skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Benefit of Radiation Boost After Whole-Breast Radiotherapy

Journal Article · · International Journal of Radiation Oncology, Biology and Physics
 [1];  [1];  [2];  [3]; ; ; ; ;  [1];  [4];  [5];  [1]
  1. Radiotherapy Unit, University of Florence, Florence (Italy)
  2. Molecular and Nutritional Epidemiology Unit, ISPO, Cancer Prevention and Research Institute, Florence (Italy)
  3. Department of Gynaecology, Perinatology and Human Reproduction, University of Florence, Florence (Italy)
  4. Department of Pathology, University of Florence, Florence (Italy)
  5. Department of Surgery, University of Florence, Florence (Italy)

Purpose: To determine whether a boost to the tumor bed after breast-conserving surgery (BCS) and radiotherapy (RT) to the whole breast affects local control and disease-free survival. Methods and Materials: A total of 1,138 patients with pT1 to pT2 breast cancer underwent adjuvant RT at the University of Florence. We analyzed only patients with a minimum follow-up of 1 year (range, 1-20 years), with negative surgical margins. The median age of the patient population was 52.0 years (+-7.9 years). The breast cancer relapse incidence probability was estimated by the Kaplan-Meier method, and differences between patient subgroups were compared by the log rank test. Cox regression models were used to evaluate the risk of breast cancer relapse. Results: On univariate survival analysis, boost to the tumor bed reduced breast cancer recurrence (p < 0.0001). Age and tamoxifen also significantly reduced breast cancer relapse (p = 0.01 and p = 0.014, respectively). On multivariate analysis, the boost and the medium age (45-60 years) were found to be inversely related to breast cancer relapse (hazard ratio [HR], 0.27; 95% confidence interval [95% CI], 0.14-0.52, and HR 0.61; 95% CI, 0.37-0.99, respectively). The effect of the boost was more evident in younger patients (HR, 0.15 and 95% CI, 0.03-0.66 for patients <45 years of age; and HR, 0.31 and 95% CI, 0.13-0.71 for patients 45-60 years) on multivariate analyses stratified by age, although it was not a significant predictor in women older than 60 years. Conclusion: Our results suggest that boost to the tumor bed reduces breast cancer relapse and is more effective in younger patients.

OSTI ID:
21367496
Journal Information:
International Journal of Radiation Oncology, Biology and Physics, Vol. 75, Issue 4; Other Information: DOI: 10.1016/j.ijrobp.2008.12.038; PII: S0360-3016(09)00025-X; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0360-3016
Country of Publication:
United States
Language:
English