A phase II study of gemcitabine as adjuvant treatment for biliary tract cancer after surgical resection.

Abstract

330 Background: The role of adjuvant therapy following resection of biliary tract cancer (BTC) remains unclear. We therefore evaluated the feasibility and toxicity of adjuvant gemcitabine in patients with BTC. Methods: This clinical phase II study was an open-label, single center, single-arm study. Within 8 weeks after gross complete resection of BTC, patents received gemcitabine 1000 mg/m2as an intravenous 30-min infusion on day 1, 8, and 15 for every 28 days. Intratumoral expression of cytidine deaminase (CDA), human equilibrative transporter-1 (hENT1), deoxycytidine kinase (dCK) and ribonucleotide reductase subunit 1 (RRM1) was measured by immunohistochemistry and eight SNPs in the CDA, hENT1, dCK, hCNT3 and RRM1 genes were evaluated. The relationship of each with patients’ clinical outcomes was assessed. Results: From January 2010 to July 2014, a total of 72 BTC patients (26 with gallbladder cancer, 33 with extrahepatic cholangiocarcinoma, and 13 with intrahepatic cholangiocarcinoma) were enrolled. At a median follow-up was 38.09 months (range: 4.14-68.29), 2-year recur- free survival (RFS) was 43% (95% CI, 33% to 57%). The most common grade 3 and 4 toxicity was neutropenia, which occurred in 8 patients (11%). There was one treatment-related death from pneumonitis. The Cox proportion hazard model was performed with the following nine variables; gross type, degree of tumor differentiation. pathologic T factor, N stage, vascular invasion, perineural invasion, lymphatic invasion, dosage, and each protein expression. In the multivariable model, DCK expression, vascular invasion, and lymph node metastasis, were significantly associated with RFS. None of the tested SNPs was significantly associated with RFS or with any hematologic or non-hematologic toxicity. Conclusions: Although the primary hypothesis of this study, defined as a 2-year RFS of 60%, was not met, intratumoral DCK expression was significantly associated with RFS in patients with resected BTC treated with postoperative gemcitabine chemotherapy. Future randomized controlled trials are warranted. Clinical trial information: NCT01043172.