International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Adequate margins for random setup uncertainties in head-and-neck IMRT.
To investigate the effect of random setup uncertainties on the highly conformal dose distributions produced by intensity-modulated radiotherapy (IMRT) for clinical head-and-neck cancer patients and to determine adequate margins to account for those uncertainties. ⋯ The margins to account for random setup uncertainties, in our clinical IMRT solution, should be 1.5 mm and 3.0 mm in the case of sigma = 2 mm and sigma = 4 mm, respectively, for the CTV(primary). Larger margins (5.0 mm), however, should be applied to the CTV(elective), if the goal of treatment is a V(95) value of at least 99%.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Improved biochemical outcome with adjuvant radiotherapy after radical prostatectomy for prostate cancer with poor pathologic features.
The indications for adjuvant external beam radiotherapy (EBRT) after radical prostatectomy (RP) are poorly defined. We performed a retrospective comparison of our institution's experience treating prostate cancer with RP vs. RP followed by adjuvant EBRT. ⋯ Adjuvant RT demonstrated improved efficacy against prostate cancer. For patients with poor pathologic features (extracapsular extension, seminal vesicle invasion, positive margins), adjuvant RT improved the biochemical outcome independent of other prognostic factors.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Randomized Controlled Trial Multicenter Study Clinical TrialAccelerated versus conventional fractionated postoperative radiotherapy for advanced head and neck cancer: results of a multicenter Phase III study.
To determine whether, in the postoperative setting, accelerated fractionation (AF) radiotherapy (RT) yields a superior locoregional control rate compared with conventional fractionation (CF) RT in locally advanced squamous cell carcinomas of the oral cavity, oropharynx, larynx, or hypopharynx. ⋯ Accelerated fractionation does not seem to be worthwhile for squamous cell carcinoma of the head and neck after resection; however, AF might be an option for patients who delay starting RT.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Clinical TrialPosttreatment TNM staging is a prognostic indicator of survival and recurrence in tethered or fixed rectal carcinoma after preoperative chemotherapy and radiotherapy.
To evaluate the prognostic value of the posttreatment TNM stage as a predictor of outcome in locally advanced rectal cancers treated with preoperative chemotherapy and radiotherapy. ⋯ For patients who underwent preoperative chemoradiotherapy for locally advanced rectal cancer, the pCR TNM stage was a strong prognosticator of recurrence and survival. It can be used to identify high-risk patients for additional postoperative therapy.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Dose-response relationship in locoregional control for patients with stage II-III esophageal cancer treated with concurrent chemotherapy and radiotherapy.
To evaluate the correlation between radiation dose and locoregional control (LRC) for patients with Stage II-III unresectable esophageal cancer treated with concurrent chemotherapy and radiotherapy. ⋯ Our data suggested a positive correlation between radiation dose and LRC in the population studied. A higher radiation dose was associated with increased LRC and survival in the dose range studied. The data also suggested that better LRC was associated with a lower rate of distant metastasis. A threshold of tumor response to radiation dose might be present, as suggested by the flattened slope in the high-dose area on the dose-response curve. A carefully designed dose-escalation study is required to confirm this assumption.