Recurrence in node-negative advanced gastric cancer: Novel findings from an in-depth pathological analysis of prognostic factors from a multicentric series

AIM: To analyze the clinicopathological characteristics of patients with both node-negative gastric carcinoma and diagnosis of recurrence during follow-up. METHODS: We enrolled 41 patients treated with curative gastrectomy for pT2-4aN0 gastric carcinoma between 1992 and 2010, who developed recurrence (Group 1). We retrospectively selected this group from the prospectively collected database of 4 centers belonging to the Italian Research Group for Gastric Cancer, and compared them with 437 pT2-4aN0 patients without recurrence (Group 2). We analyzed lymphatic embolization, microvascular infiltration, perineural infiltration, and immunohistochemical determination of p53, Ki67, and HER2 in Group 1 and in a subgroup of Group 2 (Group 2bis) of 41 cases matched with Group 1 according to demographic and pathological characteristics. RESULTS: T4a stage and diffuse histotype were associated with recurrence in the group of pN0 patients. In-depth pathological analysis of two homogenous groups of pN0 patients, with and without recurrence during longterm follow-up (groups 1 and 2bis), revealed two striking patterns: lymphatic embolization and perineural infiltration (two parameters that pathologists can easily report), and p53 and Ki67, represent significant factors for recurrence. CONCLUSION: The reported pathological features should be considered predictive factors for recurrence and could be useful to stratify node-negative gastric cancer patients for adjuvant treatment and tailored follow-up.