Individualized proximal margin correlates with outcomes in gastric cancers with radical gastrectomy

The length of proximal margin for gastrectomy remains controversial. The proximal margin and its relationships with clinicopathological variables and overall survival of 922 gastric cancers were retrospectively analyzed. Proximal margin was divided into four groups (0-2.0, 2.1-4.0, 4.1-6.0, and >6.0cm). It indicated that the overall survival was improved with the increase of proximal margin. The proximal margin of 2.1-4.0cm was associated with a better overall survival for gastric cancers with solitary-type (T1 and T2 stages, N0 stage, tumor-node-metastasis stages I and II, tumor size <5cm, histological G1 and G2, and Bormann type I and II). Futhermore, proximal margin of 4.1-6.0cm was associated with a better overall survival for gastric cancers with infiltrative-type (T3 and T4 stages, N1 stage, tumor-node-metastasis stage III, tumor size 5cm, histological G3 and G4, and Bormann type III and IV). Univariate analysis revealed that T stage, N stage, tumor-node-metastasis stage, histological grade, Bormann type, carcinoembryonic antigen, carbohydrate antigen 199, extent of gastrectomy, tumor location, and proximal margin were significantly associated with overall survival. Multivariate analysis revealed that tumor-node-metastasis stage, histological grade, Bormann type, carcinoembryonic antigen, carbohydrate antigen 199, extent of gastrectomy, and proximal margin were independent prognostic factors for gastric cancers with radical gastrectomy. In conclusion, the proximal margin was an independent prognostic factor for gastric cancer and should be decided individually. Proximal margin of 2.1-4.0cm and 4.1-6.0cm were needed for patients with solitary-type and infiltrative-type, respectively.