroughs in the cancer treatment in the past 30 years. There are two types of IMRT systems. The first system is the binary-based tomotherapy, represented by the Peacock (Nomos Corp) and Tomo unit (TomoTherapy Inc.), adopting specific binary collimator leafs to deliver intensity modulated radiation fields in a serial or helical fashion. The other uses the conventional dynamic multileaf collimator (MLC) to deliver intensity modulated fields through a number of gantry positions. The proposed Arc Binary IMRT attempts to deliver Tomo-like IMRT with conventional dynamic MLC and combines the advantages of the two types of IMRT techniques: (1) maximizing the number of pencil beams for better dose optimization, (2) enabling conventional linear accelerator with dynamic MLC to deliver Tomo-like IMRT. In order to deliver IMRT with conventional dynamic MLC in a binary fashion, the slice-by-slice treatment with limited slice thickness has been proposed in the thesis to accommodate the limited MLC traveling speed. Instead of moving the patient to subsequent treatment slices, the proposed method offsets MLC to carry out the whole treatment, slice by slice sequentially, thus avoid patient position error. By denoting one arc pencil beam set as a gene, genetic algorithm (GA) is used as the searching engine for the dose optimization process. The selection of GA parameters is a crucial step and has been studied in depth so that the optimization process will converge with reasonable speed. Several hypothetical and clinical cases have been tested with the proposed IMRT method. The comparison of the dose distribution with other commercially available IMRT systems demonstrates the clear advantage of the new method. The proposed Arc Binary Intensity Modulated Radiation Therapy is not only theoretically sound but practically feasible. The implementation of this method would expand the capacity of the conventional linear accelerators in delivering high quality IMRT.

Yang, Jun

297

Radiation hardness of the storage phosphor europium doped potassium chloride for radiation therapy dosimetry  

PubMed Central

Purpose: An important property of a reusable dosimeter is its radiation hardness, that is, its ability to retain its dosimetric merits after irradiation. The radiation hardness of europium doped potassium chloride (KCl:Eu2+), a storage phosphor material recently proposed for radiation therapy dosimetry, is examined in this study. Methods: Pellet-style KCl:Eu2+ dosimeters, 6 mm in diameter, and 1 mm thick, were fabricated in-house for this study. The pellets were exposed by a 6 MV photon beam or in a high dose rate 137Cs irradiator. Macroscopic properties, such as radiation sensitivity, dose response linearity, and signal stability, were studied with a laboratory photostimulated luminescence (PSL) readout system. Since phosphor performance is related to the state of the storage centers and the activator, Eu2+, in the host lattice, spectroscopic and temporal measurements were carried out in order to explore radiation-induced changes at the microscopic level. Results: KCl:Eu2+ dosimeters retained approximately 90% of their initial signal strength after a 5000 Gy dose history. Dose response was initially supralinear over the dose range of 100700 cGy but became linear after 60 Gy. Linearity did not change significantly in the 05000 Gy dose history spanned in this study. Annealing high dose history chips resulted in a return of supralinearity and a recovery of sensitivity. There were no significant changes in the PSL stimulation spectra, PSL emission spectra, photoluminescence spectra, or luminescence lifetime, indicating that the PSL signal process remains intact after irradiation but at a reduced efficiency due to reparable radiation-induced perturbations in the crystal lattice. Conclusions: Systematic studies of KCl:Eu2+ material are important for understanding how the material can be optimized for radiation therapy dosimetry purposes. The data presented here indicate that KCl:Eu2+ exhibits strong radiation hardness and lends support for further investigations of this novel material.

Driewer, Joseph P.; Chen, Haijian; Osvet, Andres; Low, Daniel A.; Li, H. Harold

2011-01-01

298

The New Radiation Therapy Clinical Practice: The Emerging Role of Clinical Peer Review for Radiation Therapists and Medical Dosimetrists  

SciTech Connect

The concept of peer review for radiation therapists and medical dosimetrists has been studied very little in radiation oncology practice. The purpose of this manuscript is to analyze the concept of peer review in the clinical setting for both radiation therapists and medical dosimetrists. The literature reviewed both the percentages and causes of radiation therapy deviations. The results indicate that peer review can be both implemented and evaluated into both the radiation therapist and medical dosimetrist clinical practice patterns.

Adams, Robert D.; Marks, Lawrence B. [UNC Department of Radiation Oncology, Chapel Hill, NC (United States); Pawlicki, Todd [Department of Radiation Oncology, University of California, San Diego, CA (United States); Hayman, James [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Church, Jessica, E-mail: jachurch@email.unc.ed [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

2010-01-01

299

[Radiation-induced and therapy-related AML/MDS].  

PubMed

Radiation induced acute myeloid leukemia (AML) was recognized a century ago, soon after mankind found radiation. Atomic bomb survivors developed de novo AML with relatively short latency with very high frequency. By contrast, excess occurrence of myelodysplastic syndrome (MDS) as well as solid tumors was found decades late. This difference may be due to etiology that many de novo AML patients harbor chimeric leukemogenic genes caused by chromosomal translocations, while MDS patients rarely carry chimeras. In addition, epigenetic change would play important roles. Therapy related leukemia is mainly caused by topoisomerase II inhibitors that cause de novo AML with an 11q23 translocation or by alkyrating agents that induce MDS/AML with an AML1 point mutation and monosomy 7. PMID:19860183

Inaba, Toshiya

2009-10-01

300

Stereotactic Body Radiation Therapy (SBRT) for adrenal metastases  

Microsoft Academic Search

\\u000a \\u000a Purpose:\\u000a To compare advanced treatment techniques with photons and protons as a stereotactic body radiation therapy (SBRT) for adrenal\\u000a glands metastases.\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a Materials and Methods:\\u000a Planning computer tomographic (CT) scans of 10 patients were selected. A total dose of 45 Gy in 7.5 Gy fractions was prescribed.\\u000a Organs at risk (OAR) were liver and kidneys. Dosevolume metrics were defined to quantify

Marta Scorsetti; Pietro Mancosu; Piera Navarria; Angelo Tozzi; Simona Castiglioni; Elena Clerici; Giacomo Reggiori; Francesca Lobefalo; Antonella Fogliata; Luca Cozzi

2011-01-01

301

Linear algebraic methods applied to intensity modulated radiation therapy  

NASA Astrophysics Data System (ADS)

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.

Crooks, Steven M.; Xing, Lei

2001-10-01

302

Radiation Therapy for Early Stages of Morbus Ledderhose  

Microsoft Academic Search

\\u000a \\u000a Purpose:\\u000a To evaluate the efficacy of radiation therapy (RT) in the treatment of early stages of benign plantar fibromatosis (Morbus\\u000a Ledderhose [ML]).\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a Patients and Methods:\\u000a From 2003 to 2008, 24 patients (33 sites) with a mean age of 52 years received RT for symptomatic ML. Prior to RT, 19 patients\\u000a complained of pain and 15 had walking difficulties. 21 patients

Reinhard Heyd; Anne Pia Dorn; Markus Herkstrter; Claus Rdel; Marcus Mller-Schimpfle; Ingeborg Fraunholz

2010-01-01

303

Radiation therapy induces the DNA damage response in peripheral blood  

PubMed Central

Stereotactic body radiation therapy (SBRT) is a radiotherapy modality that delivers highly conformal, ablative doses to a well-defined target. Here, using a semiquantitative multiplexed assay to analyze ATM and H2AX phosphorylation, we show that ATM kinase activity in peripheral blood mononuclear cells is induced following SBRT. This observation of a systemic ATM kinase-dependent DNA damage response in the peripheral blood is unprecedented and promotes the use of ATM serine-1981 phosphorylation as a predictive biomarker for DNA damaging modalities and ATM inhibitors.

Bakkenist, Christopher J.; Czambel, R. Kenneth; Clump, David A.; Greenberger, Joel S.; Beumer, Jan H.; Schmitz, John C.

2013-01-01

304

Current External Beam Radiation Therapy Quality Assurance Guidance: Does It Meet the Challenges of Emerging Image-Guided Technologies?  

Microsoft Academic Search

The traditional prescriptive quality assurance (QA) programs that attempt to ensure the safety and reliability of traditional external beam radiation therapy are limited in their applicability to such advanced radiation therapy techniques as three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, inverse treatment planning, stereotactic radiosurgery\\/radiotherapy, and image-guided radiation therapy. The conventional QA paradigm, illustrated by the American Association of Physicists

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

2008-01-01

305

Internal dosimetry for radiation therapy in coronary arteries.  

PubMed

Acute myocardial infarction, which occurs because of the occlusion of one or more coronary arteries, is the most common form of cardiovascular disease. Balloon angioplasty is often used to treat coronary artery occlusion and is less invasive than surgery involving revascularisation of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of re-stenosis after balloon angioplasty is high (approximately 30-50% within the first year after treatment). Intravascular radiation therapy has been used with several types of radiation source, and researchers have observed some success in decreasing the rate of re-stenosis. In this paper theoretical radiation dose distributions for monoenergetic electrons (with discrete energies) and photons are calculated for blood vessels of diameter 1.5, 3.0 and 4.5 mm with balloon and wire sources using the radiation transport code MCNP4B. Stent sources employing 32P are also simulated. Advantages and disadvantages of the radionuclides and source geometries are discussed, as well as issues regarding possible benefits to the patients. PMID:12382782

Compos, L; Stabin, M

2002-01-01

306

Monte Carlo dose enhancement studies in microbeam radiation therapy  

SciTech Connect

Purpose: A radical radiation therapy treatment for gliomas requires extremely high absorbed doses resulting in subsequent deleterious side effects in healthy tissue. Microbeam radiation therapy (MRT) is an innovative technique based on the fact that normal tissue can withstand high radiation doses in small volumes without any significant damage. The synchrotron-generated x-ray beam is collimated and delivered to an array of narrow micrometer-sized planar rectangular fields. Several preclinical experiments performed at the Brookhaven National Laboratory (BNL) and at the European Synchrotron Radiation Facility (ESRF) confirmed that MRT yields a higher therapeutic index than nonsegmented beams of the same characteristics. This index can be greatly improved by loading the tumor with high atomic number (Z) contrast agents. The aim of this work is to find the high-Z element that provides optimum dose enhancement. Methods: Monte Carlo simulations (PENELOPE/penEasy) were performed to assess the peak and valley doses as well as their ratio (PVDR) in healthy tissue and in the tumor, loaded with different contrast agents. The optimization criteria used were maximization of the ratio between the PVDR values in healthy tissue respect to the PVDR in the tumor and minimization of bone and brain valley doses. Results: Dose enhancement factors, PVDR, and valley doses were calculated for different high-Z elements. A significant decrease of PVDR values in the tumor, accompanied by a gain in the valley doses, was found in the presence of high-Z elements. This enables the deposited dose in the healthy tissue to be reduced. The optimum high-Z element depends on the irradiation configuration. As a general trend, the best outcome is provided by the highest Z contrast agents considered, i.e., gold and thallium. However, lanthanides (especially Lu) and hafnium also offer a satisfactory performance. Conclusions: The remarkable therapeutic index in microbeam radiation therapy can be further improved by loading the tumor with a high-Z element. This study reports quantitative data on several dosimetric magnitudes in order to find the optimum contrast agent. Although the final choice of the element will also depend on possible cytotoxicity, three elements were found to be worthy of mention: gold, thallium, and lutetium.

Martinez-Rovira, I.; Prezado, Y. [ID17 Biomedical Beamline, European Synchrotron Radiation Facility (ESRF), B.P. 220, 6 rue Jules Horowitz, F-38043 Grenoble Cedex, France and Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, E-08028 Barcelona (Spain); ID17 Biomedical Beamline, European Synchrotron Radiation Facility (ESRF), B.P. 220, 6 rue Jules Horowitz, F-38043 Grenoble Cedex (France)

2011-07-15

307

Results of a Radiation Therapist Opinion Survey Identifying, Measuring and Addressing Radiation Therapy Patient Supportive Care Needs  

Microsoft Academic Search

Background: At Sunnybrook's Odette Cancer Centre, a multidisciplinary research team with expertise in radiation therapy and supportive care embarked on a comprehensive, evidence-based three-phase study, Identifying, Measuring and Addressing Radiation Therapy Patient Supportive Care Needs at the Odette Cancer Centre. The subject of this paper, a radiation therapist opinion survey, constitutes Phase I of that study.Purpose: The goal of Phase

John Maamoun; Margaret Fitch; Ruth Barker; Sheila Robson; Carol Gillies; Angela Turner; Irene Lange-Mechlen; Sandra Gardner; Alex Kiss

2009-01-01

308

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

SciTech Connect

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 months after completion of treatment. The relevant electrocardiograms (ECGs) are presented.

Muller-Runkel, R.; Orsolini, G.; Kalokhe, U.P. (Saint Margaret Hospital and Health Centers, Hammond, IN (USA))

1990-11-01

309

ASSESSMENT OF THE RISK FOR DEVELOPING A SECOND MALIGNANCY FROM SCATTERED AND SECONDARY RADIATION IN RADIATION THERAPY  

PubMed Central

With the average age of radiation therapy patients decreasing and the advent of more complex treatment options comes the concern that the incidences of radiation-induced cancer might increase in the future. The carcinogenic effects of radiation are not well understood for the entire dose range experienced in radiation therapy. Longer epidemiological studies are needed to improve current risk models and reduce uncertainties of current risk model parameters. On the other hand, risk estimations are needed today to judge the risks vs. benefits of modern radiation therapy techniques. This paper describes the current state-of-the-art in risk modeling for radiation-induced malignancies in radiation therapy, distinguishing between two volumes. First, the organs within the main radiation field receiving low or intermediate doses (typically between 0.1 and 50 Gy). Second, the organs far away from the treatment volume receiving low doses mainly due to scattered and secondary radiation (typically below 0.1 Gy). The dosimetry as well as the risk model formalisms are outlined. Furthermore, example calculations and results are presented for intensity-modulated photon therapy vs. proton therapy.

Paganetti, Harald

2012-01-01

310

Focused radiation hepatitis after Bragg-peak proton therapy for hepatocellular carcinoma: CT findings  

SciTech Connect

Radiation hepatitis is clearly demonstrated by noncontrast and contrast enhanced CT following radiotherapy for liver diseases. Radiation hepatitis is dependent on dose distribution and is usually demonstrated as nonsegmental bandlike lesion after photon therapy. We report a case of focused, oval-shaped radiation hepatitis that was induced by photon therapy. The attenuation difference was localized in a high-dose area caused by Bragg-peak proton therapy. 17 refs., 2 figs.

Okumura, Toshiyuki; Itai, Yuji; Tsuji, Hiroshi [Central Hospital of Ibaraki (Japan)] [and others

1994-09-01

311

State-of-the-Art External Beam Radiation Therapy: Challenges and Opportunities  

Microsoft Academic Search

Intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT) allow delivery of highly conformal non-convex dose distributions. However, these treatment modalities require precise knowledge of multimodality imaging, internal organ motion, tumor control probabilities, normal tissue complication probabilities, three-dimensional dose calculation and optimization, dynamic beam delivery of non-uniform beam intensities, and most importantly the knowledge of uncertainties in the radiation therapy

Jatinder Palta

2008-01-01

312

New Radiation Therapy Systems: Applications to Human Cancer Treatment and Novel Drug Discovery.  

National Technical Information Service (NTIS)

A significant portion of prostate cancer patients fails standard hormonal therapy and will result in developing locally advanced or metastatic disease. Neither surgery nor radiation therapy (RT) achieves long-term remission for many patients. New therapeu...

G. Pizzomo

2010-01-01

313

Effect of endobronchial radiation therapy on malignant bronchial obstruction  

SciTech Connect

We evaluated the effect of endobronchial radiation therapy in 52 patients with malignant airway occlusion. Fifty-five endobronchial applications of the radioisotope iridium 192 were carried out. Response was assessed by change in performance status, symptom resolution, duration of symptom relief, roentgenographic reaeration, pulmonary function tests, and postimplant bronchoscopy. Thirty-three patients showed at least a one-level improvement in performance status. Of a total of 166 symptoms present prior to therapy, 131 resolved or improved. Approximately 70 percent of a patient's lifetime was rendered symptom improved or symptom free. A roentgenographic reaeration response of 30/41 (73 percent) was achieved. The average FEV1 and FVC improved from 1.5 to 2.1 L and from 2.3 to 2.9 L, respectively. Posttherapy bronchoscopy was performed between one and two months following the implant in 15 patients who agreed to undergo the procedure. Eleven (73 percent) of 15 had complete tumor regression. Major long-term complications were noted in seven patients. Endobronchial radiation, therefore, appears to be a safe and effective technique to palliate malignant airway occlusion.

Mehta, M.; Shahabi, S.; Jarjour, N.; Steinmetz, M.; Kubsad, S. (Univ. of Wisconsin Medical School, Madison (USA))

1990-03-01

314

Subacute brain atrophy after radiation therapy for malignant brain tumor  

SciTech Connect

Brain atrophy with mental and neurologic deterioration developing a few months after radiation therapy in patients without residual or recurrent brain tumors has been recognized. Two illustrative case reports of this pathologic entity are presented. Six autopsy cases with this entity including the two cases were reviewed neurologically, radiographically, and histopathologically. All patients presented progressive disturbances of mental status and consciousness, akinesia, and tremor-like involuntary movement. Computerized tomography (CT) demonstrated marked enlargement of the ventricles, moderate widening of the cortical sulci, and a moderately attenuated CT number for the white matter in all six patients. Four of the six patients had CSF drainage (ventriculoperitoneal shunt or continuous lumbar drainage), however, none of them improved. Histologic examination demonstrated swelling and loss of the myelin sheath in the white matter in all patients, and reactive astrocytosis in three of the six patients. Neither prominent neuronal loss in the cerebral cortex or basal ganglia, nor axonal loss in the white matter was generally identified. The blood vessels of the cerebral cortex and white matter were normal. Ependymal layer and the surrounding brain tissue were normal in all patients. These findings suggested that this pathologic condition results from demyelination secondary to direct neurotoxic effect of irradiation. The authors' previous report was reviewed and the differential diagnoses, the risk factors for this pathologic entity, and the indication for radiation therapy in aged patients with a malignant brain tumor are discussed.

Asai, A.; Matsutani, M.; Kohno, T.; Nakamura, O.; Tanaka, H.; Fujimaki, T.; Funada, N.; Matsuda, T.; Nagata, K.; Takakura, K.

1989-05-15

315

Outcome and Prognostic Factors of Radiation Therapy for Medulloblastoma  

SciTech Connect

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. 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.

Rieken, Stefan, E-mail: Stefan.Rieken@med.uni-heidelberg.de [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany); Mohr, Angela; Habermehl, Daniel; Welzel, Thomas; Lindel, Katja [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany); Witt, Olaf; Kulozik, Andreas E. [Department of Pediatric Oncology, Hematology, Immunology, and Pneumatology, University of Heidelberg, Heidelberg (Germany); Wick, Wolfgang [Department of Neurooncology, University of Heidelberg, Heidelberg (Germany); Debus, Juergen; Combs, Stephanie E. [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany)

2011-11-01

316

Predicting Behavioral Problems in Craniopharyngioma Survivors after Conformal Radiation Therapy  

PubMed Central

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.

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

2009-01-01

317

Quality Assurance of Intensity-Modulated Radiation Therapy  

SciTech Connect

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.

Palta, Jatinder R. [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)], E-mail: paltajr@ufl.edu; Liu, Chihray; Li, Jonathan G. [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)

2008-05-01

318

Adjuvant radiation therapy in metastatic lymph nodes from melanoma  

PubMed Central

Purpose To analyze the outcome after adjuvant radiation therapy with standard fractionation regimen in metastatic lymph nodes (LN) from cutaneous melanoma. Patients and methods 86 successive patients (57 men) were treated for locally advanced melanoma in our institution. 60 patients (69%) underwent LN dissection followed by radiation therapy (RT), while 26 patients (31%) had no radiotherapy. Results The median number of resected LN was 12 (1 to 36) with 2 metastases (1 to 28). Median survival after the first relapse was 31.8 months. Extracapsular extension was a significant prognostic factor for regional control (p = 0.019). Median total dose was 50 Gy (30 to 70 Gy). A standard fractionation regimen was used (2 Gy/fraction). Median number of fractions was 25 (10 to 44 fractions). Patients were treated with five fractions/week. Patients with extracapsular extension treated with surgery followed by RT (total dose ?50 Gy) had a better regional control than patients treated by surgery followed by RT with a total dose <50 Gy (80% vs. 35% at 5-year follow-up; p = 0.004). Conclusion Adjuvant radiotherapy was able to increase regional control in targeted sub-population (LN with extracapsular extension).

2011-01-01

319

Brain tumors and synchrotron radiation: Methodological developments in quantitative brain perfusion imaging and radiation therapy  

SciTech Connect

High-grade gliomas are the most frequent type of primary brain tumors in adults. Unfortunately, the management of glioblastomas is still mainly palliative and remains a difficult challenge, despite advances in brain tumor molecular biology and in some emerging therapies. Synchrotron radiation opens fields for medical imaging and radiation therapy by using monochromatic intense x-ray beams. It is now well known that angiogenesis plays a critical role in the tumor growth process and that brain perfusion is representative of the tumor mitotic activity. Synchrotron radiation quantitative computed tomography (SRCT) is one of the most accurate techniques for measuring in vivo contrast agent concentration and thus computing precise and accurate absolute values of the brain perfusion key parameters. The methodological developments of SRCT absolute brain perfusion measurements as well as their preclinical validation are detailed in this thesis. In particular, absolute cerebral volume and blood brain barrier permeability high-resolution (pixel size <50x50 {mu}m{sup 2}) parametric maps were reported. In conventional radiotherapy, the treatment of these tumors remains a delicate challenge, because the damages to the surrounding normal brain tissue limit the amount of radiation that can be delivered. One strategy to overcome this limitation is to infuse an iodinated contrast agent to the patient during the irradiation. The contrast agent accumulates in the tumor, through the broken blood brain barrier, and the irradiation is performed with kilovoltage x rays, in tomography mode, the tumor being located at the center of rotation and the beam size adjusted to the tumor dimensions. The dose enhancement results from the photoelectric effect on the heavy element and from the irradiation geometry. Synchrotron beams, providing high intensity, tunable monochromatic x rays, are ideal for this treatment. The beam properties allow the selection of monochromatic irradiation, at the optimal energy, for a maximal dose deposit in the tumor, while sparing healthy tissues. The methodology, the associated dosimetry as well as the preclinical validation of iodine enhanced strereotactic synchrotron radiation therapy is developed in the thesis. Significant survival increases were obtained, especially when the delivery of iodine is coupled with a transient blood-brain-barrier opener. The two complementary methods developed in this thesis offer perspectives in the understanding of the glioma growth process and in their treatment by radiation therapy. They show the potential of synchrotron radiation for absolute high-resolution morphological and functional CT imaging, and for new therapeutic modalities using intense monochromatic x rays.

Adam, Jean-Francois [INSERM unite 647-RSRM, ESRF, 6, rue Jules Horrowitz, 38043 Grenoble Cedex (France)

2005-04-01

320

Symptomatic and asymptomatic carotid artery plaque  

PubMed Central

Carotid atherosclerotic plaques represent both stable and unstable atheromatous lesions. Atherosclerotic plaques that are prone to rupture owing to their intrinsic composition such as a large lipid core, thin fibrous cap and intraplaque hemorrhage are associated with subsequent thromboembolic ischemic events. At least 1520% of all ischemic strokes are attributable to carotid artery atherosclerosis. Characterization of plaques may enhance the understanding of natural history and ultimately the treatment of atherosclerotic disease. MRI of carotid plaque and embolic signals during transcranial Doppler have identified features beyond luminal stenosis that are predictive of future transient ischemic attacks and stroke. The value of specific therapies to prevent stroke in symptomatic and asymptomatic patients with severe carotid artery stenosis are the subject of current research and analysis of recently published clinical trials that are discussed in this article.

Mughal, Majid M; Khan, Mohsin K; DeMarco, J Kevin; Majid, Arshad; Shamoun, Fadi; Abela, George S

2011-01-01

321

Adeno-associated Virus Gene Therapy With Cholesterol 24Hydroxylase Reduces the Amyloid Pathology Before or After the Onset of Amyloid Plaques in Mouse Models of Alzheimer's Disease  

Microsoft Academic Search

The development of Alzheimer's disease (AD) is closely connected with cholesterol metabolism. Cholesterol increases the production and deposition of amyloid-? (A?) peptides that result in the formation of amyloid plaques, a hallmark of the pathology. In the brain, cholesterol is synthesized in situ but cannot be degraded nor cross the bloodbrain barrier. The major exportable form of brain cholesterol is

Eloise Hudry; Debby Van Dam; Wim Kulik; Peter P De Deyn; Femke S Stet; Ornella Ahouansou; Abdellatif Benraiss; Andr Delacourte; Pierre Bougnres; Patrick Aubourg; Nathalie Cartier

2010-01-01

322

Results of conservative surgery and radiation therapy for breast cancer  

SciTech Connect

For stage I or II breast cancer, conservative surgery and radiation therapy are as effective as modified radical or radical mastectomy. In most cases, cosmetic considerations and the availability of therapy are the primary concerns. The extent of a surgical resection less than a mastectomy has not been a subject of a randomized trial and is controversial. It appears that removal of a quadrant of the breast for small lesions is safe but excessive. It may be possible to limit the breast resection to gross tumor removal for most patients while using wider resections for patients with an extensive intraductal component or for invasive lobular carcinoma. It also appears that excluding patients from breast conservation on the basis of positive margins on the first attempt at tumor excision may be unnecessarily restrictive. Although patients with an extensive intraductal component or invasive lobular carcinoma should have negative margins, it appears that a patient with predominantly invasive ductal carcinoma can be treated without re-excision if all gross tumor has been resected and there is no reason to suspect extensive microscopic disease. Patients with indeterminate margins should have a re-excision. Axillary dissection provides prognostic information and prevents progression of the disease within the axilla. Axillary dissections limited to level I will accurately identify a substantial number of patients who have pathologically positive but clinically negative nodes. When combined with radiation therapy to the axilla, a level I dissection results in a limited number of patients with progressive axillary disease. Patients with pathologically positive axillas and patients at particularly high risk for systemic disease because of the extent of axillary node involvement can be identified by dissections of levels I and II. 60 references.

Osteen, R.T.; Smith, B.L. (Harvard Medical School, Boston, MA (USA))

1990-10-01

323

Dose Increments in Ionizing Radiation Therapy in Tissues Immediately Adjacent to Metallic Dental Prostheses.  

National Technical Information Service (NTIS)

Radiation therapy in the area of the jaws and face may have harmful side effects on the tissues next to metallic dental prostheses because they increase the radiation dose. Different kinds of radiation were investigated (x-rays, gamma radiation, electron ...

U. Leischner

1983-01-01

324

Ultrasound Thermometry for Therapy-level Radiation Dosimetry  

NASA Astrophysics Data System (ADS)

Radiation oncology is the process of administering a specified dose of radiation to a patient currently receiving treatment for a form of cancer. In this process, it is vital to know the delivered dose for a given radiation beam to correctly treat a patient. The primary reference standard for absorbed dose is established using water calorimetry. The absorbed dose, typically of order 1 Gy (J/kg) at therapy levels, is realized by measuring sub-millikelvin temperature changes using a thermistor in a sensitive Wheatstone bridge. Ultrasound technology has been investigated as an alternative to thermistor measurements since the speed of sound propagation in water varies with temperature. With ultrasonic time-of-flight and highly sensitive phase detection techniques, temperature sensitivity comparable to that of the thermistor bridge has been achieved without introducing non-water materials into the test area. A single ultrasound transducer transmitting and receiving at 5.0 MHz throughout the length of the water phantom, and the phase change of the sound wave was used to determine temperature increase from an irradiative source at specified depths of the phantom. In this experiment, the exposure period was varied from 15s to 160s cyclically by modulating a heat lamp, and a profile of the measured temperature response as a function of the period was obtained using Fourier analysis. Due to the large temperature gradient in the water phantom, measurements are prone to convection which was indeed observed and will be discussed.

Taylor, Courtney

2010-03-01

325

Stereotactic multibeam radiation therapy system in a PACS environment  

NASA Astrophysics Data System (ADS)

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.

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

1991-05-01

326

Treatment of cholangiocarcinoma with oncolytic herpes simplex virus combined with external beam radiation therapy.  

PubMed

Replication-competent oncolytic herpes simplex viruses (HSV), modified by deletion of certain viral growth genes, can selectively target malignant cells. The viral growth gene gamma(1)34.5 has significant homology to GADD34 (growth arrest and DNA damage protein 34), which promotes cell cycle arrest and DNA repair in response to stressors such as radiation (XRT). By upregulating GADD34, XRT may result in greater oncolytic activity of HSV strains deficient in the gamma(1)34.5 gene. The human cholangiocarcinoma cell lines KMBC, SK-ChA-1 and YoMi were treated with NV1023, an oncolytic HSV lacking one copy of gamma(1)34.5. Viral proliferation assays were performed at a multiplicity of infection (MOI, number of viral particles per tumor cell) equal to 1, either alone or after XRT at 250 or 500 cGy. Viral replication was assessed by plaque assay. In vitro cytotoxicity assays were performed using virus at MOIs of 0.01 and 0.1, with or without XRT at 250 cGy and cell survival determined with lactate dehydrogenase assay. Established flank tumors in athymic mice were treated with a single intratumoral injection of virus (10(3) or 10(4) plaque forming units), either alone or after a single dose of XRT at 500 cGy, and tumor volumes measured. RT-PCR was used to measure GADD34 mRNA levels in all cell lines after a single dose of XRT at 250 or 500 cGy. NV1023 was tumoricidal in all three cell lines, but sensitivity to the virus varied. XRT enhanced viral replication in vitro in all cell lines. Combination treatment with low-dose XRT and virus was highly tumoricidal, both in vitro and in vivo. The greatest tumor volume reduction with combination therapy was seen with YoMi cells, the only cell line with increased GADD34 expression after XRT and the only cell line in which a synergistic treatment effect was suggested. In KMBC and SK-ChA-1 cells, neither of which showed increased GADD34 expression after XRT, tumor volume reduction was less pronounced and there was no suggestion of a synergistic effect in either case. Oncolytic HSV are effective in treating human cholangiocarcinoma cell lines, although sensitivity to virus varies. XRT-enhanced viral replication occurs through a mechanism that is not necessarily dependent on GADD34 upregulation. However, XRT-induced upregulation of GADD34 further promotes tumoricidal activity in viral strains deficient in the gamma(1)34.5 gene, resulting in treatment synergy; this effect is cell type dependent. Combined XRT and oncolytic viral therapy is a potentially important treatment strategy that may enhance the therapeutic ratios of both individual therapies. PMID:16138120

Jarnagin, W R; Zager, J S; Hezel, M; Stanziale, S F; Adusumilli, P S; Gonen, M; Ebright, M I; Culliford, A; Gusani, N J; Fong, Y

2006-03-01

327

Radiation therapy in Hodgkin's disease - decades of steady progress.  

PubMed

The treatment of lymphoproliferative diseases has changed dramatically during the last decades. The improved therapeutic results for this disease group are included among the most important achievements of modern oncohaematology. They are due to better disease staging, use of new markers for risk assessment, patient stratification in separate risk groups, implementation of highly effective chemotherapy (CHT), progress of targeted therapies using monoclonal antibodies, proteasome inhibitors, modern radiation therapy (RT) and supportive care. The achieved progress, especially in the treatment of Hodgkin's disease (HD), is an example of the fundamental dependence of clinical practice on the scientific achievements, mainly in the field of diagnostics and in the two pure anticancer therapeutic modalities: chemo- and radiotherapy. The aim of this article was to discuss the basic variants of RT in the multimodal treatment of HD and the clinical experience accumulated during the last decades. The experience gained in the area of involved field RT (IFRT) and extended field RT (EFRT), both alone or as a part of the combined-therapy protocols, is considered in detail. The role of RT is also discussed as a part of the dose-escalated CHT combined programmes for patients recurring, progressing or partially responding to treatment, carried out mainly as IFRT, total lymphoid irradiation (TLI) or total body irradiation (TBI). Regardless of the already attained achievements of the combined treatment at the present stage of development of oncological knowledge, there is still no consensus with respect to the optimal therapy of HD in children and in adult patients. New trials addressing issues of the best modality, best RT technique, optimal dose of RT, optimal number of cycles and timing of CHT are still needed. The contemporary challenge is to optimize treatment so that it can be accomplished with the least toxicity, lowest cost, and greatest efficiency possible. PMID:20658714

Gocheva, L

328

Combined radiation and gene therapy for brain tumors with adenovirus-mediated transfer of cytosine deaminase and uracil phosphoribosyltransferase genes  

Microsoft Academic Search

Radiation therapy is an established modality for the treatment of malignant gliomas. Several reports have shown the advantage of additional radiation in combination with gene therapy. In this study, we investigated the ability of radiation therapy to enhance 5-fluorocytosine (5-FC)\\/cytosine deaminase (CD) plus uracil phosphoribosyltransferase (UPRT) gene therapy in malignant gliomas. In vitro study suggested evidence of a significant cytotoxic

Hirokazu Kambara; Takashi Tamiya; Yasuhiro Ono; Shinji Ohtsuka; Kinya Terada; Yoshiaki Adachi; Tomotsugu Ichikawa; Hirofumi Hamada; Takashi Ohmoto

2002-01-01

329

Clinical studies on the use of radiation therapy as primary treatment of early breast cancer  

SciTech Connect

The treatment of operable breast cancer by primary radiation therapy instead of mastectomy is undergoing evaluation in the United States and Europe. Retrospective studies of patients treated by primary radiation therapy show that local control and survival rates are comparable to those obtained by mastectomy. Detailed analysis of local failure following primary radiation therapy indicates the importance of excisional biopsy of the primary tumor, moderate doses of radiation to the breast and draining lymph node areas, and the use of a boost to the primary tumor area in maximizing local control. Further, the judicious use of local excision combined with meticulous radiotherapy technique yields highly satisfactory results for the majority of treated patients. Preliminary results from prospective trials also indicate that primary radiation therapy provides both local control and survival rates equivalent to mastectomy. Primary radiation therapy is becoming an increasingly important alternative to mastectomy where surgical and radiotherapeutic expertise are available to optimize both local tumor control and the final cosmetic outcome.

Harris, J.R.; Beadle, G.F.; Hellman, S.

1984-02-01

330

[A case of ductal adenocarcinoma of the prostate treated with endocrine therapy and radiation therapy].  

PubMed

We report a case of ductal adenocarcinoma of the prostate. A 81-year-old man presented with a complaint of microhematuria. Serum prostate specific antigen (PSA) was 18. 44 ng/ml. A cystourethroscopic examination revealed a papillary tumor near the verumontanum. Transurethral resection of the tumor and transrectal prostatic needle biopsy was carried out. The pathological diagnosis was ductal adenocarcinoma and acinar adenocarcinoma of the prostate. The tumor responded to endocrine therapy and radiation therapy. At the follow up at 18 months, the PSA level was in the undetectable range (?0.01 ng/ml), and no reccurence of the tumor was seen. Pathogenesis and management of this rare condition is discussed. PMID:21743285

Suzuki, Takahisa; Shinbo, Hitoshi; Kurita, Yutaka; Furuse, Hiroshi; Mugiya, Soichi; Ozono, Seiichiro

2011-05-01

331

Beneficial effect of combination hormonal therapy administered prior and following external beam radiation therapy in localized prostate cancer  

Microsoft Academic Search

Purpose: The aim of the present study isto investigate whether combined androgen blockade associated with radiation therapy for localized prostate cancer decreases at 12 and 24 months the rate of ppsitive follow-up biopsies and serum PSA compared to radiation therapy alone. This is the report of an interim analysis.Methods and Materials: One hundred and twenty patients with clinical Stage B1-T2a,

Jacques Laverdire; Jos L. Gomez; Leonelo Cusan; Elbio Raul Suburu; Pierre Diamond; Martin Lemay; Bernard Candas; Andr Fortin; Fernand Labrie

1997-01-01

332

Carcinoma of the nasal vestibule treated with radiation therapy  

SciTech Connect

Twenty-two patients with squamous carcinoma of the nasal vestibule were treated at the University of Florida Division of Radiation Therapy with curative intent. Fifteen lesions were de novo and seven recurrent after surgery. By AJCC classification, 7 lesions were Tx or T1, 2 were T2, 2 were T3, and 11 were T4. Management of the primary tumor and regional lymphatic drainage was highly individualized. Local control was achieved in 19 out of 22 lesions. The ultimate regional lymph node control rate was 22 out of 22, although two patients required radical neck dissection after development of lymph node disease in untreated regional lymphatics. Two patients have died of cancer and three of intercurrent disease. Cosmetic results are generally excellent but may be compromised by previous surgery in recurrent lesions or tumor destruction of normal tissues in advanced lesions. Complications of treatment are minimal.

Mendenhall, N.P.; Parsons, J.T.; Cassisi, N.J.; Million, R.R.

1987-05-01

333

Effects of radiation therapy on skeletal growth in childhood  

SciTech Connect

Ionizing radiation was used to treat childhood cancer long before the advent of chemotherapy, and it took little time for physicians to appreciate the deleterious effects it had on skeletal growth. The cause of this complication results predominantly from alteration of chondroblastic activity. This may stem directly from irradiation at the epiphyseal plate or indirectly from irradiation of glands that secrete growth-mediating hormones. The complication can go far beyond the obvious physical afflictions and extend into the psychologic domain, rendering deeper, more permanent scars. Presently, many of these effects are predictable, reducible, and treatable without compromising the cure that so often depends on the use of irradiation. Because of the complexities of childhood cancer therapy, strategies aimed at diminishing these effects are challenging. It is imperative that these effects be understood so that they can be reduced in current patients and prevented in future patients.33 references.

Goldwein, J.W. (Univ. of Pennsylvania School of Medicine, Philadelphia (USA))

1991-01-01

334

Commissioning and implementation of an implantable dosimeter for radiation therapy.  

PubMed

In this article we describe commissioning and implementation procedures for the Dose Verification System (DVS) with permanently implanted in vivo wireless, telemetric radiation dosimeters for absolute dose measurements. The dosimeter uses a semiconductor device called a metal-oxide semiconductor field-effect transistor (MOSFET) to measure radiation dose. A MOSFET is a transistor that is generally used for amplifying or switching electronic signals. The implantable dosimeter was implemented with the goal of verifying the dose delivered to radiation therapy patients. For the purpose of acceptance testing, commissioning, and clinical implementation and to evaluate characteristics of the dosimeter, the following tests were performed: 1) temperature dependence, 2) reproducibility,3) field size dependence, 4) postirradiation signal drift, 5) dependence on average dose rate, 6) linearity test, 7) angular dependence (different gantry angle position), 8) angular dependence (different DVS angle position), 9) dose rate dependence,10) irradiation depth dependence, 11) effect of cone-beam exposure to the dosimeter, and 12) multiple reading effect. The dosimeter is not currently calibrated for use in the kV range; nonetheless, the effect of the cone-beam procedure on the MOSFET dosimeter was investigated. Phantom studies were performed in both air and water using an Elekta Synergy S Beam-Modulator linear accelerator. Commissioning and clinical implementation for prostate cancer patients receiving external-beam radiation therapy were performed in compliance with the general recommendations given for in vivo dosimetry devices. The reproducibility test in water at human body temperature (37C) showed a 1.4% absolute difference, with a standard deviation of 5.72 cGy (i.e., SD = 2.9%). The constancy test shows that the average readings at room temperature were 3% lower compared to the readings at human body temperature, with a SD = 2%. Measurements were not dependent upon field size. Due to postirradiation signal drift, the following corrections are suggested: -2.8%, -2%, 0.5%, and 2.5% for the readings taken after 0.5, 1, 5, or 10 min, respectively. Different gantry angles did not influence the readings. The maximum error was less than 1% with a maximum SD = 3.61 cGy (1.8%) for the gantry angle of 45. However, readings are dependent on the dosimeter orientation. The average dose reading was 7.89 cGy (SD = 1.46 cGy) when CBCT imaging was used for the pelvis protocol, and when postirradiation measurement was taken at 2.5 min (expected 2-3 cGy). The clinical implementation of the implantable MOSFET dosimeters for prostate cancer radiation therapy is described. Measurements performed for commissioning show that the dosimeter, if used within specifications, provides sufficient accuracy for its intended use in clinical procedures. The postradiation signal drift, temperature dependence, variation of reproducibility, and rotational isotropy could be encountered if the dosimeter is used outside the manufacturer's specifications. The dosimeter can be used as a tool for quantifying dose at depth, as well as to evaluate adherence between planned doses and the delivered doses. Currently, the system is clinically implemented with 7% tolerance. PMID:23470929

Buzurovic, Ivan; Showalter, Timothy N; Studenski, Matthew T; Den, Robert B; Dicker, Adam P; Cao, Junsheng; Xiao, Ying; Yu, Yan; Harrison, Amy

2013-03-04

335

Polarity Therapy for Cancer-Related Fatigue in Patients With Breast Cancer Receiving Radiation Therapy: A Randomized Controlled Pilot Study  

Microsoft Academic Search

Background. Cancer-related fatigue (CRF) is the most frequently reported side effect of cancer and its treatment. In previous research, Polarity Therapy (PT), an energy therapy, was shown to reduce CRF in patients receiving radiation. This study reports on a small randomized clinical trial designed to collect preliminary data on the efficacy of PT compared with an active control (massage) and

Karen M. Mustian; Joseph A. Roscoe; Oxana G. Palesh; Lisa K. Sprod; Charles E. Heckler; Luke J. Peppone; Kenneth Y. Usuki; Marilyn N. Ling; Ralph A. Brasacchio; Gary R. Morrow

2011-01-01

336

Dynamic optical modulation of the electron beam for the high performance intensity modulated radiation therapy  

Microsoft Academic Search

The radiation therapy of cancer is developing to non-uniform irradiation as intensity modulated radiation therapy (IMRT), reducing the dose to normal tissue and concentrating the dose to cancer tissue. A photocathode RF gun is able to generate a low emittance electron beam pulse using laser light. We thought that a photocathode RF gun can generate an intensity-modulated electron beam by

T. Kondoh; H. Kashima; J. Yang; Y. Yoshida

2007-01-01

337

Global Impact: An Examination of a Caribbean Radiation Therapy Student Placement at a Canadian Teaching Hospital  

Microsoft Academic Search

This paper examines the impact of a nine-week overseas clinical placement at a Canadian teaching hospital on second-year radiation therapy students from Trinidad and Tobago. The placement allowed the students to accumulate specific technical competencies and experience other aspects of Canadian radiation therapy professionalism such as patient education and assessment, quality assurance and academic activities. The evaluation of the visit

Amanda Bolderston; Susan Morgan

2010-01-01

338

Radiation therapy planning with photons and protons for early and advanced breast cancer: an overview  

Microsoft Academic Search

Postoperative radiation therapy substantially decreases local relapse and moderately reduces breast cancer mortality, but can be associated with increased late mortality due to cardiovascular morbidity and secondary malignancies. Sophistication of breast irradiation techniques, including conformal radiotherapy and intensity modulated radiation therapy, has been shown to markedly reduce cardiac and lung irradiation. The delivery of more conformal treatment can also be

Damien C Weber; Carmen Ares; Antony J Lomax; John M Kurtz

2006-01-01

339

Value of extended field radiation therapy in carcinoma of the prostate  

Microsoft Academic Search

Since 1970, a total of 342 patients have receive radial radiation therapy for carcinoma of the prostate. The estimated 5 year survival of 78% and 5 year disease-free survival of 67% remains unchanged. Initially, all patients received radiation therapy to the prostate. Recently, patients with more advanced disease as well as a selected group of patients with less extensive disease

David G. McGowan

1981-01-01

340

Solitary angiokeratoma of the tongue in an adult patient treated with intensity modulated radiation therapy.  

PubMed

A solitary mucosal angiokeratoma is an extremely rare presentation. In this report, we present a 67-year-old woman with a 3cm solitary angiokeratoma involving the tongue, who was treated with intensity modulated radiation therapy after declining surgery. The patient is alive and free of disease at 1.5years following radiation therapy. PMID:23410904

Erkal, Eda Yirmibe?o?lu; Karabey, M Sinan; Vural, Ci?dem; Mutlu, Fatih; Aksu, Grkem; Sarper, Binnaz; Akansel, Gr

2013-02-11

341

Seminar article Benchmarks achieved in the delivery of radiation therapy for muscle-invasive bladder cancer  

Microsoft Academic Search

Radiation therapy has a multifaceted role in the treatment of muscle-invasive bladder cancer, from being a component of bladder sparing regimens to adjuvant therapy for patients after partial cystectomy, to palliative treatment in patients with metastatic disease. Here, we review the techniques currently used and the settings in which these techniques are applied. Advances in imaging and radiation delivery have

John J. Coen; Anthony L. Zietman; Donald S. Kaufman; William U. Shipley

342

Microdosimetry for Microbeam Radiation Therapy (MRT): theoretical calculations using the Monte Carlo toolkit  

Microsoft Academic Search

Radiation therapy is widely used in the treatment of very different types of cancer. Recent developments in this field are aiming at delivering high doses to the target volume while sparing the surrounding healthy tissues. The microbeam radiation therapy (MRT) is a new kind of radiotherapy which could be used for treating infantile brain tumors, as other kinds of radiotherapy

J. Spiga; E. A. Siegbahn; E. Brauer-Krisch; P. Randaccio; A. Bravin

2006-01-01

343

Low-Dose Neoadjuvant External Beam Radiation Therapy for Soft Tissue Sarcoma  

Microsoft Academic Search

Purpose: For soft tissue sarcoma, neoadjuvant external beam radiation therapy (EBRT) to 50 Gy has the same local control (LC) and overall survival as postoperative radiation therapy (PORT) to 60 Gy, but with increased wound complications. We examined whether low-dose neoadjuvant EBRT would decrease acute toxicity while maintaining LC. Methods and Materials: From 1971 to 2008, 1,765 patients with nonmetastatic

Kiran Devisetty; Wendy Kobayashi; Herman D. Suit; Saveli I. Goldberg; Andrzej Niemierko; Yen-Lin E. Chen; Kevin A. Raskin; Joseph H. Schwab; Dempsey S. Springfield; Sam S. Yoon; Francis J. Hornicek; Thomas F. DeLaney

2011-01-01

344

Combined iridium 192 interstitial and external beam radiation therapy for the treatment of prostatic cancer  

Microsoft Academic Search

Twenty-four patients with clinically palpable prostatic adenocarcinoma (stage B or C) were treated with a combination of interstitial radiation therapy and external beam radiation therapy following pelvic lymphadenectomy for accurate staging. Early results indicate a complete clinical response rate at 12 months of 77%, with a 4% complication rate (persisting rectal ulceration).

B. S. Clubb; J. L. Summers

2009-01-01

345

Progression and complications after external beam radiation therapy for carcinoma of prostate  

Microsoft Academic Search

Sixty patients with prostatic carcinoma localized to the pelvis have been treated by external beam radiation therapy: 2 patients (2%) were Stage A, 12 (20%) Stage B, 14 (23%) Stage C, and 32 (53%) Stage D1. Twenty-two patients received adjuvant therapy (11 estramustine phosphate (Estracyt) and 11 cyclophosphamide (Cytoxan)) after radiation. Progression occurred in 22 patients (37%): 6 (10%) had

Maurizio Brausi; Mark S. Soloway

1989-01-01

346

On bolus for megavoltage photon and electron radiation therapy.  

PubMed

Frequently, in radiation therapy one must treat superficial lesions on cancer patients; these are at or adjacent to the skin. Megavoltage photon radiotherapy penetrates through the skin to irradiate deep-seated tumors, with skin-sparing property. Hence, to treat superficial lesions, one must use a layer of scattering material to feign as the skin surface. Although megavoltage electron beams are used for superficial treatments, one occasionally needs to enhance the dose near the surface. Such is the function of a "bolus," a natural or synthetically developed material that acts as a layer of tissue to provide a more effective treatment to the superficial lesions. Other uses of boluses are to correct for varying surface contours and to add scattering material around the patient's surface. Materials used as bolus vary from simple water to metal and include various mixtures and compounds. Even with the modernization of the technology for external-beam therapy and the emergence of various commercial boluses, the preparation and utilization of a bolus in clinical radiotherapy remains an art. Considering the varying experiences and practices, this paper briefly summarizes available boluses that have been proposed and are employed in clinical radiotherapy. Although this review is not exhaustive, it provides some initial guidance and answers questions that may arise in clinical practice. PMID:23582702

Vyas, Vedang; Palmer, Lisa; Mudge, Ray; Jiang, Runqing; Fleck, Andre; Schaly, Bryan; Osei, Ernest; Charland, Paule

2013-04-09

347

Automated fiducial marker planning for thoracic stereotactic body radiation therapy  

NASA Astrophysics Data System (ADS)

Stereotactic body-radiation therapy (SBRT) has gained acceptance in treating lung cancer. Localization of a thoracic lesion is challenging as tumors can move significantly with breathing. Some SBRT systems compensate for tumor motion with the intrafraction tracking of targets by two stereo fluoroscopy cameras. However, many lung tumors lack a fluoroscopic signature and cannot be directly tracked. Small radiopaque fiducial markers, acting as fluoroscopically visible surrogates, are instead implanted nearby. The spacing and configuration of the fiducial markers is important to the success of the therapy as SBRT systems impose constraints on the geometry of a fiducial-marker constellation. It is difficult even for experienced physicians mentally assess the validity of a constellation a priori. To address this challenge, we present the first automated planning system for bronchoscopic fiducial-marker placement. Fiducial-marker planning is posed as a constrained combinatoric optimization problem. Constraints include requiring access from a navigable airway, having sufficient separation in the fluoroscopic imaging planes to resolve each individual marker, and avoidance of major blood vessels. Automated fiducial-marker planning takes approximately fifteen seconds, fitting within the clinical workflow. The resulting locations are integrated into a virtual bronchoscopic planning system, which provides guidance to each location during the implantation procedure. To date, we have retrospectively planned over 50 targets for treatment, and have implanted markers according to the automated plan in one patient who then underwent SBRT treatment. To our knowledge, this approach is the first to address automated bronchoscopic fiducialmarker planning for SBRT.

Gibbs, Jason D.; Rai, Lav; Wibowo, Henky; Tsalyuk, Serge; Anderson, Eric D.

2012-02-01

348

Gadolinium dose enhancement studies in microbeam radiation therapy.  

PubMed

Microbeam radiation therapy (MRT) is an innovative technique to treat brain tumors. The synchrotron generated x-ray beam, used for the treatment, is collimated and delivered in an array of narrow micrometer-sized planar rectangular fields. Several preclinical experiments performed at the Brookhaven National Laboratory (BNL) and at the European Synchrotron Radiation Facility (ESRF) have shown the sparing effect of the healthy tissue and the ablation of tumors in several animal models. It has also been determined that MRT yields a higher therapeutic index than nonsegmented beams of the same energy. This therapeutic index could be greatly improved by loading the tumor with high atomic number (Z) contrast agents. In this work, the dose enhancement factors and the peak to valley dose ratios (PVDRs) are assessed for different gadolinium (Z = 64) concentrations in the tumor and different microbeam energies by using Monte Carlo simulations (PENELOPE 2006 code). A significant decrease in the PVDR values in the tumor, and therefore a relevant increase in the dose deposition, is found in the presence of gadolinium. The optimum energy for the dose deposition in the tumor while keeping a high PVDR in the healthy tissues, which guaranties their sparing, has been investigated. PMID:19746791

Prezado, Y; Fois, G; Le Duc, G; Bravin, A

2009-08-01

349

Pitfalls in normalization for intensity-modulated radiation therapy planning  

SciTech Connect

Three-dimensional (3D) treatment planning often involves complex combinations of beam energies, treatment fields, and beam modifying devices. Even when a plan is devised that meets many treatment-planning objectives, limitations in the planner's ability to further adjust beam characteristics may require the radiation dose prescription to be normalized to an isodose level that best covers the target volume. While these normalizations help meet the volume coverage goals, they also result in adjustment of the dose delivered to the normal tissues and must be carefully evaluated. Intensity-modulated radiation therapy (IMRT) treatment planning allows combinations of complex dose patterns, in order to achieve the desired treatment planning goals. These dose patterns are created by defining a set of treatment planning objectives and then allowing the treatment planning computer to create intensity patterns, through the use of moving multileaf collimation that will meet the requested goals. Often, when an IMRT treatment plan is created that meets many of the treatment planning goals but falls short of volume coverage requirements, the planner is tempted to apply normalization principles similar to those utilized with 3D treatment planning. Again, these normalizations help meet the volume coverage goals, but unlike 3D planning situations, may result in avoidable delivery of additional doses to the normal tissues. The focus of this study is to evaluate the effect of application of normalization for IMRT planning using multiple patient situations. Recommendations would favor re-optimization over normalization in most planning situations.

Williams, Greg [Huntsman Cancer Hospital, University of Utah Health Science Center, Salt Lake City, UT (United States)]. E-mail: greg.williams@hci.utah.edu; Tobler, Matt [Huntsman Cancer Hospital, University of Utah Health Science Center, Salt Lake City, UT (United States); Leavitt, Dennis [Huntsman Cancer Hospital, University of Utah Health Science Center, Salt Lake City, UT (United States)

2005-01-01

350

[Normal tissue tolerance to external beam radiation therapy: spinal cord].  

PubMed

Radiation myelopathy is one of the most dreadful complications of radiation therapy. Despite multiple animal experiments and human autopsic series, its pathogenesis remains largely unknown. In most instances, the classical aspect of myelomalacy combines glial and vascular injuries in various sequences. Recent studies point out the role of oligodendrocytes and their precusors, as well as of intercellular mediators (cytokines and stress molecules). The clinical presentation comprises a spectrum of non specific neurological symptoms whose evolution is sometimes regressive but more commonly progressive and life-threatening. Usually, it occurs following a latent period of six months to two years after irradiation of the cervical, thoracic or upper lumbar spine to a dose in excess of 50 Gy, conventionally fractionated. Nonetheless, these typical features can be altered by extrinsic factors, such as hypofractionation/acceleration of the dose, multiple surgical procedures, chemotherapy especially megatherapy, or neurotoxic drugs. Conversely, hyperfractionated regimens that take into account protracted half-time repair of sublethal damages to the CNS, as well as sophisticated estimates of the dose to the cord and QA programs during the treatment course minimize such risks. PMID:20561809

Habrand, J-L; Drouet, F

2010-06-18

351

Pediatric meuroblastoma: postoperative radiation therapy using less than 2000 rad  

SciTech Connect

There is considerable controversy regarding the role of radiaiton therapy in the treatment of neuroblastoma. Postoperative irradiation in the range of 2500-4000 rad is commonly used in the treatment of Evans Stage II or III disease, but there are no data in the literature to suggest the optimum dose of radiation that is necessary. Because much lower doses have been used at the University of Florida, a retrospective study was undertaken in an attempt to determine the optimum dose necessary in conjunction with surgery. From March 1964 through July 1979, 21 children with Stage II or III neuroblastoma were seen at the University of Florida. One patient died postoperatively. The remainder received postoperative irradiation with doses ranging from 900 to 4500 rad. The lower dose of radiation used did not adversely influence survival, particularly for patients less than two years of age diagnosis. In this group, no patient had a local recurrence or died of disease, even though nine of 15 available patients received doses of 900-1500 rad.

Jacobson, H.M.; Marcus, R.B. Jr; Thar, T.L.; Million, R.R.; Graham-Pole, J.R.; Talbert, J.L.

1983-04-01

352

Stereotactic body radiation therapy: a novel treatment modality.  

PubMed

Stereotactic body radiation therapy (SBRT) involves the delivery of a small number of ultra-high doses of radiation to a target volume using very advanced technology and has emerged as a novel treatment modality for cancer. The role of SBRT is most important at two cancer stages-in early primary cancer and in oligometastatic disease. This modality has been used in the treatment of early-stage non-small-cell lung cancer, prostate cancer, renal-cell carcinoma, and liver cancer, and in the treatment of oligometastases in the lung, liver, and spine. A large body of evidence on the use of SBRT for the treatment of primary and metastatic tumors in various sites has accumulated over the past 10-15 years, and efficacy and safety have been demonstrated. Several prospective clinical trials of SBRT for various sites have been conducted, and several other trials are currently being planned. The results of these clinical trials will better define the role of SBRT in cancer management. This article will review the radiobiologic, technical, and clinical aspects of SBRT. PMID:19997074

Lo, Simon S; Fakiris, Achilles J; Chang, Eric L; Mayr, Nina A; Wang, Jian Z; Papiez, Lech; Teh, Bin S; McGarry, Ronald C; Cardenes, Higinia R; Timmerman, Robert D

2009-12-08

353

Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma.  

PubMed

We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost against the tumour bed) with a conventional fractionation of 2 Gy/day, 5 days per week. RT was applied as hockey-stick portals, also called L-fields. In 2 cases, the symptoms fully resolved. Therapeutic irradiation can cause significant injury to the peripheral nerves of the lumbosacral plexus and/or to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate their frequency and outcome. The treatment of neurological symptoms due to RT is symptomatic. PMID:22949908

Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

2012-08-15

354

Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma  

PubMed Central

We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost against the tumour bed) with a conventional fractionation of 2 Gy/day, 5 days per week. RT was applied as hockey-stick portals, also called L-fields. In 2 cases, the symptoms fully resolved. Therapeutic irradiation can cause significant injury to the peripheral nerves of the lumbosacral plexus and/or to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate their frequency and outcome. The treatment of neurological symptoms due to RT is symptomatic.

Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

2012-01-01

355

Clinical efficacy of respiratory gated conformal radiation therapy.  

PubMed

One major limitation of three-dimensional conformal radiation therapy that has not been adequately addressed is respiration-induced organ motion. During respiration, tumors in the abdomen can typically move from 1 to 3 centimeters. Because the size and shape of external radiation treatment fields do not change during treatment, the field size of the x-ray beam must be enlarged to encompass the tumor through the entire respiration cycle. Several manufacturers are developing respiratory gating systems. These systems allow the selective delivery of absorbed doses to moving target volumes in the abdomen during time intervals when the target volume is within the intended location. Before respiratory gated radiotherapy can be implemented clinically, the efficacy of the procedure must be justified. The magnitude of dosimetric and geometric uncertainties associated with respiratory motion must be identified to determine if gating can provide an advantage over conventional treatment techniques. In addition, clinical situations and specific types of cancer that could benefit from respiratory gating must also be identified. PMID:10379508

Ramsey, C R; Scaperoth, D; Arwood, D; Oliver, A L

1999-01-01

356

Megavoltage Beam Properties Affecting Patient Dose in Radiation Therapy.  

NASA Astrophysics Data System (ADS)

Certain properties of megavoltage beams have remained of concern in radiation therapy. This investigation is directed towards a better characterization of the problems presented by contaminant electrons in these photon beams, by their spectral distribution and by their interaction in a specific target tissue where heterogeneity poses a particular clinical problem. Two megavoltage beams, a ^{60}CO and a 6 MV, are studied. The energy spectrum modified by passing through the collimator is measured using a direct scintillation spectroscopy technique. The electron component is revealed using a sweeping magnet. A specially built pancake charged particle detector makes it possible to measure the fluence and the dose of the contaminant electrons directly. The sweeping magnet is used in the further investigations of these electrons. Dose perturbations at interfaces between surgical steel implants and tissue are analyzed using 20 ?m thick TL dosemeters. The various factors affecting the relative magnitudes of these dose perturbations are discussed. Results show that direct scintillation spectroscopy provides an adequate first measure of the collimator produced energy spectrum. The general applicability of charge detector in the explicit measurement of the fluence and the dose of the contaminant electrons is demonstrated. A gradient effect is observed when the detector is used in conjunction with the sweeping magnet. A 50% contribution to the total patient surface dose by secondarily produced radiation in the machine head assemblage is observed at large field sizes. A maximum dose enhancement of 42% at stainless steel/tissue equivalent material interface is measured using the micron thick TL dosemeters. This enhancement is of sufficient magnitude to produce unacceptable radiation sequelae. The measurements allow the design of clinically acceptable techniques. The dosemeters proved to be of dimension and sensitivity appropriate for precise, and accurate measurement of dose perturbation at interfaces due to metal implants.

Ikoro, Nnaemeka C.

1988-08-01

357

Radiation therapy in proliferative vitreoretinopathy. A prospective randomized study.  

PubMed

In a prospective study of the effect of postoperative radiation therapy for the prevention of reproliferation of membranes and recurrent proliferative vitreoretinopathy (PVR) two similar groups of patients with retinal detachment and PVR grade D1 to D3 in one eye were compared. Half the eyes (30) received a total dose of 3000 cGy after surgery; the other half remained untreated. After a follow-up of 6 months and 14 months or more (maximum 36 months) the anatomical and functional results of each group were compared. After 6 months in the unirradiated group 57% (17/30) remained attached and 43% (13/30) had detached again. In the irradiated group 63% (19/30) were attached and 37% (11/30) had detached. However, there was no statistically significant difference between the two groups (P = 0.479, Fisher's Exact Test). After 14 months the number of cured and uncured eyes remained the same in the unirradiated group, while in four of the eyes in the irradiated group a later onset of reproliferation and detachment occurred (after 7, 8, 12 and 14 months, respectively). A final cure rate of 57% (17/30) was achieved in the unirradiated group and a 50% (15/30) cure rate in the irradiated group. Thus the failure rate was 43% (13/30) in the unirradiated group and 50% (15/30) in the irradiated group (P = 0.473, Fisher's Exact Test). No side effects from the radiation were observed in any case and no radiation retinopathy occurred during an observation period of up to 3 years.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8034208

Binder, S; Bonnet, M; Velikay, M; Gerard, J P; Stolba, U; Wedrich, A; Hohenberg, H

1994-04-01

358

Radiation therapy for the palliation of multiple myeloma  

SciTech Connect

This study reviews the experience at the University of Arizona in an effort to define the minimum effective radiation dose for durable pain relief in the majority of patients with symptomatic multiple myeloma. The records of 101 patients with multiple myeloma irradiated for palliation at the University of Arizona between 1975 and 1990 were reviewed. Three hundred sixteen sites were treated. Ten sites were asymptomatic, including six hemibody fields with advanced disease unresponsive to chemotherapy and four local fields with impending pathological fractures. Three hundred six evaluable symptomatic sites remained. The most common symptom was bone pain. Other symptoms included neurological impairment with a palpable mass. Total tumor dose ranged from 3.0 to 60 Gy, with a mean of 25 Gy. Symptom relief was obtained in 297 of 306 evaluable symptomatic sites (97%). Complete relief of symptoms was obtained in 26% and partial relief in 71%. Symptom relief was obtained in 92% of sites receiving a total dose less than 10 Gy (n = 13) and 98% of sites receiving 10 Gy or more (n = 293). No dose-response could be demonstrated. The likelihood of symptom relief was not influenced by the location of the lesion or the use of concurrent chemotherapy. Of the 297 responding sites, 6% (n = 19) relapsed after a median symptom-free interval of 16 months. Neither the probability of relapse nor the time to relapse was related to the radiation dose. Retreatment of relapsing sites provided effective palliation in all cases. Radiation therapy is effective in palliating local symptoms in multiple myeloma. A total dose of 10 Gy should provide durable symptom relief in the majority of patients. 16 refs., 3 figs., 4 tabs.

Leigh, B.R.; Kurtts, T.A.; Mack, C.F.; Matzner, M.B.; Shimm, D.S. (Univ. of Arizona, Tucson (United States))

1993-04-02

359

Intraoperative electron beam radiation therapy: Technique, dosimetry, and dose specification: Report of task force 48 of the radiation therapy committee, American Association of Physicists in Medicine  

Microsoft Academic Search

Intraoperative radiation therapy (IORT) is a treatment modality whereby a large single dose of radiation is delivered to a surgically open, exposed cancer site. Typically, a beam of megavoltage electrons is directed at an exposed tumor or tumor bed through a specially designed applicator system. In the last few years, IORT facilities have proliferated around the world. The IORT technique

Jatinder R. Palta; Peter J. Biggs; John D. Hazle; M. Saiful Huq; Robert A. Dahl; Timothy G. Ochran; Jerry Soen; Ralph R. Dobelbower; Edwin C. McCullough

1995-01-01

360

Detection of High-Risk Atherosclerotic Plaque  

PubMed Central

The leading cause of major morbidity and mortality in most countries around the world is atherosclerotic cardiovascular disease, most commonly caused by thrombotic occlusion of a high-risk coronary plaque resulting in myocardial infarction or cardiac death, or embolization from a high-risk carotid plaque resulting in stroke. The lesions prone to result in such clinical events are termed vulnerable or high-risk plaques, and their identification may lead to the development of pharmacological and mechanical intervention strategies to prevent such events. Autopsy studies from patients dying of acute myocardial infarction or sudden death have shown that such events typically arise from specific types of atherosclerotic plaques, most commonly the thin-cap fibroatheroma. However, the search in human beings for vulnerable plaques before their becoming symptomatic has been elusive. Recently, the PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree) study demonstrated that coronary plaques that are likely to cause future cardiac events, regardless of angiographic severity, are characterized by large plaque burden and small lumen area and/or are thin-cap fibroatheromas verified by radiofrequency intravascular ultrasound imaging. This study opened the door to identifying additional invasive and noninvasive imaging modalities that may improve detection of high-risk atherosclerotic lesions and patients. Beyond classic risk factors, novel biomarkers and genetic profiling may identify those patients in whom noninvasive imaging for vulnerable plaque screening, followed by invasive imaging for risk confirmation is warranted, and in whom future pharmacological and/or device-based focal or regional therapies may be applied to improve long-term prognosis.

Fleg, Jerome L.; Stone, Gregg W.; Fayad, Zahi A.; Granada, Juan F.; Hatsukami, Thomas S.; Kolodgie, Frank D.; Ohayon, Jacques; Pettigrew, Roderic; Sabatine, Marc S.; Tearney, Guillermo; Waxman, Sergio; Domanski, Michael J.; Srinivas, Pothur R.; Narula, Jagat

2013-01-01

361

Molecular strategies targeting the host component of cancer to enhance tumor response to radiation therapy  

SciTech Connect

The tumor microenvironment, in particular, the tumor vasculature, as an important target for the cytotoxic effects of radiation therapy is an established paradigm for cancer therapy. We review the evidence that the phosphoinositide 3-kinase (PI3K)/Akt pathway is activated in endothelial cells exposed to ionizing radiation (IR) and is a molecular target for the development of novel radiation sensitizing agents. On the basis of this premise, several promising preclinical studies that targeted the inhibition of the PI3K/Akt activation as a potential method of sensitizing the tumor vasculature to the cytotoxic effects of IR have been conducted. An innovative strategy to guide cytotoxic therapy in tumors treated with radiation and PI3K/Akt inhibitors is presented. The evidence supports a need for further investigation of combined-modality therapy that involves radiation therapy and inhibitors of PI3K/Akt pathway as a promising strategy for improving the treatment of patients with cancer.

Kim, Dong Wook [Department of Radiation Oncology, Vanderbilt Ingram Cancer Center, Nashville, TN (United States); Huamani, Jessica [Department of Radiation Oncology, Vanderbilt Ingram Cancer Center, Nashville, TN (United States); Fu, Allie [Department of Radiation Oncology, Vanderbilt Ingram Cancer Center, Nashville, TN (United States); Hallahan, Dennis E. [Department of Radiation Oncology, Vanderbilt Ingram Cancer Center, Nashville, TN (United States)]. E-mail: dennis.hallahan@vanderbilt.edu

2006-01-01

362

Surgical treatment and radiation therapy of frontal lobe meningiomas in 7 dogs  

PubMed Central

The cases of 7 adult dogs with generalized seizures managed by surgical excision and radiation therapy for frontal lobe meningiomas were reviewed. The neurological examination was unremarkable in 6 of the 7 dogs. Five dogs were operated on using a bilateral transfrontal sinus approach and 2 using a unilateral sinotemporal approach to the frontal lobe. One dog was euthanized 14 d after surgery; radiation therapy was initiated 3 wk after surgery in the remaining 6 dogs. Long-term follow-up consisted of neurological examination and magnetic resonance imaging (MRI) and/or computed tomography (CT) scan after radiation therapy. The mean survival time for dogs that had surgery and radiation therapy was 18 mo after surgery. Frontal lobe meningiomas have been associated with poor prognosis. However, the surgical approaches used in these cases, combined with radiation therapy, allow a survival rate for frontal lobe meningiomas similar to that for meningiomas located over the cerebral convexities.

Uriarte, Ane; Moissonnier, Pierre; Thibaud, Jean-Laurent; Reyes-Gomez, Edouard; Devauchelle, Patrick; Blot, Stephane

2011-01-01

363

The efficacy of sucralfate suspension in the prevention of oral mucositis due to radiation therapy  

SciTech Connect

The purpose of this study was to assess the value of sucralfate suspension in prevention of oral mucositis and for reduction of oral pain in patients who develop mucositis during radiation therapy. The study was a double-blind, placebo-controlled, randomized prospective trial of a sucralfate suspension in the prevention and management of oral mucositis during radiation therapy. Oral mucositis was assessed using a quantitative scale and symptoms were assessed using visual analogue scales. The statistical model was developed to detect a 40% reduction in mucositis. No statistically significant reduction in mucositis was seen. Early during radiation therapy less oral pain was reported in the sucralfate group, but as treatment progressed all patients experienced pain. Patients in the sucralfate group were prescribed topical and systemic analgesics later in the course of radiation therapy. Prophylactic oral rinsing with sucralfate did not prevent oral ulcerative mucositis. Sucralfate may reduce the experience of pain during radiation therapy. 32 refs., 3 tabs.

Epstein, J.B.; Wong, F.L.W. (British Columbia Cancer Agency, Vancouver (Canada))

1994-02-01

364

Neutron, Proton, and Photonuclear Cross Sections for Radiation Therapy and Radiation Protection  

SciTech Connect

The authors review recent work at Los Alamos to evaluate neutron, proton, and photonuclear cross section up to 150 MeV (to 250 MeV for protons), based on experimental data and nuclear model calculations. These data are represented in the ENDF format and can be used in computer codes to simulate radiation transport. They permit calculations of absorbed dose in the body from therapy beams, and through use of kerma coefficients allow absorbed dose to be estimated for a given neutron energy distribution. For radiation protection, these data can be used to determine shielding requirements in accelerator environments, and to calculate neutron, proton, gamma-ray, and radionuclide production. Illustrative comparisons of the evaluated cross section and kerma coefficient data with measurements are given.

Chadwick, M.B.

1998-09-10

365

Lung abnormalities at multimodality imaging after radiation therapy for non-small cell lung cancer.  

PubMed

Three-dimensional (3D) conformal radiation therapy (CRT) and stereotactic body radiation therapy (SBRT) are designed to deliver the maximum therapeutic radiation dose to the tumor, allowing improved local disease control, while minimizing irradiation of surrounding normal structures. The complex configuration of the multiple beams that deliver the radiation dose to the tumor in 3D CRT and SBRT produces patterns of lung injury that differ in location and extent from those seen after conventional radiation therapy. Radiation-induced changes in lung tissue after 3D CRT and SBRT occur within the radiation portals. The imaging appearance of irradiated tissues varies according to the time elapsed after the completion of therapy, with acute-phase changes of radiation pneumonitis represented by ground-glass opacities and consolidation and with late-phase changes of radiation fibrosis manifesting as volume loss, consolidation, and traction bronchiectasis. Knowledge of treatment timelines and radiation field locations, as well as familiarity with the full spectrum of possible radiation-induced lung injuries after 3D CRT and SBRT, is important to correctly interpret the abnormalities that may be seen at computed tomography (CT). Differential diagnoses in this context might include infections, lymphangitic carcinomatosis, local recurrence of malignancy, and radiation-induced tumors. The integration of morphologic information obtained at CT with metabolic information obtained at positron emission tomography is helpful in distinguishing radiation-induced parenchymal abnormalities from residual, recurrent, and new cancers. Thus, multimodality follow-up imaging may lead to substantial changes in disease management. PMID:21571656

Larici, Anna Rita; del Ciello, Annemilia; Maggi, Fabio; Santoro, Silvia Immacolata; Meduri, Bruno; Valentini, Vincenzo; Giordano, Alessandro; Bonomo, Lorenzo

366

Radiation-Induced Lymphocyte Apoptosis to Predict Radiation Therapy Late Toxicity in Prostate Cancer Patients  

SciTech Connect

Purpose: 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. Methods and Materials: 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{sub 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. Results: 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. Conclusions: 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.

Schnarr, Kara [Department of Medicine, St. George's University, Grenada, WI (Grenada); Boreham, Douglas [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON (Canada); Sathya, Jinka [Department of Radiation Oncology, University of Manitoba, Winnipeg, MB (Canada); Julian, Jim [Department of Oncology, McMaster University, Hamilton, Ontario (Canada); Dayes, Ian S. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON (Canada); Department of Oncology, McMaster University, Hamilton, Ontario (Canada)], E-mail: Ian.Dayes@jcc.hhsc.ca

2009-08-01

367

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

SciTech Connect

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 included 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.

Knisely, Jonathan P.S. [Department of Therapeutic Radiology, Yale University School of Medicine and Yale Cancer Center, New Haven, CT (United States)], E-mail: jonathan.knisely@yale.edu; Berkey, Brian [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Chakravarti, Arnab [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Yung, Al W.K. [Department of Neuro-Oncology and Brain Tumor Center, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Curran, Walter J. [Department of Radiation Oncology, Emory University, Atlanta, GA (United States); Robins, H. Ian [Department of Human Oncology, University of Wisconsin Medical School, Madison, WI (United States); Department of Medicine, University of Wisconsin Medical School, Madison, WI (United States); Movsas, Benjamin [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Brachman, David G. [Department of Radiation Oncology, AZ Oncology Services and St. Joseph's Hospital, Phoenix, AZ (United States); Henderson, Randall H. [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Mehta, Minesh P. [Department of Medicine, University of Wisconsin Medical School, Madison, WI (United States)

2008-05-01

368

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

SciTech Connect

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. 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.

Kelly, Patrick; Das, Prajnan [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Varadhachary, Gauri R. [Department of Gastrointestinal Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Fontanilla, Hiral P.; Krishnan, Sunil; Delclos, Marc E.; Jhingran, Anuja; Eifel, Patricia J. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Crane, Christopher H., E-mail: ccrane@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2012-04-01

369

UNC study find Intensity Modulated Radiation Therapy optimal for localized prostate cancer  

Cancer.gov

A treatment for localized prostate cancer known as Intensity Modulated Radiation Therapy (IMRT) is better than conventional conformal radiation therapy (CRT) for reducing certain side effects and preventing cancer recurrence, according to a study published in the April 18, 2012 issue of the Journal of the American Medical Association... The study also showed IMRT to be as effective as proton therapy, a newer technique that has grown in popularity in recent years.

370

Fewer weeks of hormone therapy before radiation reduces side effects in intermediate risk prostate cancer  

Cancer.gov

A shorter course of androgen suppression therapy prior to radiation therapy, when compared to a longer course of androgen suppression therapy, yields favorable outcomes and fewer adverse effects for intermediate-risk prostate cancer patients, according to research presented at the American Society for Radiation Oncology's (ASTRO) 55th Annual Meeting by researchers from the Mayo Clinic. The study confirmed a disease-specific-survival (DSS) rate of 95 percent when patients received fewer weeks of neoadjuvant (NEO) total androgen suppression (TAS).

371

Extracranial stereotactic radiation therapy: set-up accuracy of patients treated for liver metastases  

Microsoft Academic Search

Purpose: Patients with liver metastases might benefit from high-dose conformal radiation therapy. A high accuracy of repositioning and a reduction of target movement are necessary for such an approach. The set-up accuracy of patients with liver metastases treated with stereotactic single dose radiation was evaluated.Methods and Materials: Twenty-four patients with liver metastases were treated with single dose radiation therapy on

K. K Herfarth; J Debus; F Lohr; M. L Bahner; P Fritz; A Hss; W Schlegel; M. F Wannenmacher

2000-01-01

372

Positron emission tomography with fluorodeoxyglucose to evaluate tumor response and control after radiation therapy  

Microsoft Academic Search

Following radiation therapy, evaluation of viable tumor can often be difficult with anatomic imaging criteria (tumor size alone). In this study, the utility of biochemical imaging with the glucose analog 2-[F-18]fluoro-2-deoxy-D-glucose and positron emission tomography was investigated in patients with radiation therapy. Post-radiation positron emission tomography with 2-[F-18]fluoro-2-deoxy-D-glucose studies were done in all patients, with 9 head and neck patients

Lisa Chaiken; G. Juillard; S. Rege; C. Hoh; Y. Choi; B. Jabour; Randall Hawkins; Robert Parker

1993-01-01

373

Gold nanoparticles enhance the radiation therapy of a murine squamous cell carcinoma  

Microsoft Academic Search

The purpose of this study is to test the hypothesis that gold nanoparticle (AuNP, nanogold)-enhanced radiation therapy (nanogold radiation therapy, NRT) is efficacious when treating the radiation resistant and highly aggressive mouse head and neck squamous cell carcinoma model, SCCVII, and to identify parameters influencing the efficacy of NRT. Subcutaneous (sc) SCCVII leg tumors in mice were irradiated with x-rays

James F. Hainfeld; F. Avraham Dilmanian; Zhong Zhong; Daniel N. Slatkin; John A. Kalef-Ezra; Henry M. Smilowitz

2010-01-01

374

Hematologic malignancies following external beam radiation therapy for localized prostate cancer  

Microsoft Academic Search

Ojha, Rohit P. Hematologic malignancies following external beam radiation therapy for localized prostate cancer. Doctor of Public Health (Epidemiology), December 2010, 88 pp., 6 tables, 2 illustrations, references, 96 titles.\\u000a \\u000aThe incidence of hematologic malignancies following external beam radiation therapy (EBRT) among prostate cancer patients has received limited attention despite evidence that radiation has a role in leukemogenesis and myelomagenesis.

Rohit Ojha

2010-01-01

375

Clinical experience with intensity modulated radiation therapy (IMRT) in prostate cancer  

Microsoft Academic Search

Purpose: To compare acute and late toxicities of high-dose radiation for prostate cancer delivered by either conventional three-dimensional conformal radiation therapy (3D-CRT) or intensity modulated radiation therapy (IMRT).Materials and methods: Between September 1992 and February 1998, 61 patients with clinical stage T1c- T3 prostate cancer were treated with 3D-CRT and 171 with IMRT to a prescribed dose of 81 Gy.

Michael J Zelefsky; Zvi Fuks; Laura Happersett; Henry J Lee; C. Clifton Ling; Chandra M Burman; Margie Hunt; Theresa Wolfe; E. S Venkatraman; Andrew Jackson; Mark Skwarchuk; Steven A Leibel

2000-01-01

376

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

SciTech Connect

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.

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

1986-08-01

377

[Radiation therapy for prostate cancer in the new S3 guideline. Part 2: postoperative radiation therapy and brachytherapy].  

PubMed

Postoperative adjuvant radiation therapy has achieved special significance based on the results of three randomized studies on stage pT3R1 prostate cancer which provided evidence for prolonged survival in comparison to the "wait and see" strategy. When PSA levels persist or increase after radical prostatectomy, irradiation represents an alternative. In this instance, salvage radiotherapy should be initiated as early as possible, most suitably when the PSA level is <0.5 ng/ml. Side effects of percutaneous radiotherapy using modern techniques are minimal in this stage; severe grade 3 or 4 late sequelae occur in <3% of cases. Low dose rate (LDR) brachytherapy as monotherapy is a primary treatment option for low-risk tumors. In patients with intermediate-risk tumors, data are controversial and cannot be assessed conclusively. LDR brachytherapy should not be administered in high-risk tumors. High dose rate (HDR) brachytherapy combined with percutaneous radiotherapy as an example of a typical dose escalation approach is a primary option for intermediate- and high-risk prostate cancer. Whether additional hormone therapy is needed with HDR brachytherapy is unclear. HDR monotherapy can only be recommended in the clinical trial setting. PMID:20180062

Martin, T; Wenz, F; Bhmer, D; Sedlmayer, F; Hinkelbein, W; Henkel, T O; Miller, K; Wiegel, T

2010-02-01

378

Transient enlargement of craniopharyngioma after radiation therapy: pattern of magnetic resonance imaging response following radiation.  

PubMed

Clinical experience suggests that craniopharyngiomas may temporarily increase in size after radiation therapy (RT). The study goal is to determine the incidence and natural history of this response in a cohort of patients managed at Children's Healthcare of Atlanta (CHOA) or Emory Healthcare (EHC). Between 08/1998 and 06/2009, 41 children and young adults were diagnosed with craniopharyngioma at CHOA and/or EHC. Of these, 21 received external-beam radiation and were included in our analysis. Serial magnetic resonance imaging (MRI) studies were evaluated volumetrically to assess response to RT. Median age at diagnosis was 8.2 years (range 3.2-23.5 years). Median radiation dose was 54.0 Gy using standard fractionation (1.8-2.0 Gy/day). With median follow-up of 41.3 months (range 7.2-121.8 months), actuarial local control and overall survival rates at 5 years were 78.7 % and 100 %, respectively. Of subjects, 52.4 % of subjects (11 of 21) were noted on serial MRI evaluation to have tumor enlargement (mostly cystic component) after radiation before eventual shrinkage without further intervention. For tumors that expanded, the median volume increase was 33.9 % (range 15.6-224.4 %). Median time to maximal tumor/cyst expansion was 1.5 months (range 1.0-5.0 months). Finally, nearly all patients (20 of 21) showed a measurable objective response to therapy by MRI regardless of ultimate disease control. Median time to maximal response post-radiation, as defined by MRI, was 9.5 months (range 3.5-39.9 months). In summary, RT is effective for managing craniopharyngioma. However, despite good ultimate responses, approximately 50 % of the patients show tumor/cyst expansion on MRI over the first few months post-radiation. Caution should be taken not to subject these patients to "salvage surgery" or cyst aspiration during this early time unless there are other overriding surgical indications. Understanding the natural history of this phenomenon could potentially help guide the management of these craniopharyngioma patients. PMID:22692563

Shi, Zheng; Esiashvili, Natia; Janss, Anna J; Mazewski, Claire M; MacDonald, Tobey J; Wrubel, David M; Brahma, Barunashish; Schwaibold, Frederick P; Marcus, Robert B; Crocker, Ian R; Shu, Hui-Kuo G

2012-06-13

379

Optimization of Adjuvant Radiation in Breast Conservation Therapy: Can We Minimize without Compromise?  

PubMed Central

Adjuvant breast radiation therapy after breast conservation surgery is recommended as it yields significant reduction in the risk of local recurrence, and confers a potential overall survival benefit. Although the standard breast radiation regimen has historically been delivered over 57 weeks; more novel, shorter courses of breast radiation are currently being employed, offering the advantage of more convenience and less time-commitment. Herein, we review the recent literature substantiating these abbreviated radiation treatment approaches and the methods of delivery thereof. In addition, we discuss imaged guided techniques currently being utilized to further refine the delivery of adjuvant breast radiation therapy.

Edwards-Bennett, Sophia M.; Correa, Candace R.; Harris, Eleanor E.

2011-01-01

380

Exceptionally high incidence of symptomatic grade 25 radiation pneumonitis after stereotactic radiation therapy for lung tumors  

Microsoft Academic Search

BACKGROUND: To determine the usefulness of dose volume histogram (DVH) factors for predicting the occurrence of radiation pneumonitis (RP) after application of stereotactic radiation therapy (SRT) for lung tumors, DVH factors were measured before irradiation. METHODS: From May 2004 to April 2006, 25 patients were treated with SRT at the University of Tokyo Hospital. Eighteen patients had primary lung cancer

Hideomi Yamashita; Keiichi Nakagawa; Naoki Nakamura; Hiroki Koyanagi; Masao Tago; Hiroshi Igaki; Kenshiro Shiraishi; Nakashi Sasano; Kuni Ohtomo

2007-01-01

381

Radiation therapy after breast augmentation or reconstruction in early or recurrent breast cancer  

Microsoft Academic Search

Fourteen patients whose augmented or reconstructed breasts were treated with radiation therapy were analyzed. Silicone gel implants were used in 13 patients and free-injected silicone in one patient. The total radiation dose ranged from 4400 to 6200 cGy using tangential photon fields or an en face electron field by megavoltage equipment. In several cases, electron boost radiation was added to

Janice Ryu; Joachim Yahalom; Brenda Shank; Ted A. Chaglassian; Beryl McCormick

1990-01-01

382

Advances in image-guided radiation therapythe role of PET-CT  

Microsoft Academic Search

In the era of image-guided radiation therapy (IGRT), the greatest challenge remains target delineation, as the opportunity to maximize cures while simultaneously decreasing radiation dose to the surrounding normal tissues is to be realized. Over the last 2 decades, technological advances in radiographic imaging, biochemistry, and molecular biology have played an increasing role in radiation treatment planning, delivery, and evaluation

Dwight E.. Heron; Ryan P. Smith; Regiane S. Andrade

2006-01-01

383

Image recording system characteristics for radiation therapy: portal localization and verification  

Microsoft Academic Search

Radiotherapy portal imaging is the process of producing images using a radiation treatment linear accelerator or cobalt 60 unit. Portal images are used to evaluate the position of the radiation treatment beam and placement of shielding blocks with respect to the patient's anatomy. This paper discusses types, characteristics and clinical use of radiation therapy portal imaging systems.

Arthur G. Haus; Robert E. Dickerson; Kenneth E. Huff; Terese M. Bogucki

1996-01-01

384

Carcinogenic effects of scattered dose associated with radiation therapy  

Microsoft Academic Search

Ionizing radiation has long been recognized as a weak carcinogen, and the risk of developing a radiation induced neoplasm after exposure to therapeutic radiation has been established. In the case of therapeutic radiation for treatment of existing malignancies, concomitant risk factors for second malignancies can confound the effect of radiation alone. This study presents a model for evaluating the isolated

Richard L. Cumberlin; Anatoly Dritschilo; Kenneth L. Mossman

1989-01-01

385

Radiation therapy for Bowen's disease of the skin  

SciTech Connect

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%), 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 distant cutaneous site. As of last follow-up, 32 patients (73%) were known to be alive. Median follow-up was 2.6 years (range, 0-11.8 years). All but 3 patients were disease-free at last follow-up, 1 of whom died with distant, but not local disease. The 5-year overall survival rate was 68%. Biologically effective dose was not associated with recurrence. The crude local control rate was 93%. There was a trend toward higher radiation doses for smaller pretreatment tumor and field sizes. The BED did not correlate with Grade 4 toxicity; however, the three cases of Grade 4 toxicity occurred in patients treated with hypofractionated regimens (dose per fraction >4 Gy) for extremity lesions. Conclusions: Radiation therapy is an effective treatment option for Bowen's disease of the skin. Local recurrences seem to be equally low in patients treated with high- and low-dose regimens. Avoiding hypofractionated regimens (dose per fraction >4 Gy) in extremity locations might reduce the risk of Grade 4 toxicity.

Lukas VanderSpek, Lauren A. [Department of Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario (Canada)]. E-mail: lauren.vanderspek@lrcc.on.ca; Pond, Gregory R. [Department of Clinical Study Co-ordination and Biostatistics, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario (Canada); Wells, Woodrow [Department of Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario (Canada); Tsang, Richard W. [Department of Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario (Canada)

2005-10-01

386

Real-time dosimetry in external beam radiation therapy.  

PubMed

With growing complexity in radiotherapy treatment delivery, it has become mandatory to check each and every treatment plan before implementing clinically. This process is currently administered by an independent secondary check of all treatment parameters and as a pre-treatment quality assurance (QA) check for intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy treatment plans. Although pre-treatment IMRT QA is aimed to ensure the correct dose is delivered to the patient, it does not necessarily predict the clinically relevant patient dose errors. During radiotherapy, treatment uncertainties can affect tumor control and may increase complications to surrounding normal tissues. To combat this, image guided radiotherapy is employed to help ensure the plan conditions are mimicked on the treatment machine. However, it does not provide information on actual delivered dose to the tumor volume. Knowledge of actual dose delivered during treatment aid in confirming the prescribed dose and also to replan/reassess the treatment in situations where the planned dose is not delivered as expected by the treating physician. Major accidents in radiotherapy would have been averted if real time dosimetry is incorporated as part of the routine radiotherapy procedure. Of late real-time dosimetry is becoming popular with complex treatments in radiotherapy. Real-time dosimetry can be either in the form of point doses or planar doses or projected on to a 3D image dataset to obtain volumetric dose. They either provide entrance dose or exit dose or dose inside the natural cavities of a patient. In external beam radiotherapy, there are four different established platforms whereby the delivered dose information can be obtained: (1) Collimator; (2) Patient; (3) Couch; and (4) Electronic Portal Imaging Device. Current real-time dosimetric techniques available in radiotherapy have their own advantages and disadvantages and a combination of one or more of these methods provide vital information about the actual dose delivered to radiotherapy patients. PMID:24179630

Prabhakar, Ramachandran

2013-10-28

387

Real-time dosimetry in external beam radiation therapy  

PubMed Central

With growing complexity in radiotherapy treatment delivery, it has become mandatory to check each and every treatment plan before implementing clinically. This process is currently administered by an independent secondary check of all treatment parameters and as a pre-treatment quality assurance (QA) check for intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy treatment plans. Although pre-treatment IMRT QA is aimed to ensure the correct dose is delivered to the patient, it does not necessarily predict the clinically relevant patient dose errors. During radiotherapy, treatment uncertainties can affect tumor control and may increase complications to surrounding normal tissues. To combat this, image guided radiotherapy is employed to help ensure the plan conditions are mimicked on the treatment machine. However, it does not provide information on actual delivered dose to the tumor volume. Knowledge of actual dose delivered during treatment aid in confirming the prescribed dose and also to replan/reassess the treatment in situations where the planned dose is not delivered as expected by the treating physician. Major accidents in radiotherapy would have been averted if real time dosimetry is incorporated as part of the routine radiotherapy procedure. Of late real-time dosimetry is becoming popular with complex treatments in radiotherapy. Real-time dosimetry can be either in the form of point doses or planar doses or projected on to a 3D image dataset to obtain volumetric dose. They either provide entrance dose or exit dose or dose inside the natural cavities of a patient. In external beam radiotherapy, there are four different established platforms whereby the delivered dose information can be obtained: (1) Collimator; (2) Patient; (3) Couch; and (4) Electronic Portal Imaging Device. Current real-time dosimetric techniques available in radiotherapy have their own advantages and disadvantages and a combination of one or more of these methods provide vital information about the actual dose delivered to radiotherapy patients.

Prabhakar, Ramachandran

2013-01-01

388

Proposing the lymphatic target volume for elective radiation therapy for pancreatic cancer: a pooled analysis of clinical evidence  

Microsoft Academic Search

BACKGROUND: Radiation therapy is an important cancer treatment modality in both adjuvant and definitive setting, however, the use of radiation therapy for elective treatment of regional lymph nodes is controversial for pancreatic cancer. No consensus on proper selection and delineation of subclinical lymph nodal areas in adjuvant or definitive radiation therapy has been suggested either conclusively or proposed for further

Wenjie Sun; Cheng N Leong; Zhen Zhang; Jiade J Lu

2010-01-01

389

Acute myelogenous leukemia following radiation therapy and chemotherapy for osteogenic sarcoma  

SciTech Connect

Patients receiving ionizing radiation therapy or cytotoxic chemotherapy are at increased risk of developing acute myelogenous leukemia. Ten cases of therapy-linked myelogenous leukemia have been reported in patients with sarcoma, and the authors report here the first case in a patient who received combined-modality therapy for treatment of an osteogenic sarcoma. As treatment for this disease becomes more intensive and survival improves, the incidence of leukemia following therapy for osteogenic sarcoma may increase.

Jacobs, A.D.; Gale, R.P.

1984-06-01

390

A 3D digitzation system for conventional radiation therapy.  

PubMed

While the majority of patients receiving external beam radiation therapy treatment are planned by CT simulation, a significant number of them are still planned using conventional simulators for various reasons. The information-collection process in a conventional simulation is often fragmented and done with primitive tools. For example, in many institutions body contours are still acquired using solder wires and tracing paper, a time-consuming and error-prone procedure. We have developed a 3D digitization system to assist the information-acquisition process at conventional simulations. The system consists of an infrared camera assembly, a wireless digitizer probe, and Windows-based software. The system can provide 3D coordinates of any points in space accessible by the probe with submillimeter accuracy. It can be used to capture body contours, to record the coordinates of portal points, and to take various measurements for dose calculations as well as for patient setup. The software can display all the captured data together with the planned treatment fields, providing a comprehensive geometric verification of the treatment configuration. The system can also transfer all the information to dose planning programs in DICOM-RT format, providing an integrated information flow from simulation to dose planning. PMID:16143795

Lu, Hsiao-Ming

2005-08-12

391

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System  

SciTech Connect

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 Millipore 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.

Eigler, N.; Whiting, J.; Chernomorsky, A.; Jackson, J.; Knapp, F.F., Jr.; Litvack, F.

1998-01-16

392

Intensity-Modulated Radiation Therapy in Childhood Ependymoma  

SciTech Connect

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% {+-} 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.

Schroeder, Thomas M. [Department of Radiation Oncology, University of New Mexico Cancer Center, University of New Mexico, Albuquerque, NM (United States); Chintagumpala, Murali; Okcu, M. Fatih [Division of Pediatric Hematology-Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX (United States); Division of Pediatric Hematology-Oncology, Department of Pediatrics, Texas Children's Hospital, Houston, TX (United States); Chiu, J. Kam; Teh, Bin S. [Department of Radiation Oncology, Methodist Hospital, Houston, TX (United States); Division of Radiation Oncology, Department of Radiology, Baylor College of Medicine, Houston, TX (United States); Woo, Shiao Y. [Department of Radiation Oncology, M.D. Anderson Cancer Center, Houston, TX (United States); Paulino, Arnold C. [Department of Radiation Oncology, Methodist Hospital, Houston, TX (United States); Division of Radiation Oncology, Department of Radiology, Baylor College of Medicine, Houston, TX (United States)], E-mail: apaulino@tmhs.org

2008-07-15

393

Extracranial radiosurgery (stereotactic body radiation therapy) for oligometastases.  

PubMed

Extracranial radiosurgery, also known as stereotactic body radiation therapy (SBRT), is an increasingly used method of treatment of limited cancer metastases located in a variety of organs/sites including the spine, lungs, liver, and other areas in the abdomen and pelvis. The techniques used to perform SBRT were initially modeled after intracranial radiosurgery, although considerable evolution in technique and conduct has occurred for extracranial applications. Unlike intracranial radiosurgery, SBRT requires characterization and accounting for inherent organ movement including breathing motion. Potent dose hypofractionation schedules have been used with SBRT such that the treatment is generally both ablative and convenient. Because the treatment is severely damaging to tissues within and about the target, the volume of adjacent normal tissue must be strictly minimized to avoid toxic late effects. Outcomes in various sites show very high rates of local control with toxicity mostly related to tubular tissues like the airways and bowels. With proper conduct though, SBRT can be an extremely effective treatment option for oligometastases. PMID:16564443

Kavanagh, Brian D; McGarry, Ronald C; Timmerman, Robert D

2006-04-01

394

Registration-based initialization during radiation therapy planning  

NASA Astrophysics Data System (ADS)

An established challenge in the field of image analysis has been the registration of images having a large initial misalignment. For example in chemo and Radiation Therapy Planning (RTP), there is often a need to register an image delineating a specific anatomy (usually in the surgery position) with that of a whole body image (obtained preoperatively). In such a scenario, there is room for a large misalignment between the two images that are required to be aligned. Large misalignments are traditionally handled in two ways: 1) Semi-automatically with a user initialization or 2) With the help of the origin fields in the image header. The first approach is user dependant and the second method can be used only if the two images are obtained from the same scanner with consistent origins. Our methodology extends a typical registration framework by selecting components that are capable of searching a large parameter space without settling on local optima. We have used an optimizer that is based on an Evolutionary Scheme along with an information theory based similarity metric that can address these needs. The attempt in this study is to convert a large misalignment problem to a small misalignment problem that can then be handled using application specific registration algorithms. Further improvements along local areas can be obtained by subjecting the image to a non-rigid transformation. We have successfully registered the following pairs of images without any user initialization: CTAC - simCT (neuro, lungs); MRPET/ CT (neuro, liver); T2-SPGR (neuro).

Gopalakrishnan, Girish; Mullick, Rakesh

2007-03-01

395

A radiation-controlled molecular switch for use in gene therapy of cancer  

Microsoft Academic Search

Ionising radiation induces the expression of a number of radiation-responsive genes and there is current interest in exploiting this to regulate the expression of exogenous therapeutic genes in gene therapy strategies for cancer. However, the radiation-responsive promoters used in these approaches are often associated with low and transient levels of therapeutic gene expression. We describe here a novel radiation-triggered molecular

SD Scott; B Marples; JH Hendry; LS Lashford; MJ Embleton; A Howell; GP Margison

2000-01-01

396

Impact of machines on plan quality: volumetric modulated arc therapy and intensity modulated radiation therapy.  

PubMed

PURPOSE: To evaluate the impact of different machines on plan quality using both intensity modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) techniques. MATERIALS AND METHODS: Eight patients with squamous cell carcinoma of the oropharynx were selected at random. Plans were computed for IMRT and VMAT Smart Arc, using Pinnacle TPS for an Elekta (IMRT-E, VMAT-E) and Varian linac (IMRT-V, VMAT-V). A three-dose level prescription was used to deliver 70, 63 and 58.1Gy to regions of macroscopic, microscopic high- and low-risk disease, respectively. All doses were given in 35 fractions. Comparisons were performed on dose-volume histogram data, monitor units (MU), and delivery time. RESULTS: VMAT-E plans resulted slightly MU efficient (-24% p<0.05) compared to VMAT-V while IMRT-V shortened delivery time (-19% p<0.05) compared to IMRT-E. All the delivery techniques resulted in equivalent target coverage in terms of D98% and D2%. For VMAT technique, a significant improvement of 7% in homogeneity index (HI) for PTV58.1 was observed for Varian machine. A slight improvement in OARs sparing was observed with Elekta machine both for IMRT and VMAT techniques. CONCLUSION: Similar plan quality was observed for Elekta and Varian linacs, significant differences were observed in delivery efficiency, as MU number and delivery times, in favor of Elekta and Varian, respectively. PMID:23645162

Clemente, S; Cozzolino, M; Oliviero, C; Fiorentino, A; Chiumento, C; Fusco, V

2013-05-01

397

A Prospective Study of Conformal Radiation Therapy for Pediatric Ependymoma  

PubMed Central

Background Successful therapy for ependymoma includes aggressive surgical intervention and radiation therapy administered using methods which minimize the risk of side effects. We extended this treatment approach to include children under the age of 3 years. Methods Between July 1997 and 2007, 153 pediatric patients (median age 29 years, range 09229 years) with localized ependymoma received conformal radiation therapy after definitive surgery. Doses of 594 (n=131) or 540 Gy (n=22) were prescribed to a 10mm clinical target volume margin surrounding the post-operative residual tumor and/or tumor bed. The patients had the following characteristics: anaplastic ependymoma (n=85), infratentorial location (n=122), prior chemotherapy (n=35) and extent of resection (gross-total=125, near-total=17, subtotal=11). Disease control, patterns of failure and complications were recorded for patients followed through 10 years. Findings With a median follow-up of 53 years (range 04 to 104 years), death was recorded in 23 patients and tumor progression in 36, including local (n=14), distant (n=15) and combined failure (n=7). Tumor grade predicted overall (OS) and event-free (EFS) survival and distant failure. Extent of resection predicted OS, EFS and local failure. Race predicted OS. The 7 year local control, event-free and overall survival were 837% (95% CI: 739935%), 691% (95% CI: 569813%) and 810% (95% CI: 710910%), respectively. The cumulative incidence of local and distance failure were 163% (95% CI: 96230%) and 1148% (95% CI: 59171%), respectively. Considering only those patients treated with immediate post-operative CRT (without delay or chemotherapy) the 7 year OS, EFS and CI of local and distant failure were 850% (95% CI: 742958%), 769% (95% CI: 634904%), 1259% (95% CI: 51201%)and 856% (95% CI: 28143%), respectively. The incidence of secondary malignant brain tumor at 7 years was 23% (95% CI: 056%) and brainstem necrosis 16% (95% CI: 040%). Interpretation This study provides new disease control benchmarks and a unifying approach for the treatment of ependymoma that should include surgery with the aim of gross-total resection and conformal, high-dose, post-operative irradiation even for the youngest children. Future trials might consider treatment stratification based on gender and age as female patients are more likely to be long-term survivors and younger patients have higher rates of failure.

Merchant, Thomas E.; Li, Chenghong; Xiong, Xiaoping; Kun, Larry E.; Boop, Frederic A.; Sanford, Robert A.

2013-01-01

398

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

SciTech Connect

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 rotational 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 confidence was within {+-} 4.5 mm coordinates shifting. IGRT using XVIcbs is critical to IMRT for prostate and H and N, especially SRT, SRS, and SBRT. To optimize this modality of IGRT, a vigilant QA program is indispensable. Prostate IGRT reveals treatment accuracy as subject to coordinates' adjustments; otherwise a 4.5-mm margin is required to allow for full dose coverage of the clinical target volume, notwithstanding toxicity to normal tissues.

Tsai, Jen-San, E-mail: jen-san.tsai@verizon.net [Department of Radiation Oncology, Temple University Hospital, Philadelphia, PA (United States); Micaily, Bizhan; Miyamoto, Curtis [Department of Radiation Oncology, Temple University Hospital, Philadelphia, PA (United States)

2012-10-01

399

Adjuvant and definitive radiation therapy for primary carcinoma of the vagina using brachytherapy and external beam radiation therapy  

PubMed Central

Purpose To report the outcomes of patients receiving vaginal brachytherapy and/or external beam radiation therapy (EBRT) for primary vaginal cancer. Material and methods Between 1983 and 2009, 63 patients received brachytherapy and/or EBRT for primary tumors of the vagina at a single tertiary center. Patient data was collected via chart review. The Kaplan-Meier method was used to calculate actuarial pelvic local control (LC), disease-free survival (DFS), overall survival (OS), and severe late toxicity rates. Acute and late toxicities were scored according to the Common Terminology Criteria for Adverse Events version 3 (CTCAE v3.0). Results Median follow up was 44.2 months. Patients with early stage disease (stages I and II) had significantly improved 5-year OS when compared to patients with locally advanced disease (stages III and IVA) (73.3 vs. 34.4%, p = 0.032). Patients with greater than 1/3 vaginal involvement had significantly worse prognosis than patients with tumors involving 1/3 or less of the vagina, with the later having superior DFS (84.0 vs. 52.4%, p = 0.007) and LC (86.9 vs. 60.4%, p = 0.018) at 5-years. Age, histology, and brachytherapy technique did not impact treatment outcomes. The 5-year actuarial grade 3 or higher toxicity rate was 23.1% (95% CI: 10.6-35.6%). Concurrent chemotherapy had no impact on outcomes or toxicity in this analysis. Conclusions Success of treatment for vaginal cancer depends primarily on disease stage, but other contributing factors such as extent of vaginal involvement and tumor location significantly impact outcomes. Treatment of vaginal cancer with primary radiotherapy yields acceptable results with reasonable toxicity rates. Management of this rare malignancy requires a multidisciplinary approach to appropriately optimize therapy.

Anderson, Bethany; Geye, Heather; Das, Rupak; Straub, Margaret; Bradley, Kristin

2013-01-01

400

Hematopoietic toxicity of regional radiation therapy. Correlations for combined modality therapy with systemic chemotherapy  

SciTech Connect

Using circulating granulocyte-monocyte precursor colony-forming units in culture (CFUc) numbers as a probe along with standard blood count (CBC), the authors have quantitatively examined the hematopoietic toxicity of conventionally fractionated radiation therapy (RT) when combined with concurrent systemic chemotherapy or when used alone. Among 20 patients with limited stage small cell lung cancer receiving systemic chemotherapy with cyclophosphamide, CCNU, and methotrexate, the addition of involved field chest RT resulted in increased hematopoietic toxicity as judged by increased need for platelet transfusion (P less than 0.05) and decreased frequency of measurable CFUc (P less than 0.04). Among 22 patients receiving regional radiotherapy alone consistent hematopoietic toxicity was also observed. This toxicity, although generally of only mild to moderate clinical significance, was detected earlier and to a greater degree in patients who required radiation to larger treatment volumes, who had significant amounts of bone marrow in the port, and who had a high percentage of cardiac output flowing through the port. These data suggest that the hematopoietic toxicity of regional radiotherapy may be additive to that of concurrent systemic chemotherapy and may occur more promptly and to a greater degree when treatment volumes are larger or incorporate increased amounts of marrow volume or cardiac output.

Abrams, R.A.; Lichter, A.S.; Bromer, R.H.; Minna, J.D.; Cohen, M.H.; Deisseroth, A.B.

1985-04-01

401

The effect of stochastic fluctuation in radiation dose-rate on cell survival following fractionated radiation therapy  

NASA Astrophysics Data System (ADS)

In radiobiological models, it is often assumed that the radiation dose rate remains constant during the course of radiation delivery. However, instantaneous radiation dose rate undergoes random (stochastic) temporal fluctuation. The effect of stochastic dose rate in fractionated radiation therapy is unknown and there has been no analytical formulation of stochastic dose-rate fluctuation effect in fractionated radiation therapy which we endeavor to pursue here. We have obtained the quantitative expression of cellular survival fraction considering stochastic temporal fluctuation or noise in dose rate. We have shown that the constant dose-rate approximation overestimates the survival fraction compared to that under stochastic dose rate in a fractionated radiation therapy situation and this overestimation effect increases appreciably with the increase in the fluctuation level in dose rate. However, for a given level of fluctuation in dose rate, overestimation of survival fraction also depends on the value of cellular radiation sensitivity parameter ? and the repair rate of DNA lesion. This overestimation effect is higher for the cells which have a higher value of ? parameter or have a lower repair rate. Our study draws attention to stochastic temporal fluctuation in the radiation dose rate and its potential contribution to cell survival following fractionated radiotherapy.

Paul, Subhadip; Roy, Prasun K.

2012-03-01

402

Non-invasive detection of vulnerable coronary plaque  

PubMed Central

Critical coronary stenoses have been shown to contribute to only a minority of acute coronary syndromes and sudden cardiac death. Autopsy studies have identified a subgroup of high-risk patients with disrupted vulnerable plaque and modest stenosis. Consequently, a clinical need exists to develop methods to identify these plaques prospectively before disruption and clinical expression of disease. Recent advances in invasive and non-invasive imaging techniques have shown the potential to identify these high-risk plaques. Non-invasive imaging with magnetic resonance imaging, computed tomography and positron emission tomography holds the potential to differentiate between low- and high-risk plaques. There have been significant technological advances in non-invasive imaging modalities, and the aim is to achieve a diagnostic sensitivity for these technologies similar to that of the invasive modalities. Molecular imaging with the use of novel targeted nanoparticles may help in detecting high-risk plaques that will ultimately cause acute myocardial infarction. Moreover, nanoparticle-based imaging may even provide non-invasive treatments for these plaques. However, at present none of these imaging modalities are able to detect vulnerable plaque nor have they been shown to definitively predict outcome. Further trials are needed to provide more information regarding the natural history of high-risk but non-flow-limiting plaque to establish patient specific targeted therapy and to refine plaque stabilizing strategies in the future.

Sharif, Faisal; Lohan, Derek G; Wijns, William

2011-01-01

403

Three-dimensional conformal therapy versus standard radiation therapy in localized carcinoma of prostate: an update.  

PubMed

This study updates technical principles and results of 3-dimensional conformal radiation therapy (3D-CRT) in localized carcinoma of the prostate. Between January 1992 and December 1999, 312 patients were treated with 3D-CRT and 135 patients were treated with bilateral arcs standard radiation therapy (SRT) alone for clinical stage T1b-c or T2 histologically confirmed prostate cancer. None of these patients received hormonal therapy. Mean follow-up for patients in the 3D-CRT group was 3.2 years (range, 2-5.9 years) and for SRT patients, 4.7 years (range, 4-7 years). For 3D-CRT, 7 intersecting fields were used (cerrobend blocking or multileaf collimation) to deliver 68-74 Gy to the prostate. Standard radiation therapy consisted of bilateral 120 degree rotational arcs, with portals using 2-cm margins around the prostate to deliver 68-70 Gy to the prostate. The criterion for chemical disease-free survival was a postirradiation prostate-specific antigen (PSA) value following the American Society for Therapeutic Radiology and Oncology guidelines. Symptoms during treatment were quantitated weekly, and late effects were assessed every 4-6 months. Dose-volume histograms showed a two-thirds reduction with 3D-CRT in normal bladder or rectum receiving > or = 70 Gy with 3D-CRT. Higher 5-year chemical disease-free survival was observed with 3D-CRT (75%; for T1b-c and 79%; for T2 tumors) compared with SRT (61% and 65%, P = 0.01 and P = 0.12, respectively). There was no statistically significant difference in chemical disease-free survival in patients with Gleason score of < or = 4 (P = 0.85), but, with Gleason score of 5-7, the 5-year survival rates were 83% with 3D-CRT and 59% with SRT (P < or = 0.01). In 245 patients with pretreatment PSA of < or = 10 ng/mL treated with 3D-CRT, the chemical disease-free rate was 80% versus 72% in 98 patients treated with SRT (P = 0.21). In patients with PSA of 10.1-20 ng/mL, the chemical disease-free survival rate for 50 patients treated with 3D-CRT was 71% compared with 43% for 20 patients treated with SRT (P = 0.02). The corresponding values were 59% and 16%, respectively, for patients with PSA levels > 20 ng/mL (P = 0.09). On multivariate analysis, the most important prognostic factors for chemical failure were pretreatment PSA (P = 0.004), nadir PSA (P = 0.001), and 3D-CRT technique (P = 0.012). Moderate dysuria was reported by 2%-5% of patients treated with 3D-CRT in contrast to 6%-9% of patients treated with SRT. The incidence of moderate loose stools or diarrhea, usually after the fourth week of treatment, was 3%-5% in the 3D-CRT patients and 8%-19% in the SRT group. Late intestinal grade 2 morbidity (proctitis or rectal bleeding) was 1% in the 3D-CRT group in contrast to 7% in SRT patients. The 3D-CRT spares more normal tissues, yields higher chemical disease-free survival, and results in less treatment morbidity than SRT in treatment of stage T1-T2 prostate cancer. Follow-up at > or = 10 years is needed to confirm these observations. PMID:15046700

Perez, Carlos A; Michalski, Jeff M; Mansur, David; Lockett, Mary Ann

2002-09-01

404

[Cervical cancer--phase III studies of radiation therapy combined modality].  

PubMed

The number of patients with cervical cancer has been constantly reduced but it remains a leading cause of death among gynecologic malignancies in Japan. In 1990, 5,793 patients with cervical cancer were registered and 1,892 cases (32.7%) were stage 0, 2,074 cases (35.8%) were stage I, 991 cases (17.1%) were stage II, 659 cases (11.4%) were stage III and 172 cases (3.0%) were stage IV. Among these patients, about 40% were treated with radiation therapy alone or combined with radiation therapy. The five-year survival rates of stage I, II, III, and IV patients were 83.4%, 65.3%, 40.3% and 13.1%, respectively. Phase III studies have been conducted to compare surgical treatment and radiation therapy, and it is clarified that radiation therapy is equivalent to surgical therapy in young healthy patients with an early-stage tumor, while combined radiation therapy followed by surgery did not improve results over radiation alone. It is thus justified to offer postoperative irradiation to selected patients who have high-risk factors in the surgical specimen. Effects of chemotherapy were also compared to radiation therapy. Multiagent chemotherapy such as bleomycin, vincristine, mitomycin C, and cisplatin or bleomycin, ifosphamide and cisplatin are standard regimens for cervical cancer. However, because the toxicity of chemotherapy along with radiation therapy is much higher than that of radiation alone, there is a need to develop an adequate adjuvant chemotherapy regimen for cervical cancer. Other ongoing trials are also discussed. PMID:7880106

Ochiai, K

1995-02-01

405

Polarity Therapy for Cancer-Related Fatigue in Patients With Breast Cancer Receiving Radiation Therapy: A Randomized Controlled Pilot Study  

PubMed Central

Background Cancer-related fatigue (CRF) is the most frequently reported side effect of cancer and its treatment. In previous research, Polarity Therapy (PT), an energy therapy, was shown to reduce CRF in patients receiving radiation. This study reports on a small randomized clinical trial designed to collect preliminary data on the efficacy of PT compared with an active control (massage) and passive control (standard care) for CRF among cancer patients receiving radiation therapy. Methods Forty-five women undergoing radiation therapy for breast cancer were randomized to I of 3 weekly treatment conditions. Patients received standard clinical care, 3 modified massages, or 3 PT treatments. CRF and healthrelated quality of life (HRQL) were assessed during baseline and the 3 intervention weeks. Results TResults show CRF ratings were reduced after PT. The effect sizes for PT versus modified massage and versus standard care were small when using the primary measure of CRF (Brief Fatigue Inventory) and large when using the secondary measure of CRF (Daily CRF Diaries).The effect size was medium when assessing the benefit of PT on maintaining HRQL compared with standard care with very little difference between the PT and modified massage conditions. Patients feedback showed that both the modified massage and PT treatments were deemed useful by radiation patients. Conclusion. The present pilot randomized clinical trial supports previous experimental research showing that PT, a noninvasive and gentle energy therapy, may be effective in controlling CRF. Further confirmatory studies as well as investigations of the possible mechanisms of PT are warranted.

Mustian, Karen M.; Roscoe, Joseph A.; Palesh, Oxana G.; Sprod, Lisa K.; Heckler, Charles E.; Peppone, Luke J.; Usuki, Kenneth Y.; Ling, Marilyn N.; Brasacchio, Ralph A.; Morrow, Gary R.

2011-01-01

406

Combination Nonviral Interleukin 2 Gene Therapy and External-Beam Radiation Therapy for Head and Neck Cancer  

Microsoft Academic Search

Objectives: To demonstrate that the combination of nonviral murine interleukin 2 (mIL-2) gene therapy and external-beam radiation therapy (XRT) have an en- hanced therapeutic effect for the treatment of head and neck squamous cell carcinoma (HNSCC) in an ortho- topic murine model and to elucidate the mechanism of action. Methods: Randomized, controlled studies in the mu- rine orthotopic model of

David Bray; Shu-Zhen Yu; Hilary Koprowski; Juong Rhee; Sanjeev Kumar; Federica Pericle; Mohan Suntharalingam; David A. Van Echo; Daqing Li; Bert W. O'Malley

2003-01-01

407

Gold nanoparticles enhance the radiation therapy of a murine squamous cell carcinoma  

NASA Astrophysics Data System (ADS)

The purpose of this study is to test the hypothesis that gold nanoparticle (AuNP, nanogold)-enhanced radiation therapy (nanogold radiation therapy, NRT) is efficacious when treating the radiation resistant and highly aggressive mouse head and neck squamous cell carcinoma model, SCCVII, and to identify parameters influencing the efficacy of NRT. Subcutaneous (sc) SCCVII leg tumors in mice were irradiated with x-rays at the Brookhaven National Laboratory (BNL) National Synchrotron Light Source (NSLS) with and without prior intravenous (iv) administration of AuNPs. Variables studied included radiation dose, beam energy, temporal fractionation and hyperthermia. AuNP-mediated NRT was shown to be effective for the sc SCCVII model. AuNPs were more effective at 42 Gy than at 30 Gy (both at 68 keV median beam energy) compared to controls without gold. Similarly, at 157 keV median beam energy, 50.6 Gy NRT was more effective than 44 Gy NRT. At the same radiation dose (~42 Gy), 68 keV was more effective than 157 keV. Hyperthermia and radiation therapy (RT) were synergistic and AuNPs enhanced this synergy, thereby further reducing TCD50 s (tumor control dose 50%) and increasing long-term survivals. It is concluded that gold nanoparticles enhance the radiation therapy of a radioresistant mouse squamous cell carcinoma. The data show that radiation dose, energy and hyperthermia influence efficacy and better define the potential utility of gold nanoparticles for cancer x-ray therapy.

Hainfeld, James F.; Avraham Dilmanian, F.; Zhong, Zhong; Slatkin, Daniel N.; Kalef-Ezra, John A.; Smilowitz, Henry M.

2010-06-01

408

The tolerance of skin grafts to postoperative radiation therapy in patients with soft-tissue sarcoma  

SciTech Connect

During the last ten years at the National Cancer Institute, 11 patients have received 12 courses of postoperative adjuvant radiation therapy to skin grafts used for wound closure after the resection of soft-tissue sarcomas. The intervals between grafting and the initiation of radiation ranged between 3 and 20 weeks, and 4 patients received chemotherapy at the same time as their radiation. Ten of the 12 irradiated grafts remained intact after the completion of therapy. One graft had several small persistently ulcerated areas that required no further surgical treatment, and one graft required a musculocutaneous flap for reconstruction of a persistent large ulcer. Acute radiation effects on the grafted skin sometimes developed at slightly lower doses than usually seen with normal skin, but these acute effects necessitated a break in therapy on only five occasions. Concurrent chemotherapy and a relatively short interval between grafting and the initiation of radiation seemed to contribute to more severe radiation reactions. This experience indicates that postoperative adjuvant radiation therapy can be delivered to skin grafted areas without undue fear of complications, especially if the graft is allowed to heal adequately prior to initiating therapy and if chemotherapy is not given in conjunction with radiation.

Lawrence, W.T.; Zabell, A.; McDonald, H.D. (National Cancer Institute, Bethesda, MD (USA))

1986-03-01

409

Phase II Radiation Therapy Oncology Group trial of conventional radiation therapy followed by treatment with recombinant interferon-{beta} for supratentorial glioblastoma: Results of RTOG 9710  

SciTech Connect

Purpose: The aim of this study was to determine whether recombinant human interferon {beta}-1a (rhIFN-{beta}), when given after radiation therapy, improves survival in glioblastoma. Methods and Materials: After surgery, 109 patients with newly diagnosed supratentorial glioblastoma were enrolled and treated with radiation therapy (60 Gy). A total of 55 patients remained stable after radiation and were treated with rhIFN-{beta} (6 MU/day i.m., 3 times/week). Outcomes were compared with Radiation Therapy Oncology Group glioma historical database. Results: RhIFN-{beta} was well tolerated, with 1 Grade 4 toxicity and 8 other patients experiencing Grade 3 toxicity. Median survival time (MST) of the 55 rhIFN-{beta}-treated patients was 13.4 months. MST for the 34 rhIFN-{beta}-treated in RPA Classes III and IV was 16.9 vs. 12.4 months for historical controls (hazard ratio [HR] = 1.27, 95% confidence interval [CI] = 0.89-1.81). There was also a trend toward improved survival across all RPA Classes comparing the 55 rhIFN-{beta} treated patients and 1,658 historical controls (HR = 1.24, 95% CI = 0.94-1.63). The high rate of early failures (54/109) after radiation and before initiation of rhIFN-{beta} was likely caused by stricter interpretation of early radiographic changes in the current study. Matched-pair and intent-to-treat analyses performed to try to address this bias showed no difference in survival between study patients and controls. Conclusion: RhIFN-{beta} given after conventional radiation therapy was well tolerated, with a trend toward survival benefit in patients who remained stable after radiation therapy. These data suggest that rhIFN-{beta} warrants further evaluation in additional studies, possibly in combination with current temozolomide-based regimens.

Colman, Howard [Department of Neuro-Oncology, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States) and Department of Brain Tumor Center, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States)]. E-mail: hcolman@mdanderson.org; Berkey, Brian A. [Statistics Department, Radiation Therapy Oncology Group Headquarters, Philadelphia, PA (United States); Maor, Moshe H. [Department of Radiation Oncology, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States); Department of Brain Tumor Center, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States); Groves, Morris D. [Department of Neuro-Oncology, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States); Department of Brain Tumor Center, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States); Schultz, Christopher J. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Vermeulen, Sandra [Swedish Cancer Institute-Department of Radiation Oncology/Northwest Hospital Gamma Knife Center, Seattle, WA (United States); Nelson, Diana F. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Mehta, Minesh P. [Department of Human Oncology, University of Wisconsin Medical School, Madison, WI (United States); Yung, W.K. Alfred [Department of Neuro-Oncology, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States); Department of Brain Tumor Center, University of Texas-M.D. Anderson Cancer Center, Houston, TX (United States)

2006-11-01

410

Controlling beam complexity in intensity-modulated radiation therapy  

NASA Astrophysics Data System (ADS)

External beam intensity modulated radiation therapy (IMRT) is a technique in which the spatial intensity of radiation from each beam direction can be modulated to provide superior conformality of dose to a tumor volume while sparing important normal tissues. A fundamental and potentially limiting feature of IMRT is the highly complex fields that can be created through inverse plan optimization. Highly modulated treatments are a large departure from conventional radiotherapy methods, are difficult to deliver accurately and efficiently, and can result in an undesirable increase in leakage dose being delivered to the patient. Longer deliveries may also increase the chance for patient motion during treatment and could potentially reduce the probability of controlling some tumors. The large intensity fluctuations observed in IMRT beams are often a result of the degeneracy of the optimization problem, and the types of optimization method and cost function used. This work demonstrates that beam complexity is a result of these two issues, and is dependent on the placement of dose evaluation points in the target and normal tissues. This research shows that (i) optimizing surfaces instead of discrete beamlet intensities to represent the beam can reduce the degrees of freedom in IMRT and results in much smoother beams at the expense of a slight increase in normal tissues, (ii) maximum beamlet intensity restrictions are useful for improved delivery efficiency, but may restrict the optimizer at low limits, and (iii) modulation penalties can be incorporated into the cost function to promote plan smoothness without sacrificing plan quality. Penalizing the overall plan modulation is an effective way to reduce modulation, but it falsely penalizes the desirable beam modulation as well as the undesirable modulation. To address this problem, diffusion principles are used to develop a spatially adaptive smoothing method that only penalizes the unnecessary beam modulation and can be used without degrading plan quality. This method is customizable to a variety of treatment scenarios. The clinical impact of reducing beam complexity is significant, as it can result in an improvement in delivery accuracy and efficiency, quicker optimization times, and increased robustness to point sampling and geometric uncertainty.

Matuszak, Martha Marie

411

Dose as a function of liver volume and planning target volume in helical tomotherapy, intensity-modulated radiation therapybased stereotactic body radiation therapy for hepatic metastasis  

Microsoft Academic Search

Purpose: Stereotactic body radiation therapy (SBRT) has been shown to be an effective, well-tolerated treatment for local control of tumors metastatic to the liver. Multi-institutional Phase II trials are examining 60 Gy in 3 fractions delivered by linac-based, 3D-conformal IMRT. HiArt Helical TomoTherapy is a treatment unit that delivers co-planar helical IMRT that is capable of image-guided SBRT. We hypothesized

Joseph M. Baisden; Andrew G. Reish; Ke Sheng; James M. Larner; Brian D. Kavanagh; Paul W.. Read

2006-01-01

412

The Vulnerable Plaque: the Real Villain in Acute Coronary Syndromes  

PubMed Central

The term "vulnerable plaque" refers to a vascular lesion that is prone to rupture and may result in life-threatening events which include myocardial infarction. It consists of thin-cap fibroatheroma and a large lipid core which is highly thrombogenic. Acute coronary syndromes often result from rupture of vulnerable plaques which frequently are only moderately stenosed and not visible by conventional angiography. Several invasive and non-invasive strategies have been developed to assess the burden of vulnerable plaques. Intravascular ultrasound provides a two-dimensional cross-sectional image of the arterial wall and can help assess the plaque burden and composition. Optical coherent tomography offers superior resolution over intravascular ultrasound. High-resolution magnetic resonance imaging provides non-invasive imaging for visualizing fibrous cap thickness and rupture in plaques. In addition, it may be of value in assessing the effects of treatments, such as lipid-lowering therapy. Technical issues however limit its clinical applicability. The role of multi-slice computed tomography, a well established screening tool for coronary artery disease, remains to be determined. Fractional flow reserve (FFR) may provide physiological functional assessment of plaque vulnerability; however, its role in the management of vulnerable plaque requires further studies. Treatment of the vulnerable patient may involve systemic therapy which currently include statins, ACE inhibitors, beta-blockers, aspirin, and calcium-channel blockers and in the future local therapeutic options such as drug-eluting stents or photodynamic therapy.

Liang, Michael; Puri, Aniket; Devlin, Gerard

2011-01-01

413

Assessment of Lymphedema Risk Following Lymph Node Dissection and Radiation Therapy for Primary Breast Cancer.  

National Technical Information Service (NTIS)

Lymphedema is a common, chronic, and potentially devastating complication of primary breast cancer therapy. Radiation increases patients lymphedema risk up to 36% as conventional fields irradiate vital lymphatic tissues. Fusion imaging technologies that c...

A. L. Cheville

2011-01-01

414

Should supplemental antioxidant administration be avoided during chemotherapy and radiation therapy?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Despite nearly two decades of research investigating the use of dietary antioxidant supplementation during conventional chemotherapy and radiation therapy, controversy remains about the efficacy and safety of this complementary treatment. Several studies of concurrent antioxidant administration with...

415

Factors associated with program utilization of radiation therapy treatment for VHA and medicare dually enrolled patients.  

PubMed

We examine how distance to a Veterans Health Administration (VHA) facility, patient hometown classification (e.g., small rural town), and service-connected disability are associated with veterans' utilization of radiation therapy services across the VHA and Medicare. In 2008, 45,914 dually-enrolled veteran patients received radiation therapy. Over 3-quarters (35,513) of the patients received radiation therapy from the Medicare program. Younger age, male gender, shorter distance to a VHA facility, and VHA priority or disability status increased the odds of utilizing the VHA. However, veterans residing in urban areas were less likely to utilize the VHA. Urban dwelling patients' utilization of Medicare instead of the VHA suggests a complex decision that incorporates geographic access to VHA services, financial implications of veteran priority status, and the potential availability of multiple sources of radiation therapy in competitive urban markets. PMID:22139021

French, Dustin D; Bradham, Douglas D; Campbell, Robert R; Haggstrom, David A; Myers, Laura J; Chumbler, Neale R; Hagan, Michael P

2012-08-01

416

[Conformal radiation therapy with or without intensity modulation in the treatment of localized prostate cancer].  

PubMed

Conformal radiation therapy has now to be considered as a standard treatment of localized prostatic adenocarcinomas. Using conformational methods and intensity modulated radiation therapy requires a rigorous approach for their implementation in routine, focused on the reproducibility of the treatment, target volume definitions, dosimetry, quality control, setup positioning. In order to offer to the largest number of patients high-dose treatment, the clinicians must integrate as prognostic factors accurate definition of microscopic extension as well as the tolerance threshold of critical organs. High-dose delivery is expected to be most efficient in intermediary risks and locally advanced diseases. Intensity modulated radiation therapy is specifically dedicated to dose escalation. Perfect knowledge of classical constraints of conformal radiation therapy is required. Using such an approach in routine needs a learning curve including the physicists and a specific quality assurance program. PMID:16095944

Maingon, P; Bolla, M; Truc, G; Bosset, M; Peignaux, K; Ammor, A

2005-08-10

417

Accurate and Fast Localization of Prostate for External Beam Radiation Therapy.  

National Technical Information Service (NTIS)

The development of intensity modulated radiation therapy (IMRT) makes it possible to deliver high precision conformal dose distributions