Impact of Resection Margins and Adjuvant Therapy on Survival Outcomes in Lymph Node-Negative Distal Cholangiocarcinoma.

The prognostic value of the resection margin (RM) status and the efficacy of adjuvant therapy (AT) in distal cholangiocarcinoma (CCC) are unclear. RM status appears particularly impactful in lymph node-negative distal CCC, representing early-stage disease. The prognostic value of RM status was investigated, and subpopulations of patients with lymph node-negative distal CCC who might benefit from AT were identified. Overall, 139 patients with distal CCC who underwent surgical resection between March 2006 and December 2023 were analyzed. RM status was categorized as wide (>5 mm) in 65 patients (46.8%), close (≤5 mm) in 32 patients (23.0%), or positive in 42 patients (30.2%). AT was administered to 48 patients (34.5%). Patients with close or positive RMs achieved significantly lower locoregional control (LRC) than those with wide RMs. However, overall survival (OS) did not differ across the three RM groups. The impact of RM status was more evident in patients not receiving AT. Patients with wide RMs exhibited better 3-year LRC, progression-free survival (PFS), and OS rates (79.0%, 66.5%, and 69.1%, respectively) than those with close (21.7%, 15.7%, and 34.4%) or positive RMs (44.3%, 25.3%, and 50.2%, respectively). No significant differences were found between close and positive RM groups. AT appears to have improved LRC and PFS in patients with close or positive RMs but not in those with wide RMs. Close RMs were associated with poor outcomes comparable to those with positive RMs. These results indicate that achieving adequate RM width is crucial for improving survival. Moreover, AT may improve survival when adequate RMs cannot be achieved. Nonetheless, larger studies are needed to validate these findings.