Impact of Presenting Stage on Overall Survival in Patients Treated with Neoadjuvant Chemotherapy for Triple Negative Breast Cancer.

ABSTRACT

PURPOSE: For operable triple-negative breast cancer (TNBC) treated with neoadjuvant chemotherapy (NAC), clinical prognostication and postoperative decision-making relies exclusively on whether a pathologic complete response (pCR) is achieved or not. We evaluated whether extent of disease at presentation further influenced overall survival (OS) among patients with pCR or with residual disease (RD) following NAC. METHODS: Patients with stage I-III TNBC who underwent NAC were identified from the National Cancer Database from 2010 to 2019. Overall survival was assessed by disease extent using the Kaplan-Meier method and Cox proportional hazards regression for univariate and multivariable analysis. RESULTS: A total of 35,598 patients met inclusion criteria, and 11,967 achieved pCR. Ten-year OS was 88.5% and varied by cT and cN category at presentation. Best 10-year OS was seen in patients with cT1-2, cN0 (90.9%) and was worst in those with cT3-4, cN2-3 disease (72.0%). A total of 23,631 patients had RD. Ten-year OS was 60.1% and varied by cT and cN category at presentation. Best 10-year OS was seen in patients with cT1-2, cN0 (73.0%) and was worst in those with cT3-4, cN2-3 disease (36.3%). Notably, OS was significantly poorer for patients with cT3-4, cN2-3 disease at diagnosis and pCR versus those with cT1-2 cN0 and RD (aHR 1.30, 95% confidence interval 1.03-1.63, p = 0.03). CONCLUSIONS: Among patients with TNBC, extent of disease at presentation was prognostic for OS independently of response to NAC. Patients with advanced stage at presentation had poorer OS even in the context of pCR. Further investigation is needed to evaluate whether additional adjuvant therapy strategies should be considered for these patients.