The oncological safety in minimally invasive versus open distal pancreatectomy for pancreatic ductal adenocarcinoma: a systematic review and meta-analysis

The safety of minimally invasive distal pancreatectomy (MIDP) and open distal pancreatectomy (ODP) regarding oncological outcomes of pancreatic ductal adenocarcinoma (PDAC) remains inconclusive. Therefore, the aim of this study was to examine the oncological safety of MIDP and ODP for PDAC. Major databases including PubMed, Embase, Science Citation Index Expanded, and the Cochrane Library were searched for studies comparing outcomes in patients undergoing MIDP and ODP for PDAC from January 1994 to August 2018. In total, 11 retrospective comparative studies with 4829 patients (MIDP: 1076, ODP: 3753) were included. The primary outcome was long-term survival, including 3-year overall survival (OS) and 5-year OS. The 3-year OS (hazard ratio (HR): 1.03, 95% confidence interval (CI): 0.89, 1.21; P = 0.66) and 5-year OS (HR: 0.91, 95% CI: 0.65, 1.28; P = 0.59) showed no significant differences between the two groups. Furthermore, the positive surgical margin rate (weighted mean difference (WMD): 0.71, 95% CI: 0.56, 0.89, P = 0.003) was lower in the MIDP group. However, patients in the MIDP group had less intraoperative blood loss (WMD: −250.03, 95% CI: −359.68, −140.39; P < 0.00001), a shorter hospital stay (WMD: −2.76, 95% CI: −3.73, −1.78; P < 0.00001) and lower morbidity (OR: 0.57, 95% CI: 0.46, 0.71; P < 0.00001) and mortality (OR: 0.50, 95% CI: 0.31, 0.81, P = 0.005) than patients in the ODP group. The limited evidence suggested that MIDP might be safer with regard to oncological outcomes in PDAC patients. Therefore, future high-quality studies are needed to examine the oncological safety of MIDP.