International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1992
Survival following locoregional recurrence of breast cancer: univariate and multivariate analysis.
Although prognostic variables for locoregional recurrence of breast cancer have been evaluated by univariate analysis, multifactorial analysis has not been previously performed. In the present study, survival following chest wall and/or regional lymphatic recurrence was determined in 230 patients with locoregionally recurrent breast cancer without evidence of distant metastases treated at the Radiation Oncology Center, Mallinckrodt Institute of Radiology and affiliated hospitals. Multifactorial analysis demonstrated that the site of recurrences correlated most strongly with overall survival (p = 0.001). ⋯ In the subset of patients with small chest wall recurrences (excised or less than 3 cm) and a disease-free interval of at least 2 years, the 5-year overall and disease-free survivals were 67% and 54%, respectively. These results suggest that subsets of patients with locoregional recurrence of breast cancer can survive for long periods of time. The conventional wisdom that chest wall and/or regional nodal recurrence following mastectomy uniformly confers a dismal prognosis is not necessarily true.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1992
Outcome of conservative therapy for invasive breast cancer by histologic subtype.
Between 1977 and 1986, 879 patients with Stage I and II breast cancer underwent excisional biopsy, axillary dissection, and radiation. Median follow-up was 61 months (range 2-159 months). The patients were divided into seven groups based on histologic subtype: (a) 368 patients with both infiltrating and intraductal ductal carcinoma, (b) 389 infiltrating ductal carcinoma, (c) 41 infiltrating lobular carcinoma, (d) 23 combined infiltrating ductal and lobular carcinoma, (e) 28 medullary carcinoma, (f) 12 colloid carcinomas, and (g) 18 tubular carcinomas. ⋯ The site of in-breast failure relative to the location of the original tumor was not significantly different between groups. The histologic subtype of invasive breast cancer is not an independent risk factor in predicting survival or pattern of failure. Conservative surgery and radiation therapy is effective treatment of ductal, lobular, medullary, colloid, and tubular invasive breast cancer.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1992
Thermoradiotherapy for residual microscopic cancer: elective or post-excisional hyperthermia and radiation therapy in the management of local-regional recurrent breast cancer.
A Phase I/II study was undertaken to investigate the efficacy and side effects of combined hyperthermia and radiation therapy in the management of presumed or known microscopic residual tumors. Between February 1985 and March 1991, 262 fields in 89 patients with local-regional recurrent breast cancer were treated with externally administered hyperthermia and radiation therapy. Thirty-eight fields were treated for microscopic residual disease following excisional biopsy of nodular recurrences and 224 fields were treated electively for areas at high risk for local recurrences adjacent to fields with macroscopic residual disease. ⋯ Parameters in the best five covariate model correlating with the duration of local control included: estrogen receptor status of the initial breast cancer; initial T-stage; time from initial breast cancer to first failure; age at hyperthermia; and concurrent radiation dose (p-value for model less than 0.000001). Six covariate models adding anatomic site of disease, field type, mean minimum temperatures, and mean percent temperatures greater than or equal to 40 degrees C all resulted in improved models. Randomized controlled studies stratifying for these pretreatment parameters are felt warranted to confirm the value of adjuvant hyperthermia in the elective treatment of areas of high risk for local-regional recurrent breast cancer and in fields following surgical excision of recurrent disease, particularly in patients in whom full dose radiation therapy cannot be safely administered.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1992
Post-mastectomy radiotherapy following adjuvant chemotherapy and autologous bone marrow transplantation for breast cancer patients with greater than or equal to 10 positive axillary lymph nodes. Cancer and Leukemia Group B.
Between 2/87 and 2/91, 49 women with operable breast cancer involving greater than or equal to 10 axillary nodes were treated following mastectomy, with four cycles of Cyclophosphamide, Adriamycin, 5FU, followed by high doses of Cyclophosphamide, Cisplatin, Carmustine (HDCT) with autologous bone marrow transplant support. Forty patients received local-regional radiotherapy (generally to the chest wall, internal mammary, supraclavicular, +/- axillary nodal areas; minimum 44-50 Gy, 1.8-2 Gy/fraction, +/- 10-15 Gy scar boost; standard radiation techniques). The first nine patients did not receive local-regional radiotherapy. ⋯ Further studies to determine the roles of local-regional radiotherapy and HDCT in the development of these toxicities are underway. These encouraging results suggest that HDCT + autologous bone marrow transplant+local-regional radiotherapy may improve the survival rate in these high risk patients. A national randomized study to test the efficacy of this HDCT regimen is currently underway (Cancer and Leukemia Group B#9082 and Southwest Oncology Group #9114).
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1992
Comparative StudyPulsed brachytherapy: the conditions for no significant loss of therapeutic ratio compared with traditional low dose rate brachytherapy.
Pulsed brachytherapy consists of using a stronger radiation source than for traditional low dose-rate brachytherapy, but giving a series of short exposures of 10 to 30 min in every hour, to approximately the same total dose in the same overall time as with the low dose-rate. Calculations based on the linear quadratic model, in which the beta x dose squared component only is assumed to be repairable, and at a monoexponential rate, show that there is no significant loss of therapeutic ratio, defined as tumor damage for a given level of late damage. Some loss of therapeutic ratio would in principle be expected when dose rates are increased, but, in the presently proposed applications, there are so many small pulses (fractions at medium or low dose-rate) that even though repair is not usually complete between them, the relative increase of late damage (in units proportional to log cell kill) is less than 10% more than the increase of tumor damage, except in unlikely conditions that we define. Although these calculations suggest that pulsed brachytherapy should be safe for pulse repetition frequencies up to about 2 hr, using dose rates not exceeding about 3 Gy/hr, we discuss the radiobiological reservations and the limitations of such calculations.