The Japanese Breast Cancer Society clinical practice guideline for radiotherapy of breast cancer

Abstract

Clinical questions (CQs) were divided into five sections:(1) Radiotherapy after breast-conserving surgery for stage I-II breast cancer.(2) Radiotherapy after breast-conserving surgery for ductal carcinoma in situ (DCIS). (3) Contraindication for breast-conserving therapy. (4) Post-mastectomy radiotherapy (PMRT) for advanced breast cancer. (5) Radiotherapy for metastasis.Radiotherapy after breast-conserving surgery for stage I-II breast cancer CQ1. Is radiotherapy following breast-conserving surgery recommended for patients with stage I-II breast cancer? RecommendationRadiotherapy should be recommended (Grade A).Although breast-conserving surgery without radiotherapy is performed for some of patients with early-stage breast cancer in Japan, it was found that the rate of local recurrence in the conserved breast was significantly decreased in seven randomized controlled trials (RCTs) from different parts of the world [1-7], a meta-analysis of these clinical trials analyzed by the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) [8] with the conclusion that postoperative radiotherapy is essential. The recent meta-analysis of these RCTs confirmed that postoperative radiotherapy significantly improved patient survival rates [8,9].