Mucinous subtype of gastric carcinoma is associated with lower number of lymph nodes examined

Background: Gastric cancer (GC) is one of the most common causes of cancer-related mortality. Gastric mucinous adenocarcinoma (GMA) is a rare histological type of GC. We analyzed the clinicopathological characteristics and prognostic value of GMA in GC. Methods: We utilized the National Cancer Institute's Surveillance, Epidemiology, and End Results dataset. Patient survival was analyzed using Kaplan-Meier survival curves, and comparisons were performed using the log-rank test. Multivariate survival analysis was adjusted by multiple clinicopathological factors. Results: GMA occurred more frequently in patients with higher pT and pN categories, and higher tumor-node-metastasis (TNM) stage. GMA was not an independent predictor of mortality (Cox's hazard ratio, 0.954; 95% CI, 0.847-1.075; P=0.439). We found that the number of lymph nodes examined (eLN) for patients with GMA were significantly lower than that for non-GMA (NGMA) patients (10.943 +/- 8.656 vs. 12.729 +/- 10.164, P<0.001). This result was confirmed by stratification analysis and logistic regression. Conclusions: GMA was frequently detected at an advanced stage, but there was no significant difference of survival between GMA and NGMA. The eLN of patients with GMA was significantly less than that for NGMA patients.