The influences of peritumoral lymphatic invasion and vascular invasion on the survival and recurrence according to the molecular subtypes of breast cancer.

Purpose: We aimed to compare the influences of lymphatic invasion (LI) and vascular invasion (VI) on survival and recurrence according to the molecular subtypes of breast cancer.

Methods: We retrospectively analyzed data on 820 breast cancer patients and assessed overall survival (OS) and disease-free survival (DFS) according to LI and VI using the Kaplan-Meier estimator and the Cox proportional hazards model.

Results: Both positive LI and positive VI showed inferior OS and DFS compared with negative LI and negative VI (all p < 0.001). Both positive LI and positive VI showed higher local, regional, and distant recurrence rates (p = 0.002 for regional recurrence of VI, p < 0.001 for all the others). Although LI was a significant independent predictor of OS (hazard ratio [HR] 1.927; 95% confidence interval [CI] 1.046-3.553) and DFS (HR 1.815; 95% CI 1.063-3.096), VI was not in the multivariate analyses. Regarding OS, both positive LI and positive VI showed worse survival rates in the luminal A (p = 0.016 and p = 0.024, respectively) and triple negative subtypes (both p < 0.001). Regarding DFS, LI was a significant prognosticator in the luminal A and triple negative (both p < 0.001) subtypes. VI was a significant prognosticator across all molecular subtypes, although the prognostic impact was most prominent in the luminal A subtype (p < 0.001).

Conclusions: Both LI and VI were significant, unfavorable prognostic factors of OS and DFS, especially in the luminal A and triple negative breast cancer subtypes. Although LI was a significant independent predictor of OS and DFS, VI was not after the multivariate analyses.