The Impact of Surgical Margin Status on Long-Term Outcome After Resection for Intrahepatic Cholangiocarcinoma.

Background: The influence of margin status on long-term outcome of patients undergoing liver resection for intrahepatic cholangiocarcinoma (ICC) remains controversial. We sought to study the impact of surgical tumor margin status on recurrence-free survival (RFS) and overall survival (OS) of patients undergoing resection for ICC.

Methods: From a multi-institutional database, 583 patients who underwent hepatic resection for ICC were identified. Demographics data, operative details, pathologic margin status, and long-term outcomes were collected and analyzed.

Results: Margin status was positive (R1) in 95 (17.8 %) patients; among patients who underwent an R0 resection (80.9 %), margin width was negative by 1-4 mm in 166 (31.0 %) patients, 5-9 mm in 100 (18.7 %) patients, and ≥1 cm in 174 (32.5 %) patients. Overall, 379 (65.0 %) patients had a recurrence: 61.5 % intrahepatic, 13.5 % extrahepatic, and 25.0 % both intra- and extrahepatic. Median and 5-year RFS and OS was 10.0 months and 9.2 %, and 26.4 months and 23.0 %, respectively. Patients who had an R1 resection had a higher risk of recurrence (hazard ratio [HR] 1.61, 95 % CI 1.15-2.27; p = 0.01) and shorter OS (HR 1.54, 95 % CI 1.12-2.11). Among patients with an R0 resection, margin width was also associated with RFS (1-4 mm: HR 1.32, 95 % CI 0.98-1.78 vs. 5-9 mm: HR 1.21, 95 % CI 0.89-1.66) and OS (1-4 mm: HR 1.95, 95 % CI 0.45-2.63 vs. 5-9 mm: HR 1.21, 95 % CI 0.88-1.68) (referent ≥1 cm; both p ≤ 0.002). Margin status and width remain independently associated with RFS and OS on multivariable analyses.

Conclusions: For patients undergoing resection of ICC, R1 margin status was associated with an inferior long-term outcome. Moreover, there was an incremental worsening RFS and OS as margin width decreased.