Lymph node ratio predicts prognosis in patients with surgically resected invasive pancreatic cystic neoplasms

BACKGROUND: In current days, the prevalence of pancreatic cystic neoplasms (PCN) is on the rise. Lymph node ratio (LNR) has emerged as a promising prognostic factor in pancreatic adenocarcinoma (PDAC). However, the prognostic value of LNR in patients with invasive PCN remains unknown. METHODS: We used Surveillance, Epidemiology, and End Results (SEER) database to retrieve the baseline characteristics and clinical tumor variables of patients diagnosed with PCN between 1988 and 2014. Survival analyses were performed using the Kaplan-Meier method. Univariate and multivariate analyses were performed to identify factors associated with patient prognosis. RESULTS: A total of 10,656 PCN cases were initially identified. Based on our exclusion criteria, our analyses included data from 1246 cases, of which 479 were patients with lymph node involvement. Patients with high LNR had shorter overall survival (OS) than patients with low LNR (median OS, 13 vs. 21 months; P=0). Our univariate and multivariate analyses identified LNR (P=0) and grade (P=0.010) as independent prognostic factors in patients with invasive PCN. CONCLUSIONS: Our findings suggest that LNR is a reliable, independent prognostic factor in patients with invasive PCN, strongly associated with OS and cancer-specific survival (CSS). LNR may represent a promising prognostic factor alternative to the AJCC (the American Joint Committee on Cancer) N stage in patients with node-positive PCN.