Impact of Remnant Carcinoma in Situ at the Ductal Stump on Long-Term Outcomes in Patients with Distal Cholangiocarcinoma.

Background: The management of positive ductal margins with carcinoma in situ (R1-CIS) after resection is controversial. The aim of this study was to evaluate the impact of R1-CIS on survival in patients who underwent resection for distal cholangiocarcinoma.

Methods: We enrolled 121 consecutive patients with distal cholangiocarcinoma. Poor prognostic factors were investigated by multivariable analysis, and we performed a stratified analysis to evaluate the impact of R1-CIS on survival in patients with or without prognostic factors.

Results: Multivariable analysis identified node-positive status as the prognostic factor (P = 0.003). Stratified by lymph node status, overall survival (OS) in the R0 group was significantly better than that in the R1-CIS group in node-negative patients (57.1% vs 30.0%; P < 0.050). Although OS was comparable between the two groups in node-positive patients (5-year OS: 22.2% vs 20.0%, respectively; P = not significant). Furthermore, OS in patients in whom R0 was achieved by additional resection was significantly better than that in patients with R1-CIS (5-year OS: 66.7% vs 30.0%, respectively; P < 0.050).

Conclusions: Remnant CIS is associated with a poor prognosis in patients with node-negative distal cholangiocarcinoma. Every effort should be made to achieve negative bile duct margins.