Systematic review of prospective studies focused on regionalization of care in surgical oncology

To perform a systematic review of studies prospectively analyzing the impact of regionalization of complex surgical oncology care on patient outcomes. High volume care of complex surgical oncology patients has been repeatedly associated with improved outcomes. Most studies, however, are retrospective and have not prospectively accounted for confounders such as financial ability and social support. Four electronic databases (Ovid MEDLINE®, Ovid EMBASE, Cochrane Library (Wiley), and EBSCHOHost) were searched from inception until August 25, 2018. Two authors independently reviewed 5887 references, with a third independent reviewer acting as arbitrator when needed. Data extracted from 11 articles that met inclusion criteria. Risk of bias assessments conducted using MINORS criteria for the non-randomized, observational studies, and the Cochrane tool for the randomized-controlled trial. Of the 11 studies selected, we found 7 historically-controlled trials, two retrospective cohort studies with prospective data collection, one prospective study, and one randomized-controlled trial. 73% of studies were from Northern Europe, 18% from Ontario, Canada, and 9% from England. Pancreatic surgery accounted for 36% of studies, followed by gynecologic oncology (27%), thoracic surgery (18%), and dermatologic surgery (9%). The studies reported varying outcome parameters, but all showed improvement post-regionalization. Included studies featured poor-to-fair risk of bias. 11 studies indicated improved outcomes following regionalization of surgical oncology, but most exhibit poor methodological rigor. Prospective evidence for the regionalization of surgical oncology is lacking. More research addressing patient access to care and specialist availability is needed to understand the shortcomings of centralization.