Outcome of head compared to body and tail pancreatic cancer: a systematic review and meta-analysis of 93 studies.

Background: Even when resectable pancreatic cancer (PC) is associated with a dismal prognosis. Initial presentation varies according with primary tumor location. Aim of this systematic review and meta-analysis was to evaluate the prognosis associated with site (head versus body/tail) in patients with PC.

Methods: We searched PubMed, Cochrane Library, SCOPUS, Web of Science, EMBASE, Google Scholar, LILACS, and CINAHL databases from inception to March 2018. Studies reporting information on the independent prognostic role of site in PC and comparing overall survival (OS) in head versus body/tail tumors were selected. Data were aggregated using hazard ratios (HRs) for OS of head versus body/tail PC according to fixed- or random-effect model.

Results: A total of 93 studies including 254,429 patients were identified. Long-term prognosis of head was better than body/tail cancers (HR =0.96, 95% CI: 0.92-0.99; P=0.02). A pooled HR of 0.95 (95% CI: 0.92-0.99, P=0.02) from multivariate analysis only (n=77 publications) showed that head site was an independent prognostic factor for survival.

Conclusions: Primary tumor location in the head of the pancreas at the time of diagnosis is a predictor of better survival. Such indicator should be acknowledged when designing future studies, in particular in the operable and neoadjuvant setting.