Effect of treatment center volume on outcomes in gastroenteropancreatic neuroendocrine tumor patients.

502Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are relatively rare tumors, where patients seek care at medical centers with varying levels of expertise. While treatment center volume is associated with better survival in multiple cancers, it remains unknown whether the same applies to GEP-NETs. The objective of this study was to assess the impact of center volume on GEP-NET treatment outcomes. Methods: We used the Surveillance, Epidemiology, and End Results (SEER) registry linked to Medicare claims data in this study. We included patients diagnosed between 1995-2010 who had no HMO coverage, participated in Medicare parts A and B, were older than 65 at diagnosis, had full tumor grade information, and had no secondary cancer. We used Medicare claims to identify the medical centers at which patients received GEP-NET treatment (surgery, chemotherapy, somatostatin analogues, or radiation therapy). Center volume was divided into tiers – low, medium, and high – based on the number of uniq...