Clinical characteristics and outcomes of signet ring cell carcinoma of the stomach: A retrospective analysis of SEER database.

e16572 Background: Signet ring cell carcinoma (SRCC) of the stomach accounts for 8 to 30% of all gastric cancers, however the incidence has been rising. We performed a Surveillance, Epidemiology and End Results (SEER) database analysis to further characterize the biology and clinical aspects of this entity, in comparison to gastric adenocarcinoma (AC). Methods: Surveillance, Epidemiology and End Results (SEER) 18 database was used to obtain data on age, gender, ethnicity, survival, and tumor characteristics of 5,424 US patients diagnosed with gastric SRCC between 2012-2016 and these were compared to 40,657 patients with other gastric adenocarcinoma (AC) subtypes diagnosed during the same period. Results: The gender distribution of both types of cancer was similar with males making up 51.8% of gastric SRCC and 48.3% of gastric AC patients. Median age of diagnosis was 63 years for gastric SRCC as compared to 65 years for gastric AC patients. The age of diagnosis distribution for both types was similar with patient <40 years (7.2% versus 6.2% respectively), 40-60 years (34% versus 32% respectively), 60-80 years (44.6% versus 45.15% respectively) and at > 80 years (14.4% versus 16.6% respectively). Among the SRCC patients, 70.9 % were Caucasians, 15.5% were Asians/Pacific Islanders, and 11.6% were African-Americans. Amongst gastric AC patients, Caucasians made up 76% of the patients, while African-Americans made up 12.9% and Asian/Pacific Islanders made up 9.2 % of the patients. Median OS was 10 months for gastric SRCC compared to 24 months (p < 0.001) for gastric AC. Racial differences in overall survival (OS) was noted. The median OS in Caucasians, African-American, Asian/Pacific Islander, and Native American populations was 11,11,15,7 months respectively (p < 0.001). Conclusions: Gastric SRCC has significantly worse survival as compared to AC with median OS of 10 months vs 24 months. It is more common in patients with Asian/Pacific Islander ancestry as compared to gastric AC. There is a significant racial disparity in survival outcomes with significantly shorter survival in patients with Native american ancestry.