Improvement of T stage precision by integration of surgical and pathological staging in radically resected stage pT3-pT4b gastric cancer.

BACKGROUND: Both surgical TNM (sTNM) and pathological TNM (pTNM) staging are important clinicopathologic indexes of gastric cancer (GC). However, surgeons and pathologists might assess tumor depth differently in the same patient. To investigate the prognostic significance of sTNM status in patients with radically resected stage pT3-pT4b GC, we examined the relationship between sTNM and pTNM. METHODS: Clinicopathologic and survival data of 1289 patients with stage pT3-pT4b GC were studied retrospectively, in the aftermath of radical surgery. RESULTS: The unconformity for assessing tumor invasion depth were frequently exhibited between sT and pT staging. Comparison of 5-year OS among them, no significant differences were observed (pT3/sT3 vs pT3/sT4a, p=0.962; pT4a/sT4b vs pT4b/sT4b, p=0.508). Also, pT3/sT4b, pT4a/sT3 and pT4a/sT4a were homogeneity in prognosis. We proposed a revised pT stage in which surgical macroscopic T4b (sT4b) was incorporated into the pT stage, namely, patients in the pT3 stage with sT4b cancers were reclassified as being in the r-pT4a stage; patients in the pT4a stage with sT4b cancers were reclassified as being in the r-pT4b stage. In two-step multivariate analysis, revised pT stage proved more suitable for determining prognosis, surpassing both UICC/AJCC pT stage and sT stage as an independent prognostic index. CONCLUSIONS: Surgical T stage is a significant and independent prognostic index of overall survival (OS) in patients with radically resected advanced GC. Patients in the pT3/4a stage with sT4b cancers, are potentially underestimated, and should be considered higher stage in terms of prognostic.

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

BACKGROUND: 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. METHODS: Clinicopathologic and survival data of 1613 patients with stage pT3-pT4b GC were studied retrospectively, in the aftermath of radical surgery. RESULTS: 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. CONCLUSIONS: 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.