Survival outcome after stereotactic body radiotherapy for locally advanced and borderline resectable pancreatic cancer: A systematic review and meta-analysis.

Background: Some studies reported stereotactic body radiotherapy (SBRT) has demonstrated superior therapeutic results than conventional radiotherapy. Nevertheless, this statement is controversial and the trial attempting to prove this is underway. We conducted this systemic review and meta-analysis aiming to combine the latest and most complete information about the survival outcomes and toxicities following SBRT for locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC).

Methods: Items involving SBRT and pancreatic cancer were searched in PubMed, EMBASE, Cochrane Library, SCOPUS and Web of Science. Median overall survival (OS), 1/2/3-year OS, median progression-free survival (PFS), 1/2/3-year PFS and incidence of grade 3-5 toxicities were the endpoints of interest in this meta-analysis. These endpoint proportions were pooled and analyzed using R.

Results: For the LAPC series, the median OS was 14.1 months; pooled 1/2/3-year OS rates were 57%, 19% and 10%, respectively; the median PFS was 10 months; pooled 1/2/3-year PFS rates were 36%, 12% and 4%; pooled incidence rates of acute gastrointestinal (GI), acute hematologic and late GI toxicity (grade≥3) were 2%, 4% and 8%. For the BRPC series, the median OS was 17.5 months; pooled 1/2-year OS rates were 75% and 29%; the median PFS was 12.2 months; pooled 1/2-year PFS rates were 48% and 18%; the incidence rates of toxicity (grade ≥ 3) were all 0%.

Conclusions: Our meta-analysis based on published results of OS, PFS and incidence rates of toxicity demonstrated that SBRT does not show desirable therapeutic result than the standard therapies for LAPC and BRPC.