Clinicopathological features of breast cancer patients with nipple discharge

The demographic features and prognostic profiles of breast cancer patients with nipple discharge (ND) have not been well elucidated in previous studies. We therefore performed a retrospective study of female unilateral breast cancer patients that underwent surgery. According to the initial symptoms at diagnosis, a total of 3,317 patients were categorized into the ND (2.74%) and non-ND (NND; 97.26%) subgroups. Survival curves were performed with the Kaplan-Meier method and annual recurrence hazard was estimated by the hazard function. The proportion of larger tumors was lower in patients with ND than in the NND subgroup (P=0.019). In addition, 22.22% of patients with ND had positive lymph nodes in the axilla as compared to 51.06% of those without ND (P<0.001). Multivariate logistic regression analysis showed that axillary lymph node (ALN) status (P=0.003) and Cathepsin-D status (P=0.025) were independent prognostic factors for ND. In the univariate survival analysis, a significant difference in recurrence-free survival (RFS) was found between patients with and without ND (P=0.014). As ND and ERBB2 status were time-varying covariates (global test, both P<0.05), the Cox non-proportional hazards regression model was used. In this model, ND status (P=0.028; RR=2.174, 95% Cl 1.086-4.351), as well as tumor size (P<0.001; RR=1.779, 95% Cl 1.406-2.250), ALN status (P<0.001; RR=2.257, 95% Cl 1.886-2.702), ERBB2 status (P=0.011; RR=0.759, 95% CI 0.613-0.940) and use of adjuvant chemotherapy (P=0.048; RR=0.642, 95% Cl 0.414-0.995) were independent prognosticators for RFS. Regarding hazard peaks, patients without ND showed an early major recurrence surge peaking at 1.5 years after surgery, while the corresponding peak for the ND subgroup was at 3.5 years. Furthermore, the risk of early recurrence for women with ND was lower than that for the NND subgroup. Our findings suggest that biological behavior and prognostic profiles differ significantly between patients with and without ND. This suggests that further studies are required to elucidate these two distinctive disease entities.