Clinical Outcomes Following Regionalization of Gastric Cancer Care in a US Integrated Health Care System

Abstract

PURPOSE In 2016, Kaiser Permanente Northern California regionalized gastric cancer care, introducing a regional comprehensive multidisciplinary care team, standardizing staging and chemotherapy, and implementing laparoscopic gastrectomy and D2 lymphadenectomy for patients eligible for curative-intent surgery. This study evaluated the effect of regionalization on outcomes. METHODS The retrospective cohort study included gastric cancer cases diagnosed from January 2010 to May 2018. Information was obtained from the electronic medical record, cancer registry, state vital statistics, and chart review. Overall survival was compared in patients with all stages of disease, stage I-III disease, and curative-intent gastrectomy patients using annual inception cohorts. For the latter, the surgical approach and surgical outcomes were also compared. RESULTS Among 1,429 eligible patients with gastric cancer with all stages of disease, one third were treated after regionalization, 650 had stage I-III disease, and 394 underwent curative-intent surgery. Among surgical patients, neoadjuvant chemotherapy utilization increased from 35% to 66% ( P < .0001), laparoscopic gastrectomy increased from 18% to 92% ( P < .0001), and D2 lymphadenectomy increased from 2% to 80% ( P < .0001). Dissection of ≥ 15 lymph nodes increased from 61% to 95% ( P < .0001). Surgical complication rates did not appear to increase after regionalization. Length of hospitalization decreased from 7 to 3 days ( P < .001). Overall survival at 2 years was as follows: all stages, 32.8% pre and 37.3% post ( P = .20); stage I-III cases with or without surgery, 55.6% and 61.1%, respectively ( P = .25); and among surgery patients, 72.7% and 85.5%, respectively ( P < .03). CONCLUSION Regionalization of gastric cancer care within an integrated system allowed comprehensive multidisciplinary care, conversion to laparoscopic gastrectomy and D2 lymphadenectomy, increased overall survival among surgery patients, and no increase in surgical complications.