Recurrence patterns of pancreatic cancer after pancreatoduodenectomy: systematic review and a single-centre retrospective study

Background: Positive margins in pancreatoduodenectomy (PD) for pancreatic cancer, specifically the superior mesenteric artery (SMA) margin, are associated with worse outcomes. Local therapies targeting these margins could impact on recurrence. This study analysed recurrence-patterns to identify whether strategies to control local disease could have a meaningful impact.Methods: (I) Systematic review to define recurrence patterns and resection margin status. (II) Additional retrospective study of PD performed at our centre.Results: In the systematic review, 23/617 evaluated studies were included (n = 3815). Local recurrence was observed in 7-69%. SMA margin (6 studies) was positive in 15-35%. In the retrospective study (n = 204), local recurrence was more frequently observed with a positive SMA margin (66 vs.45%; p = 0.005). Furthermore, in a multivariate cox-proportional hazard model, only a positive SMA margin was associated with disease recurrence (HR 1.615; 95%CI 1.127-2.315; p = 0.009). Interestingly, median overall survival was 20 months and similar for patients who developed local only, metastases only or simultaneous recurrence (p = 0.124).Conclusion: Local recurrence of pancreatic cancer is common and associated with similar mortality rates as those who present with simultaneous or metastatic recurrence. Involvement of the SMA margin is an independent predictor for disease progression and should be the target of future adjuvant local therapies.