International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2005
Comparative StudyInitial experience with megavoltage (MV) CT guidance for daily prostate alignments.
The on-board megavoltage (MV) computed tomography (CT) capabilities of a TomoTherapy Hi*ART unit were used to obtain daily MVCT images of prostate cancer patients. For patient alignment the daily MVCT image needs to be registered with the planning CT image to calculate couch shifts. Three manual techniques of registering the MVCT images with the planning kilovoltage (kV) CT images were evaluated. The techniques are based on visual alignment of (1) fiducial prostate markers, (2) CT anatomy, and (3) kVCT contours. ⋯ The use of fiducial markers for MVCT image guidance is advantageous to reduce the inter-user variability of the image registration. If fiducial markers are not used, anatomy-based registrations outperform contour-based registrations in terms of (1) agreement with a reference alignment and (2) inter-user variability.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2005
Clinical TrialComparing measures of acute bowel toxicity in patients with prostate cancer treated with external beam radiation therapy.
This study strives to compare early measures of bowel toxicity in patients with prostate cancer receiving definitive or adjuvant 3D conformal external beam radiation therapy and concurrent daily endorectal application of amifostine. ⋯ The EPIC questionnaire measurements are most sensitive to changes in acute bowel toxicity through a course of radiotherapy and correlate with RTOG acute toxicity scores. Endoscopic examination of the rectal mucosa at the end and immediate follow-up of a course of therapy does not seem to be informative or reproducible between observers in the acute setting.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2005
An association between preoperative anemia and decreased survival in early-stage non-small-cell lung cancer patients treated with surgery alone.
Surgical resection is the mainstay of therapy for patients presenting with Stage I and II non-small-cell lung cancer (NSCLC). Despite optimal staging and surgery, these patients are still at significant risk for failure. The purpose of this study is to report a retrospective analysis of the outcome of patients treated with surgery alone, as well as to analyze prognostic factors associated with survival. ⋯ In our cohort of mostly Stage I NSCLC patients treated with surgery only, preoperative Hgb <12 mg/dL predicted for worse outcome. This effect was observed even in the traditionally low-risk subgroup of completely resected stage IA patients. Much has been written in the literature about anemia causing possible worsening of tumor hypoxia within solid tumors, thereby increasing radio-resistance. This has been a popular argument to explain poorer outcomes of anemic patients with solid tumors who undergo radiotherapy. However, our data suggest that anemia may be a sign of a more aggressive tumor that is at an increased risk of failure independent of the treatment modality.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2005
TLD skin dose measurements and acute and late effects after lumpectomy and high-dose-rate brachytherapy only for early breast cancer.
This report examines the relationships between measured skin doses and the acute and late skin and soft tissue changes in a pilot study of lumpectomy and high-dose-rate brachytherapy only for breast cancer. ⋯ For high-dose-rate brachytherapy to the lumpectomy site, TLD skin dose was significantly related to acute skin reaction and to pigmentation and telangiectasia at 60 months. An acute skin reaction was also significantly associated with the development of telangiectasia at 60 months. TLD skin dose measurement may allow modification of the brachytherapy implant geometry (dwell times and position) to minimize late skin toxicity.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2005
Neoadjuvant hormone therapy and external-beam radiation for localized high-risk prostate cancer: the importance of PSA nadir before radiation.
To examine the impact of various patient, disease, and treatment characteristics on outcome in patients treated with neoadjuvant hormone therapy (NAHT) and external-beam radiation therapy (EBRT) for clinically localized, high-risk prostate adenocarcinoma (initial prostate-specific antigen [PSA] level >20, Gleason score 8-10 or Stage > or = T3). ⋯ Improved bDFS in patients with high-risk prostate cancer was associated with lower initial PSA level, lower Gleason score, and lower preradiation PSA level. The duration of NAHT did not have an impact on outcomes, but the preradiation PSA was an important predictor of bDFS in high-risk patients.