Characterization of HER2 testing and treatment patterns among patients with gastric cancer in the United States using the Oncology Services Comprehensive Electronic Records (OSCER) database.

36 Background: There is a paucity of data related to HER2 testing and treatment patterns among gastric cancer patients in a real-world setting. Our primary objectives were to (1) identify the proportion of gastric cancer patients who received HER2 testing, the proportion of patients with HER2+ve tumors, and the proportion of HER2+ve patients who received trastuzumab; (2) describe treatment patterns among gastric cancer patients, including the proportion of patients who received surgery and/or radiation with chemotherapy; (3) identify the proportion of patients who received singlet, doublet, or triplet chemotherapy treatments and specific first- and second-line regimens. Methods: The study participants were randomly selected to undergo a detailed chart review from a source population of patients included in the OSCER database who were diagnosed with gastric cancer from 2009 to 2013. OSCER is a data warehouse of electronic medical records from 565 community and hospital-affiliated oncology clinics in the U....