Meta-analysis of recurrence pattern after resection for pancreatic cancer

Background Initial recurrence mapping of resected pancreatic ductal adenocarcinoma (PDAC) could help in stratifying patient subpopulations for optimal postoperative follow-up. The aim of this systematic review and meta-analysis was to investigate the initial recurrence patterns of PDAC and to correlate them with clinicopathological factors. Methods MEDLINE and Web of Science databases were searched systematically for studies reporting first recurrence patterns after PDAC resection. Data were extracted from the studies selected for inclusion. Pooled odds ratios (ORs) and 95 per cent confidence intervals were calculated to determine the clinicopathological factors related to the recurrence sites. The weighted average of median overall survival was calculated. Results Eighty-nine studies with 17 313 patients undergoing PDAC resection were included. The weighted median rates of initial recurrence were 20 center dot 8 per cent for locoregional sites, 26 center dot 5 per cent for liver, 11 center dot 4 per cent for lung and 13 center dot 5 per cent for peritoneal dissemination. The weighted median overall survival times were 19 center dot 8 months for locoregional recurrence, 15 center dot 0 months for liver recurrence, 30 center dot 4 months for lung recurrence and 14 center dot 1 months for peritoneal dissemination. Meta-analysis revealed that R1 (direct) resection (OR 2 center dot 21, 95 per cent c.i. 1 center dot 12 to 4 center dot 35), perineural invasion (OR 5 center dot 19, 2 center dot 79 to 9 center dot 64) and positive peritoneal lavage cytology (OR 5 center dot 29, 3 center dot 03 to 9 center dot 25) were significantly associated with peritoneal dissemination as initial recurrence site. Low grade of tumour differentiation was significantly associated with liver recurrence (OR 4 center dot 15, 1 center dot 71 to 10 center dot 07). Conclusion Risk factors for recurrence patterns after surgery could be considered for specific surveillance and treatments for patients with pancreatic cancer.