Clinical impact of additional therapy for residual pancreatic cancer

This study aimed to explore the prognostic significance of the resection margin (R) status of pancreatic ductal adenocarcinoma (PDAC) patients receiving neoadjuvant therapy (NAT) or adjuvant chemotherapy (AC).

We retrospectively reviewed 427 consecutive patients, and the overall survival (OS) and disease-free survival (DFS) were analyzed based on the R status by a propensity score analysis (PSA).

The R0 ratio of the NAT (+) group was significantly higher than that of the NAT (-) group (97.2% vs. 69.6%, P < 0.0001). Local recurrence was well controlled in the NAT (+) group compared to the NAT (-) group (15.3% vs. 34.1%, P = 0.0013). The PSA revealed no significant survival difference between R0 and R1 resection among those treated with AC (median survival time [MST]: 43.0 vs. 33.3 months, matching hazard ratio [HR]: 1.212, P = 0.5708). Furthermore, the DFS in R0 and R1 resection followed by AC was identical (MST: 20.6 vs. 17.7 months, matching HR: 1.020, P = 0.9482).

NAT was a significant predictor of R0 resection. When patients completed AC, there were no marked differences in the OS or DFS between R0 and R1 resection. Our results demonstrated that the clinical impact of the R1 status has waned in the current era of PDAC management.