Adoption of evidence-based novel therapies in the treatment of gastric cancer: A national observational study.

BACKGROUND: The adoption of novel and effective gastric cancer therapies into general clinical practice has crucial implications for patient outcomes. The current study explored trends in treatment use and overall survival in patients with gastric cancer in the United States.

METHODS: Patients with adenocarcinoma of the gastric cardia and noncardia were identified in the National Cancer Data Base between 2006 and 2014. Tumor stages were divided into early (IA), locally advanced (IB-IIIC), and metastatic (IV) stage. Treatment use was examined according to tumor stage and location. Time trend analyses of treatment use and overall survival were conducted.

RESULTS: A total of 89,098 patients with gastric adenocarcinoma were identified. In those with early-stage cancer, endoscopic treatment increased over time in patients with cardia and noncardia disease. In patients with locally advanced cardia disease, preoperative therapy use increased over time (2013-2014 [vs 2006-2008]: odds ratio [OR], 3.09; 95% confidence interval [95% CI], 2.80-3.41). In patients with locally advanced noncardia disease, the use of preoperative therapy also increased (2013-2014: OR, 3.32; 95% CI, 2.88-3.82) as did the use of perioperative therapy (2013-2014: OR, 4.21; 95% CI, 3.52-5.03) in lieu of postoperative treatment (2013-2014: OR, 0.66; 95% CI, 0.60-0.71). In patients with metastatic disease, approximately 34% of patients with cardia and 40% of patients with noncardia cancer did not receive treatment. Stage-specific and location-specific overall survival was found to improve over the study period.

CONCLUSIONS: Practice patterns for the treatment of gastric cancer in the United States reflect the increased adoption of evidence-based therapies, including endoscopic resection of early-stage cancer and preoperative therapy for patients with locally advanced disease. Treatment for metastatic disease remains markedly underused. Cancer 2018;124:1122-31. © 2017 American Cancer Society.