Purpose: To investigate clinicopathologic characteristics and prognosis in secretory breast carcinoma (SBC) and to determine chemotherapy benefits stratified by different subgroups.
Methods: SBCs and triple-negative invasive ductal carcinoma patients (TN-IDCs) were enrolled from three cancer centers between January 2011 and December 2020. SBCs were further divided into two subgroups: those with triple negativity (TN-SBCs) and those without (non-TN-SBCs). Clinicopathologic characteristics were thoroughly compared among the three subgroups associated with triple negativity. Kaplan-Meier estimates and Cox proportional hazard models were performed for survival analysis.
Results: A total of 80 SBCs and 310 TN-IDCs were included in the study. The TN-SBC subgroup consisted of 35 individuals (43.75%) with mild clinical behaviors and a satisfying prognosis in comparison to non-TN-SBCs and TN-IDCs. In SBCs, N stage (N1 vs. N0: HR = 11.176, 95% CI 0.843-148.132, p = 0.067; N2-3 vs. N0: HR = 30.409, 95% CI 1.378-671.169, p = 0.031), LNR (HR = 23.894, 95% CI 1.614-353.835, p = 0.021), and histological grade (HR = 28.634, 95% CI 2.745-298.703, p = 0.005) were significantly correlated with disease-free survival (DFS). Patients in high LNR group receiving chemotherapy achieved a prolonged DFS (p = 0.025), while chemotherapy did not confer a survival benefit in TN-SBCs of our interest (p = 0.12).
Conclusion: TN-SBC is a unique entity with low malignant potential. Advanced N stage, high LNR, and advanced histological grade are adverse determinants of DFS in SBC. Adjuvant chemotherapy provides superior DFS in high LNR SBCs rather than TN-SBCs, hence it is recommended for high LNR SBCs.
Keywords: Chemotherapy; Clinicopathologic characteristics; Prognosis; Secretory breast carcinoma; Triple negativity.
© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.