Perineural Invasion Predicts Unfavorable Prognosis in Patients With Invasive Breast Cancer

Background/Aim: Perineural invasion (PNI) is a poor prognostic factor in a variety of cancers. However, the frequency of PNI in invasive breast carcinoma varies among studies, and the prognostic significance of PNI remains unclear. Therefore, we aimed to explore the prognostic value of PNI in breast cancer patients. Patients and Methods: The cohort included 191 consecutive female patients who underwent surgical resection of invasive carcinoma of no special type (NOS). The correlations between PNI and clinicopathological characteristics including prognosis were investigated. Results: The frequency of PNI was 14.1% (27/191) and the PNI-positive status was significantly correlated with large pathological tumor size (p=0.005), lymph node metastasis (p=0.001), and lymphatic invasion (p=0.009). The log-rank test showed that PNI-positive patients had shorter distant metastasis-free survival (DMFS) (p=0.002) and disease-specific survival (DSS) (p<0.001). According to the multivariate analysis, PNI had a significant adverse effect on DMFS (p=0.037) and DSS (p=0.003). Conclusion: PNI could be used as an independent poor prognostic indicator in patients with invasive breast carcinoma.