Impact On Gemcitabine Plus Cisplatin In Unresectable Hilar Cholangiocarcinoma Patients According To Effective Biliary Drainage: A Multicenter Study.

e15658 Background: Hilar cholangiocarcinoma (HC) is known to have a poor prognosis due to cholangitis and lack of effective chemotherapeutic regimen. Since 2010, gemcitabine plus cisplatin (GP) is recommended as first-line chemotherapy in cholangiocarcinoma. However, it is still unclear whether GP is effective on HC. We aimed to evaluate the impact on GP in unresectable HC patients according to effective biliary drainage (EBD). Methods: From 2010 to 2016, 112 patients with unresectable HC confirmed by biopsy at three tertiary referral hospitals in Korea were enrolled. 38 patients received GP [cisplatin (25 mg per square meter of body-surface area) followed by gemcitabine (1000 mg per square meter), each administered on days 1 and 8, every 3 weeks]. 74 patients received best supportive care (BSC). The EBD group was defined as a total bilirubin decrease of less than 2 mg/dl within 2 weeks after the first drainage procedure or 50% reduction than pre-procedure total bilirubin. Overall survival (OS) was evaluated in GP group and BSC group according to EBD achieved using the Kaplan–Meier survival curve and the log-rank test. Results: When compared with the BSC group (n = 74), the GP group (n = 38) obtained a benefit in OS (median OS, 6.14 vs 12.7 months, p < 0.001). Moreover, patients with EBD experienced significantly longer OS compared with ineffective biliary drainage (IEBD) patients (median OS, 8.03 vs 5.01 months, p < 0.005). GP chemotherapy was beneficial for OS in IEBD group (p < 0.001) as well as in EBD group (p < 0.005). In the multivariate analysis, GP chemotherapy (HR 0.33, 95% CI 0.21–0.52, p < 0.001), EBD (HR 0.60, 95% CI 0.40–0.91, p < 0.001) and 2 more metastatic site (HR 3.21, 95% CI 1.66–6.18, p < 0.001) were significant prognostic factors. Conclusions: GP chemotherapy provides longer survival in HC, regardless of effective or ineffective biliary drainage.