Predictive risk factors for peritoneal recurrence after pancreatic cancer resection and strategies for its prevention

Purpose: To evaluate the risk factors for peritoneal recurrence (PR) of pancreatic adenocarcinoma and to discuss the appropriate management strategies. Methods: We reviewed the medical records of 236 patients who underwent pancreatectomy for pancreatic adenocarcinoma. We then compared the clinicopathological characteristics of patients with vs. those without PR. The independent risk factors for PR were defined using the Cox proportional hazards regression model. Results: The median survival of patients with PR was 13.3 months after surgical treatment. The PR group had a significantly higher incidence of portal vein resection, longer operative time (≥648 min), greater blood loss (≥2179 mL), blood transfusion, tumor size, portal vein invasion, artery invasion, pancreatic nerve plexus invasion, and histological grade. Multivariate analysis revealed that excessive blood loss (≥2179 mL; P = 0.010), artery invasion (P = 0.025), pancreatic nerve plexus invasion (P = 0.001), and histological grade 3 (P = 0.011) were independent risk factors for PR. Excessive blood loss was also strongly related to tumor size (P = 0.018). Conclusions: Local invasion and tumor size-related factors suggested the possibility of intraoperative dissemination at the time of tumor resection. Preoperative treatment and an operative procedure to prevent tumor exposure may help prevent PR.