Comparison of clinicopathologic profiles and prognosis of gastric cancer in the upper, middle and lower third of the stomach: A retrospective cohort study

Gastric cancer (GC) is the fourth most common cancer in the world and the second most common cancer in China. The aim of this study was to investigate the clinicopathologic profiles and prognosis of GC in the upper third (UT), middle third (MT) and low third (LT) of the stomach. Five hundred and forty-two patients with GC resected between January 2010 and January 2014 were retrospectively studied and divided in 3 groups according to cancer location: upper third gastric cancer (UTGC) (n = 62); MTGC (n = 131) and LTGC (n = 349). Clinical and pathological parameters including gender, age, tumor size, macroscopic types, histological types, depth of invasion, lymph node metastasis, venous infiltration and lymph embolism were compared among groups. Overall survival (OS) was calculated based on the aforementioned parameters. Univariate and multivariate survival was analyzed and Cox regression was conducted for each location. The prognostic accuracy was determined using receiver operating characteristic curve analysis. Patients with UTGC was similar to those with MTGC and both were distinct from those with LTGC based on the tumor size, macroscopic types, depth of invasion and 5-year OS. Patients with MTGC were similar to those with LTGC and distinct from UTGC patients based on gender. 5-year OS were lower for patients with UTGC than those with LTGC (P = .001) and were comparable between MTGC and LTGC. No significant differences in 5-year OS were observed between UTGC and MTGC. Cox regression revealed that macroscopic types, depth of invasion and lymph node metastasis were the independent prognostic factors for GC patients regardless of locations. Receiver operating characteristic curve analysis revealed that macroscopic types, depth of invasion and lymph node metastasis were the significantly effective prognosis for the 5-year OS in GC patients regardless of locations. Our results showed that UTGC is distinct from LTGC whereas MTGC shares some characteristics from both UTGC and LTGC.