Long-term Outcomes Following Resection of Adenocarcinoma Arising from Intraductal Papillary Mucinous Neoplasm (A-IPMN) Versus Pancreatic Ductal Adenocarcinoma (PDAC): A Propensity-score Matched Analysis

OBJECTIVE: The aim of the present study was to compare long-term postresection oncological outcomes between adenocarcinoma arising from intraductal papillary mucinous neoplasms (A-IPMN) and pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Knowledge of long-term oncological outcomes (e.g. recurrence and survival) comparing A-IPMN and PDAC is scarce. METHODS: Patients undergoing pancreatic resection (2010-2020) for A-IPMN were identified retrospectively from 18 academic pancreatic centers and compared with PDAC patients from the same time period. Propensity-score matching was performed, and survival and recurrence were compared between A-IPMN and PDAC. RESULTS: In all, 459 A-IPMN patients (median age,70; M:F,250:209) were compared with 476 PDAC patients (median age,69; M:F,262:214). A-IPMN patients had lower T-stage, lymphovascular invasion (51.4% vs. 75.6%), perineural invasion (55.8% vs. 71.2%), lymph node positivity (47.3% vs. 72.3%) and R1 resection (38.6% vs. 56.3%) compared with PDAC ( P <0.001). The median survival and time-to-recurrence for A-IPMN versus PDAC were 39.0 versus 19.5 months ( P <0.001) and 33.1 versus 14.8 months ( P <0.001), respectively (median follow-up, 78 vs. 73 months). Ten-year overall survival for A-IPMN was 34.6% (27/78) and PDAC was 9% (6/67). A-IPMN had higher rates of peritoneal (23.0% vs. 9.1%, P <0.001) and lung recurrence (27.8% vs. 15.6%, P <0.001) but lower rates of locoregional recurrence (39.7% vs. 57.8%; P <0.001). The matched analysis demonstrated inferior overall survival (P=0.005), inferior disease-free survival ( P =0.003), and higher locoregional recurrence ( P <0.001) in PDAC compared to A-IPMN but no significant difference in systemic recurrence rates ( P =0.695). CONCLUSIONS: PDACs have inferior survival and higher recurrence rates compared with A-IPMN in matched cohorts. Locoregional recurrence is higher in PDAC, but systemic recurrence rates are comparable and constituted by their own distinctive site-specific recurrence patterns.