Impact Of Hormone Receptor Status On The Prognosis Of Non-metastatic Neuroendocrine Carcinoma Of The Breast

Purpose:Neuroendocrine carcinoma of the breast(NECB)is a rare subtype of mammary carcinoma,of which the prognosis is still controversial.Research on non-metastatic NECB is even less available.The aim of this analysis was to evaluate the clinicopathologic prognostic factors as well as survival outcomes of patients with non-metastatic NECB.Patients and methods:Patients diagnosed with NECB from 2003-2015 in the Surveillance,Epidemio-logy and End Results(SEER)database were searched.Screening was performed strictly according to inclusion as well as exclusion criteria,and 220 eligible female patients with non-metastatic NECB were most screened.The study cohort was divided into hormone receptor positive and hormone receptor negative groups according to their hormone receptor status.Kaplan-Meier method and Cox proporti-onal hazard regression model were used to assess factors associated with breast cancer specific survival(BCSS)as well as overall survival(OS)in patients with non-metastatic NECB.To further control for potential baseline confounders between the two groups,a 1:1 propensity to match analysis(PSM)with a matching tolerance of 0.02 was performed according to the types of variables: age,race,histologic,grade,tumor size,lymph node,surgery,radiotherapy,and chemotherapy.Data analysis was performed using SPSS 25.0 software to draw conclusions,and graphpad prism 8.0software was applied for plotting.Results:1,220 Of the patients with non-metastatic NECB,63.4% were hormone receptor positive(n=138)and 37% were hormone receptor negative(n=82).Hormone receptor-positive patients had lower tumor histologic grade(13.4% vs.3.7%),smaller volume tumors(40.1% vs.20.7%),fewer small cell carcinoma types(55.6% vs.44.3%)and AJCC stage III patients(13.0% vs.26.8%)compared to the hormone receptor-negative group,and more patients underwent surgery(93.0% vs 84.1%)and lower chemotherapy rates(all P values less than 0.05)2.In Kaplan-Meier survival analysis,hormone receptor-positive patients had a better five-year BCSS than hormone receptor-negative patients,as verified in a multivariate Cox regression model(HR: 0.395,95%,p=0.016).The results were further confirmed in a 1:1 matched group.While no survival benefit was found in the OS3 Subgroup analysis showed that patients with dual positive estrogen receptor(ER)and progesterone receptor(PR)had better BCSS than hormone receptor negative patients,especially for AJCC stage II and III patients.Conclusion:Hormone receptor status is an important prognostic factor for patients with non-metastatic NECB.Breast cancer-specific survival rates were significantly higher in hormone receptor-positive non-metastatic NECB patients than in hormone receptor-negative patients,even after eliminating confounding factors in baseline characteristics using propensity matching.Patients with more advanced staging who are both ER and PR positive have better BCSS compared to hormone receptor negative patients...