The impact of pathological lymph node metastasis with lymphatic invasion on the survival of patients with clinically node-negative non-small cell lung cancer: A multicenter study.

Abstract Objectives Lymphatic vessel invasion (Ly) plays a crucial role in pathological lymph node metastasis (pN), and we consider pN + Ly + disease to indicate a high affinity for the lymphatic system. This study evaluated the outcomes of patients with clinically node-negative (N0) non-small cell lung cancer (NSCLC) who presented with pN + with Ly+. Materials and Methods This retrospective study evaluated 1775 patients with clinically N0 stage I–III NSCLC who underwent R0 anatomical resection and systematic lymph node dissection at three institutions between January 2010 and December 2017. Patients were classified into four groups according to their pN and Ly statuses. Univariable and multivariable analyses were performed to identify factors associated with poor recurrence-free survival (RFS) and pN + Ly+. Results Kaplan-Meier curves revealed that the 5-year RFS rates were 90.8 % for pN–Ly– patients, 55.6 % for pN–Ly + patients, 63.4 % for pN + Ly– patients, and 41.3 % for pN + Ly + patients. Distant and lymph node recurrences were more common in the pN + Ly + group, relative to in the pN–Ly– and pN–Ly + groups (both p  > 1.80 cm and a SUVmax of > 3.55. Conclusion pN and Ly statuses were independent prognostic factors in patients with clinically N0 stage I–III NSCLC. Diseases presenting with pN + with Ly + were associated with increased rates of distant and lymph node recurrence.