International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Review Meta AnalysisProposal of human spinal cord reirradiation dose based on collection of data from 40 patients.
Driven by numerous reports on recovery of occult radiation injury, reirradiation of the spinal cord today is considered a realistic option. In rodents, long-term recovery was observed to start at approximately 8 weeks. However, prospective clinical studies are lacking. Therefore, a combined analysis of all published clinical data might provide a valuable basis for future trials. ⋯ On the basis of these literature data (and with due caution), the risk of myelopathy appears small after < or =135.5 Gy(2) when the interval is not shorter than 6 months and the dose of each course is < or =98 Gy(2). We would recommend limiting the dose to this level, whenever technically feasible. However, it appears prudent to propose the collection of prospective data from a greater number of patients receiving doses in the range of 136-150 Gy(2) to assess the safety of higher retreatment doses for those patients in whom limited doses might compromise tumor control.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
ReviewIntegration of surgery with fractionated stereotactic radiotherapy for treatment of nonfunctioning pituitary macroadenomas.
To evaluate the efficacy of fractionated stereotactic radiotherapy (FSRT) after surgery in the management of residual or recurrent nonfunctioning pituitary adenomas with respect to tumor control and the development of complications. ⋯ The findings of this analysis support the use of surgery followed by FSRT as a safe, effective, and integrated treatment for nonfunctioning pituitary adenomas. Additional follow-up is needed to document the long-term tumor control rates, preservation rates for vision and pituitary function, and neurocognitive outcomes.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Clinical TrialThe impact of daily setup variations on head-and-neck intensity-modulated radiation therapy.
Intensity-modulated radiation therapy (IMRT) in the treatment of head-and-neck (H&N) cancer provides the opportunity to diminish normal tissue toxicity profiles and thereby enhance patient quality of life. However, highly conformal treatment techniques commonly establish steep dose gradients between tumor and avoidance structures. Daily setup variations can therefore significantly compromise the ultimate precision of idealized H&N IMRT delivery. This study provides a detailed analysis regarding the potential impact of daily setup variations on the overall integrity of H&N IMRT. ⋯ The successful implementation of H&N IMRT requires accurate and reproducible treatment delivery over a 6- to 7-week treatment course. The adverse impact of daily setup variation, which occurs routinely with conventional H&N masking techniques, may be considerably greater than recognized. Isocenter verification checks on two-dimensional orthogonal films may not sufficiently alert the clinician to the magnitude of three-dimensional offset vectors and the resultant impact on the quality of overall IMRT delivery. Unrecognized geographic miss and resultant target underdose may occur. Similarly, selected normal structures such as parotid glands may receive higher doses than intended. The results of this study suggest that more rigorous immobilization techniques than conventional masking and routine patient setup tracking methodologies are important for the accurate monitoring and successful delivery of high-quality IMRT for H&N cancer.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2005
Role of prostate dose escalation in patients with greater than 15% risk of pelvic lymph node involvement.
To determine whether the radiation dose is a determinant of clinical outcome in patients with a lymph node risk of >15% treated using whole pelvic (WP), partial pelvic (PP), or prostate only (PO) fields. ⋯ The radiation dose was the most significant determinant of FFBF in patients with a lymph node risk >15% in the patient population studied. These data suggest that the primary tumor takes precedence over lymph node coverage or the use of STAD. Doses >70 Gy are of paramount importance in such intermediate- and high-risk patients.
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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.