Risk Factors for Ipsilateral Breast Tumor Recurrence in Triple-Negative or HER2-Positive Breast Cancer Patients Who Achieve a Pathologic Complete Response After Neoadjuvant Chemotherapy

• Published in: Annals of surgical oncology Vol. 28; no. 5; pp. 2545 - 2552
• Main Authors: Ishitobi, Makoto, Matsuda, Naoko, Tazo, Mizuho, Nakayama, Sayuka, Tokui, Ryu, Ogawa, Tomoko, Yoshida, Atsushi, Kojima, Yasuyuki, Kuwayama, Takashi, Nakayama, Takahiro, Yamauchi, Hideko, Nakamura, Seigo, Tsugawa, Koichiro, Hayashi, Naoki
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.05.2021; Springer Nature B.V
• Subjects: Breast cancer; Breast Neoplasms - drug therapy; Breast Neoplasms - surgery; Breast Oncology; Breast surgery; Chemotherapy; Clinical trials; Diagnosis; Disease-Free Survival; Epidermal growth factor; ErbB-2 protein; Humans; Mastectomy, Segmental; Medicine; Medicine & Public Health; Neoadjuvant Therapy; Neoplasm Recurrence, Local - drug therapy; Oncology; Patients; Retrospective Studies; Risk Factors; Surgery; Surgical Oncology; Survival; Tumors
• ISSN: 1068-9265; 1534-4681
• DOI: 10.1245/s10434-020-09176-0

Background Attention has been focused on attempts to eliminate breast surgery for breast cancer patients who achieve a pathologic complete response after neoadjuvant chemotherapy (NAC). However, there are few data on ipsilateral breast tumor recurrence (IBTR) among patients with triple-negative or epidermal growth factor receptor 2-positive (HER2+) tumors who achieve a pathologic complete response after NAC and breast-conserving treatment. Methods Using a multi-institutional retrospective database, this study evaluated the risk factors for IBTR among patients with newly diagnosed stages 1 to 3 breast cancer involving triple-negative or HER2+ tumors who achieved ypT0 after NAC and breast-conserving treatment. Results During a median follow-up period of 4.8 years (range, 0.1–15.5 years), the 5-year IBTR-free survival rate was 95.5%. The breast cancer subtype was not associated with IBTR-free survival. Patients younger than 40 years at diagnosis had significantly worse IBTR-free survival than those who were 40 years of age or older (5-year IBTR-free survival, 87.7 vs 96.9%; p  = 0.002). Conclusions This retrospective study demonstrated that age at diagnosis was independently associated with IBTR-free survival. Special caution is needed when clinical trials analyzing omission of breast surgery after NAC are enrolling younger patients (UMIN-CTR No. UMIN000037067).