Background: We conducted a retrospective study to evaluate clinical outcomes in patients with non-metastatic gastric adenocarcinoma (nmGA) treated at two high-volume academic institutions within the University of California (UC) system. Methods: Electronic Health Records and California Cancer Registry of demographic and clinical data were collected for pts with nmGA who underwent surgery with curative intent from 2010-2017. Medical chart reviews were conducted to validate outcomes. We used multivariate Cox regression to determine prognostic factors for cancer recurrence and overall survival. Results: Demographics of study cohort (n = 406): mean age 65 years; 71% male; 58% Caucasian, 26% Asian, 13% Latino. There was an even distribution between pts with locoregionally advanced (defined as pT4 or pN1+) vs. localized (pT1-3, pN0) disease. Tumor histology: 49% intestinal, 19% diffuse, 13% mixed, 19% unknown. Type of surgery: 27% open gastrectomy, 59% laparoscopic, 14% unknown. Multimodality therapy: 29% received perioperative systemic rx alone (48% adjuvant only, 52% neoadjuvant +/- adjuvant), 35% received perioperative systemic rx plus radiation (40% adjuvant only, 60% neoadjuvant +/- adjuvant), 36% underwent surgery only. With median f/u time after surgery of 5 years, 21% of pts developed cancer recurrence and 43% had died. Weight loss prior to diagnosis, locoregional stage, and positive resection margins were a/w recurrence (HR = 1.6-2.5, p < .05). Only locoregional stage was prognostic for worse survival (HR = 2.7, p < .0001). Positive resection margins were seen in 6% of pts and were a/w diffuse histology and tumor size > 4cm (odds ratio = 2.9-8.8, p < .02). Multimodality therapy was not a/w recurrence but was a/w longer survival after adjusting for stage (HR = 0.3, p < .0001). Addition of radiation to systemic rx did not confer further improvements in either recurrence or survival. Conclusions: This study highlights contemporary practice patterns for pts with nmGA and demonstrates a survival benefit with multimodality rx. Additional data are being gathered from other UC medical centers to confirm these findings and explore differences across institutions and ethnicities.