Role of Intraoperative Assessment of Proximal Bile Duct Margin Status and Additional Resection of Perihilar Cholangiocarcinoma: Can Local Clearance Trump Tumor Biology? A Retrospective Cohort Study.

Background: The aim of this study was to evaluate the clinical implications of the proximal bile duct margin status in resection of perihilar cholangiocarcinoma (PHCC). Intraoperative frozen section (IFS) analysis to assess the bile duct margin status is commonly used during PHCC resection. However, the impact of additional resection after obtaining a positive margin on the long-term outcome remains unclear.

Patients And Methods: Among the 257 patients who underwent PHCC resection, 190 patients with a negative distal margin were included and analyzed. IFS analysis of the proximal bile duct margin was performed in all patients. A positive margin was defined by the presence of either invasive cancer, or carcinoma, in situ.

Results: IFS analysis revealed an initial positive margin in 69 (36%) patients. Among 20 patients who underwent re-resection, only 11 patients achieved a negative margin (secondary R0). An initial positive margin was associated with poor long-term outcomes: recurrence-free survival (RFS) and overall survival (OS) were 16 and 25 months for patients with an initial positive margin, but 47 and 63 months for patients with an initial negative margin, respectively (p < 0.0001). In contrast, there was no difference in RFS or OS between patients with a secondary R0 margin, and those with a final R1 margin (14 vs. 16 months for RFS, p = 0.98, and 23 versus 25 months for OS, p = 0.63, respectively).

Conclusion: An IFS-positive proximal hepatic duct margin dictates poor long-term outcomes for patients with resectable PHCC. Additional resection has minimal impact on survival, even when negative margin is achieved.