Prognostic Value of Gastric Signet Ring Cell Carcinoma: a Population-Based Propensity Score-Matched Analysis

The prognostic value of signet ring cell carcinoma in gastric cancer is still a point of discussion. This study aims to assess the impact of signet ring cell carcinoma on long-term survival of gastric cancer patients following resection. Patients undergoing surgical resection for gastric cancer between 2010 and 2015 were identified in the Surveillance, Epidemiology, and End Results database. Propensity score-matching analysis was utilized to assess the overall survival and disease-specific survival. Among the 6051 included patients, 1246 (20.6%) had signet ring cell carcinoma and 4805 (79.4%) had non-signet ring cell carcinoma. Both the 5-year overall survival and disease-specific survival rates in signet ring cell carcinoma group were significantly worse than those in non-signet ring cell carcinoma group (41.1 vs. 44.1%, P = 0.012; 43.9 vs. 49.8%, P <0.001). After matching, 1109 pairs were selected, and it was found that neither overall survival nor disease-specific survival was significantly different between the two groups. At multivariate analysis, signet ring cell carcinoma did not influence overall survival (hazard ratio = 1.05, 95% confidence interval 0.93-1.18, P= 0.4661) and disease-specific survival (hazard ratio = 1.01, 95% confidence interval 0.89-1.14, P= 0.907). When patients were stratified by tumor stage, signet ring cell carcinoma was still found to be not associated with decreased survival outcomes in both early and advanced gastric cancer groups. This study demonstrates that signet ring cell carcinoma does not negatively impact survival of gastric cancer patients, regardless of the disease stage.