Natsuko Tanaka1, Akira Hirano2, Akinori Hattori1, Kaoru Ogura1, Mari Kamimura1, Hiroaki Inoue1,3, Hiroko Yukawa1, Shiho Sakaguchi1, Aya Matsuoka1, Asaka Kodera1, Tadao Shimizu1. 1. Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishi-ogu, Arakawa-ku, Tokyo, 116-8567, Japan. 2. Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishi-ogu, Arakawa-ku, Tokyo, 116-8567, Japan. hirano.akira@twmu.ac.jp. 3. Department of Thoracic, Endocrine Surgery and Oncology, Tokushima University Graduate School of Biomedical Sciences, Tokushima, Japan.
Abstract
BACKGROUND: Survival benefits of chemotherapy (CT) differ among patients with estrogen receptor-positive (ER +) breast cancer. This study investigated the survival benefits of CT for ER + and human epidermal growth factor receptor 2-negative (HER2-) breast cancer (BC) patients by propensity score matching (PSM). METHODS: Patients with stages I-IIIER + /HER2- BC were enrolled in this study. The primary endpoints were 5-year recurrence-free survival (RFS) and overall survival (OS) in the non-CT and CT groups of the selected population matched by PS. The PS was analyzed by a logistic regression model with factors those influence provided indication of chemotherapy [tumor size, nuclear grade (NG), progesterone receptor, and nodal status]. RESULTS: This study enrolled 895 patients between 2000 and 2015. The median follow-up period was 5.7 years. Overall, the 5-year RFS was 94.3% and 90.1% in the non-CT and CT-treated groups, respectively (p = 0.106). The 5-year OS was 97.5% in the non-CT group and 95.6% in the CT group (p = 0.047). Using PSM, 236 patients were selected. After matching, both the 5-year RFS and the 5-year OS were higher in the CT group than in the non-CT group (96.8% vs. 82.7%, p = 0.003 and 100% vs. 91.9%, p < 0.001, respectively). Particularly in the case of the node negative/NG3 and 1-3 node positive/NG2 patients after PSM, the 5-year RFS was significantly higher in the CT group than in the non-CT group (p = 0.041 and p = 0.006, respectively). CONCLUSION: After PSM, CT significantly improved both the RFS and OS of ER + / HER2- BC patients, especially for node negative/NG3 and 1-3 node positive/NG2 patients.
BACKGROUND: Survival benefits of chemotherapy (CT) differ among patients with estrogen receptor-positive (ER +) breast cancer. This study investigated the survival benefits of CT for ER + and humanepidermal growth factor receptor 2-negative (HER2-) breast cancer (BC) patients by propensity score matching (PSM). METHODS:Patients with stages I-IIIER + /HER2- BC were enrolled in this study. The primary endpoints were 5-year recurrence-free survival (RFS) and overall survival (OS) in the non-CT and CT groups of the selected population matched by PS. The PS was analyzed by a logistic regression model with factors those influence provided indication of chemotherapy [tumor size, nuclear grade (NG), progesterone receptor, and nodal status]. RESULTS: This study enrolled 895 patients between 2000 and 2015. The median follow-up period was 5.7 years. Overall, the 5-year RFS was 94.3% and 90.1% in the non-CT and CT-treated groups, respectively (p = 0.106). The 5-year OS was 97.5% in the non-CT group and 95.6% in the CT group (p = 0.047). Using PSM, 236 patients were selected. After matching, both the 5-year RFS and the 5-year OS were higher in the CT group than in the non-CT group (96.8% vs. 82.7%, p = 0.003 and 100% vs. 91.9%, p < 0.001, respectively). Particularly in the case of the node negative/NG3 and 1-3 node positive/NG2 patients after PSM, the 5-year RFS was significantly higher in the CT group than in the non-CT group (p = 0.041 and p = 0.006, respectively). CONCLUSION: After PSM, CT significantly improved both the RFS and OS of ER + / HER2- BC patients, especially for node negative/NG3 and 1-3 node positive/NG2 patients.
Entities:
Keywords:
Adjuvant chemotherapy; Breast cancer; Propensity score matching