398 Histological Lymph Node Ratio and Long-Term Survival After Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma

Abstract

Abstract Background Pancreatoduodenectomy (PD) is recommended in fit patients with a resectable pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head. Early rates of recurrence are high and long-term survival is uncommon. This study aimed to investigate the association between histological lymph node ratio (LNR) and long-term survival. Method Data were extracted from the Recurrence After Whipple’s (RAW) study, a multicentre retrospective cohort study of outcomes of PD performed for pancreatic head malignancy (29 centres in 8 countries, n = 1484). Patients with histologically confirmed PDAC were identified, and five-year and overall survival rates were compared by LNR (number of positive resected nodes/total number of resected nodes). Analyses were performed using Fisher’s exact test, the Kaplan-Meier method, and the log-rank test. Results In total, 885 patients (59.6%) were found to have PDAC. Concerning LNR, 412 patients (48.3%) had a LNR <0.2 and 437 (51.5%) had a LNR ≥0.2 (unknown: 36 cases). Five-year survival was significantly higher in the former (34.0% vs 10.5%, p<0.0001). LNR was 0, >0.0-0.2 and >0.2 in 116 (17.5%), 261 (39.5%) and 284 (43.0%) patients, respectively (patients with missing data were excluded). Median survival was 646 (95% confidence interval: 526-766), 532 (483-581) and 438 (395-481) days, respectively (p<0.00001). Conclusions In our multicentre study of PD patients with confirmed PDAC, a histological LNR ≥0.2 was associated with reduced five-year survival. Patients with a LNR of >0.0-0.2 and >0.2 lived a median of 114 and 208 days less than those with a LNR of 0.0.