Molecular subtypes and axillary downstaging surgery after neoadjuvant chemothera-py for breast cancer / 中国肿瘤临床

ABSTRACT

Objective:To determine the optimal time to perform sentinel lymph node biopsy(SLNB)in patients with clinically node-negative disease and assess clinically node-positive patients who would acquire greater benefits from axillary downstaging surgery af-ter neoadjuvant chemotherapy(NAC).Methods:From October 2010 to November 2017,206 patients with breast cancer who under-went surgery after NAC were included in this retrospective study in Shandong Cancer Hospital Breast Cancer Center.Their clinicopatho-logic data were collected to discuss the correlation between axillary node pathologic complete response(apCR)and different molecu-lar subtypes.Results:Among 206 patients who received NAC,183 patients had clinically node-positive disease.The frequency of apCR after NAC was 33.3%(61/183),which was significantly higher in patients with human epidermal growth factor receptor 2(HER-2)-posi-tive subtype[with targeted therapy,62.1%(18/29);without targeted therapy,34.5%(10/29)]and triple-negative breast cancer(TNBC) (41.0%)(16/39)than in patients with HER-2-negative luminal subtype breast cancer[19.8%(17/86)](P<0.001). Among 23 patients with Cn0 tumors,the rate of positive sentinel lymph nodes after NAC was 26.1%(6/23);this rate was 36.4%(4/11),25.0%(1/4),and 12.5% (1/8)among patients with HER-2-negative luminal subtype breast cancer,TNBC,and HER-2-positive subtype breast cancer,respective-ly.Conclusions:Molecular subtypes could predict the chance of achieving apCR.For patients with clinically node-negative disease,it would be preferable to perform SLNB prior to NAC for patients with HER-2-negative luminal subtype breast cancer.SLNB after NAC for those with TNBC and HER-2-positive subtype breast cancer could decrease the chances of axillary lymph node dissection.For patients with initial clinically node-positive disease converting to clinically node-negative disease after NAC,especially in TNBC and HER-2-posi-tive subtype breast cancer,these patients might benefit more from axillary downstaging surgery after NAC.