International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Randomized Controlled Trial Clinical TrialGastrointestinal toxicity and its relation to dose distributions in the anorectal region of prostate cancer patients treated with radiotherapy.
To study the correlations between the dose distributions in the anorectal region and late GI symptoms in patients treated for localized prostate carcinoma. ⋯ We found evidence that complaints originate from specific regions of the irradiated lower GI tract. Bleeding and mucus loss are probably related to irradiation of the upper part of the rectum. Soiling and fecal incontinence are more likely related to the dose to the anal canal and the lower part of the rectum.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Cost-effectiveness of radiation therapy following conservative surgery for ductal carcinoma in situ of the breast.
To assess the cost-effectiveness of radiation therapy (RT) in patients with ductal carcinoma in situ (DCIS) after breast-conserving surgery (BCS). ⋯ Addition of RT following BCS for patients with DCIS should not be withheld because of concerns regarding its cost-effectiveness.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Randomized Controlled Trial Multicenter Study Clinical TrialAcute and late complications after radiotherapy for prostate cancer: results of a multicenter randomized trial comparing 68 Gy to 78 Gy.
To compare acute and late gastrointestinal (GI) and genitourinary (GU) side effects in prostate cancer patients randomized to receive 68 Gy or 78 Gy. ⋯ Raising the dose to the prostate from 68 Gy to 78 Gy resulted in higher incidences of acute and late GI and GU toxicity, but these differences were not significant, except for late rectal bleeding requiring treatment and late nocturia. Other factors than the studied dose levels appeared to be important in predicting toxicity after radiotherapy, especially previous surgical interventions (abdominal surgery or TURP), hormonal therapy, and the presence of pretreatment symptoms.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Use of deformed intensity distributions for on-line modification of image-guided IMRT to account for interfractional anatomic changes.
Recent imaging studies have demonstrated that there can be significant changes in anatomy from day to day and over the course of radiotherapy as a result of daily positioning uncertainties and physiologic and clinical factors. There are a number of strategies to minimize such changes, reduce their impact, or correct for them. Measures to date have included improved immobilization of external and internal anatomy or adjustment of positions based on portal or ultrasound images. Perhaps the most accurate way is to use CT image-guided radiotherapy, for which the possibilities range from simple correction of setup based on daily CT images to on-line near real-time intensity modulated radiotherapy (IMRT) replanning. In addition, there are numerous intermediate possibilities. In this paper, we report the development of one such intermediate method that takes into account anatomic changes by deforming the intensity distributions of each beam based on deformations of anatomy as seen in the beam's-eye-view. ⋯ Our preliminary results encourage us to believe that deforming intensities taking into account deformation in the anatomy may be a rapid way to produce new treatment plans on-line in near real-time based on daily CT images. The methods we have developed need to be applied to a group of patients for both prostate and head-and-neck cases to confirm the validity of our approach.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Randomized Controlled Trial Clinical TrialWhat pretreatment prostate-specific antigen level warrants long-term androgen deprivation?
Several large randomized prospective studies have demonstrated a survival benefit with the addition of long-term androgen deprivation to definitive radiotherapy for patients with Gleason score 8-10 or T3-T4 prostate cancer. However, these studies were performed before the routine use of prostate-specific antigen (PSA) measurement. The purpose of this study was to determine what pretreatment (initial) PSA (iPSA) level, if any, warrants the addition of long-term androgen deprivation in the PSA era. ⋯ Recursive partitioning techniques defined an iPSA cutpoint of 30 ng/mL for delineating intermediate vs. high risk. Patients with a PSA level >30 ng/mL in the absence of Gleason score >7 or T3 disease do poorly when treated with radiotherapy alone and should be considered for long-term androgen deprivation or other aggressive systemic therapy.