Abstract
BACKGROUND: An adequate number of retrieved lymph nodes (rLNs) are crucial for accurate N-stage assessment; however, the optimal number of rLNs for duodenal adenocarcinoma remains undefined. This study aims to determine the minimum number of rLNs in node-negative patients. MATERIALS AND METHODS: The study cohorts were derived from the Wuhan Union Hospital (WUH, n = 237) and Surveillance, Epidemiology, and End Results (SEER, n = 1045) databases. The surv-cutpoint function was used to identify the optimal cutoff values (OCVs). Propensity score matching and proportional hazards model were utilized to reduce selection bias and control for confounders. RESULTS: The WUH cohort included 181 N0 and 56 N1 [one positive lymph node (LN) only] patients, while the SEER cohort comprised 761 N0 and 284 N1 patients. In our cohort, the OCVs for rLNs in N0 and N1 patients were 12 and 15, respectively, with values exceeding the OCV considered a sufficient number of rLNs. Findings from both cohorts indicated that adequate rLNs correlated with a better prognosis than limited rLNs, regardless of the N0 or N1 group. Moreover, prognosis was similar between the N0-limited and N1-adequate groups, potentially due to staged migration. Survival curves revealed that the T4N0-limited group could benefit from chemoradiotherapy, whereas the T4N0-adequate group did not. CONCLUSIONS: It is essential for N0 patients to have at least 13 LNs, while N1 patients require a minimum of 16 LNs. Having fewer than the recommended rLNs is considered an independent prognostic risk factor.