J Cancer 2021; 12(5):1548-1554. doi:10.7150/jca.51125 This issue
1. Department of Radiotherapy and Oncology, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu 214000, P.R. China.
2. Department of Radiotherapy and Oncology, Suzhou Municipal Hospital, Suzhou, Jiangsu 215000, P.R. China.
*These authors contributed equally to this work.
Objective: The purpose of this study was to evaluate the efficacy of two radiotherapy techniques for breast cancer patients with post-mastectomy. The intensity-modulated radiotherapy for treating the chest wall and regional nodes contoured as a whole planning target volume was compared with the conventional segmented 3-dimensional conformal radiotherapy undergoing modified radical mastectomy.
Materials and methods: Patients who received the two post-mastectomy radiation therapies were retrospectively analyzed. The chest wall and supra/infraclavicular region +/- internal mammary nodes were contoured as a whole planning target volume on the planning computed tomography. We evaluated differences in survival, recurrence, and late side effects between the integrated intensity-modulated radiotherapy group and the conventional segmented group.
Results: A total of 223 patients were recruited. The mean follow-up was 104.3 months. Of these patients, 129 received integrated radiotherapy and 94 patients received segmented radiotherapy. The 8-year disease-free survival rates were 86.0% and 73.4% for patients treated with integrated radiotherapy and traditional segmented radiotherapy, respectively (P = 0.022). The 8-year overall survival rates were 91.4% and 86.2% for patients treated with integrated radiotherapy and traditional segmented radiotherapy, respectively (P = 0.530). Multivariate analysis demonstrated that radiotherapy was an independent prognostic factor for disease-free survival. No significant difference was observed in late side-effects between the two groups.
Conclusion: Intensity-modulated radiotherapy for treating the chest wall and regional nodes contoured as a whole planning target volume reduces the recurrence rate for post-mastectomy breast cancer patients with tolerable toxicities.
Keywords: breast cancer, modified radical mastectomy, intensity modulation, late toxicity