Macroscopic Serosal Classification as a Prognostic Index in Radically Resected Stage pT3-pT4b Gastric Cancer.

Abstract

Macroscopic serosal classification (MSC) is an important clinicopathologic index of gastric cancer (GC). To investigate the prognostic significance of MSC status in patients with radically resected stage pT3-pT4b GC, we examined the relationship between MSC type and pT stage. Clinicopathologic and survival data of 1613 patients with stage pT3-pT4b GC were studied retrospectively, in the aftermath of radical surgery. MSC types, including reactive, nodular, tendonoid, and color-diffused type, correlated significantly with overall survival (OS) in this cohort, but prognosis was similar for all stages of color-diffused type GC. We proposed a revised pT stage in which color-diffused type cancers at pT3 or pT4a stage were reclassified into pT4b stage. In two-step multivariate analysis, revised pT stage (stage pT4b for all color-diffused types) proved more suitable for determining prognosis, surpassing both Union for International Cancer Control/American Joint Committee on Cancer pT stage and MSC type as an independent prognostic index. MSC type is a significant and independent prognostic index of OS in patients with radically resected stage pT3-pT4b GC. For prognostic purposes, tumors of color-diffused type at pT3 or pT4a stage should be considered stage pT4b disease.