Association between Lymphovascular Invasion and Recurrence in Patients with pT1N+ or pT2–3N0 Gastric Cancer: a Multi-institutional Dataset Analysis

PURPOSE: Patients with pathological stage T1N+ or T2–3N0 gastric cancer may experience disease recurrence following curative gastrectomy. However, the current Japanese Gastric Cancer Treatment Guidelines do not recommend postoperative adjuvant chemotherapy for such patients. This study aimed to identify the prognostic factors for patients with pT1N+ or pT2–3N0 gastric cancer using a multi-institutional dataset. MATERIALS AND METHODS: We retrospectively analyzed the data obtained from 401 patients with pT1N+ or pT2–3N0 gastric cancer who underwent curative gastrectomy at 9 institutions between 2010 and 2014. RESULTS: Of the 401 patients assessed, 24 (6.0%) experienced postoperative disease recurrence. Multivariate analysis revealed that age ≥70 years (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.09–7.23; P=0.030) and lymphatic and/or venous invasion (lymphovascular invasion (LVI): HR, 7.88; 95% CI, 1.66–140.9; P=0.005) were independent prognostic factors for poor recurrence-free survival. There was no significant association between LVI and the site of initial recurrence. CONCLUSIONS: LVI is an indicator of poor prognosis in patients with pT1N+ or pT2–3N0 gastric cancer.