Treatment Regimens and Survival Outcomes of Primary Neuroendocrine Carcinoma of Breast Compared with Infiltrating Ductal Carcinoma: A Large Propensity Score Matching Study

Abstract Purpose The role of treatment regimens in Neuroendocrine carcinoma of breast (NECB) is not well defined. The aim of this study was to explore the clinical characteristics, treatment regimens and prognosis of NECB compared to infiltrating ductal breast carcinomas(IDCB).Method NECB and IDCB patients diagnosed between January 1,2004 and December 12,2016 were enrolled in the researches from the SEER registries. A propensity score matching (PSM) with ratio of 1:5 was performed to correct the selection bias. The Kaplan-Meier curves was used in the analysis of variables. The Cox model was adopted to calculate univariate and multivariate analysis.Results Compared to IDCB, NECB patients were elder white females. The NECB group demonstrated a significantly poorer survival compared to IDCB group in both disease-specific survival (DSS) (p<0.0001) and overall survival (OS) (P<0.0001). In univariate survival analysis, NECB patients were associated with poorer survival compared with IDCB patients. In multivariate survival analysis, earlier T stage, age <60, black race and absence of distant metastasis were independently associated with better DSS and OS after adjusting all variables. In both univariate and multivariate analysis, chemotherapy and surgery were independently associated with better survival. Conclusion NECB were a kind of rare and aggressive breast neoplasm with advanced disease stage and pooper prognosis compared to IDCB. Our outcomes supplied sufficient evidence that surgery and chemotherapy contribute to better survival of NECB patients.