International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 1999
Patients with early stage invasive cancer with close or positive margins treated with conservative surgery and radiation have an increased risk of breast recurrence that is delayed by adjuvant systemic therapy.
The association between a positive resection margin and the risk of ipsilateral breast tumor recurrence (IBTR) after conservative surgery and radiation is controversial. The width of the resection margin that minimizes the risk of IBTR is unknown. While adjuvant systemic therapy may decrease the risk of an IBTR in all patients, its impact on patients with positive or close margins is largely unknown. This study examines the interaction between margin status, margin width, and adjuvant systemic therapy on the 5- and 10-year risk of IBTR after conservative surgery and radiation. ⋯ A negative margin (> 2 mm) identifies patients with a very low risk of IBTR (7% at 10 years) after conservative surgery and radiation. Patients with a close margin (< or = 2 mm) are at an equal or greater risk of IBTR as with a positive margin, especially following a reexcision. A margin involved by DCIS or invasive tumor has the same increased risk of IBTR. A reexcision of an initially close or positive margin that results in a negative final margin reduces the risk of IBTR to that of an initially negative margin. A close or positive margin is associated with an increased risk of IBTR even in patients who are EIC-negative or receiving higher boost doses of radiation. The median time to IBTR is delayed; however, the CI is not significantly decreased by adjuvant systemic therapy in patients with close or positive margins-the 5 year results in these patients underestimate their ultimate risk of recurrence.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 1999
The dependence of prostate postimplant dosimetric quality on CT volume determination.
The postoperative evaluation of permanent prostate brachytherapy requires a subjective determination of the implant volume. This work investigates the magnitude of the effect that various methods of treatment volume delineation have on dosimetric quality parameters for a treatment planning philosophy that defines a target volume as the prostate with a periprostatic margin. ⋯ In terms of a logarithmic measure, the variation between volumetric approach for V100, V150, V200, and D90 was less than one-fifth the variation of the CT volumes. These results which indicate relative independence of postimplant CT volume determination and dosimetric quality are only valid for a planning philosophy that includes the prostate with a periprostatic margin as the target volume.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 1999
Intensified adjuvant therapy for pancreatic and periampullary adenocarcinoma: survival results and observations regarding patterns of failure, radiotherapy dose and CA19-9 levels.
Primary endpoints were 1. To determine if, in the context of postoperative adjuvant therapy of pancreatic and nonpancreatic periampullary adenocarcinoma, continuous infusion (C.I.) 5-fluorouracil (5-FU) and leucovorin (Lv), combined with continuous-course external-beam radiotherapy (EBRT) to liver (23.4-27.0 Gy), regional lymph nodes (50.4-54.0 Gy) and tumor bed (50.4-57.6 Gy), followed by 4 months of C.I. 5-FU/Lv without EBRT could be given with acceptable toxicity. 2. To determine an estimate of disease-free and overall survival (DFS, OS) with this treatment in this context. Secondary endpoints were 1. To observe the effects of therapy at two different dose levels of irradiation, and 2. To observe for correlations among DFS, OS and CA 19-9 levels during therapy. ⋯ Although toxicity was acceptable, survival results were not improved over those seen with standard adjuvant treatment. Most patients relapsed before the planned chemotherapy cycles were completed, or within 100 days thereof, suggesting disease resistance to C.I. 5-FU/Lv as used in this study. Although this regimen is not recommended for further study, the doses of EBRT utilized may be suitable for evaluation with other chemotherapy combinations. Postoperative CA 19-9 levels did not correlate with survival, but did correlate with the number of histologically involved lymph nodes found in the resected specimen among node-positive patients. Moreover, rising CA 19-9 levels anticipated ultimate clinical failure by 9 months.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 1999
Radiotherapy following mastectomy: indication and contraindication of chest wall irradiation.
To determine in which cases radiotherapy of the chest wall following mastectomy is indicated, based on the local recurrent rate in patients with locally advanced breast cancer. ⋯ Among patients with breast cancer who have four or more positive axillary nodes or T3-4Nany, those who have no vascular invasion or less than 4 axillary nodes metastases do not need to be subjected to chest wall irradiation after radical mastectomy.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 1999
Review Practice Guideline GuidelineAmerican Brachytherapy Society (ABS) recommendations for transperineal permanent brachytherapy of prostate cancer.
To develop and disseminate the American Brachytherapy Society (ABS) recommendations for the clinical quality assurance and guidelines of permanent transperineal prostate brachytherapy with 125I or 103Pd. ⋯ Guidelines for appropriate patient selection, dose reporting, and improved quality of permanent prostate brachytherapy are presented. These broad recommendations are intended to be technical and advisory in nature, but the ultimate responsibility for the medical decisions rests with the treating physician. This is a constantly evolving field, and the recommendations are subject to modifications as new data becomes available.