Abstract Objectives:Despite intensive chemotherapy for biliary tract cancer (BTC), the outcome is not enough. Dendritic cells are the powerful antigen-presenting cells that have attracted attention from the efficacy of DC-based immunotherapy against many types of cancers. The objective of this study was to clarify the safety and efficacy of dendritic cell therapy for BTC.Methods: This retrospective study selected patients who underwent DC-based vaccine for BTC between May of 2009 and February of 2012. The safety of this treatment, median survival time (MST), 1-year survival rate, objective response rate (ORR), and disease control rate (DCR) were evaluated. The univariate and multivariate analyses were performed to identify the efficacy of DC by a Cox proportional hazards analysis.Results:Twenty-seven patients were selected for the study. The patients, and all but one patient had previous therapy, 13 patients had undergone prior surgical resection, and 21 patients went on to receive chemotherapy. No serious treatment-related adverse events were observed during the study period. One-year survival rate from 1st vaccination was 22 % and from the initial diagnosis was 67%. The MST from 1st vaccination and from the initial diagnosis were 8.2 months and 18.5 months, respectively. DCR and ORR were 37% and 11%,respectively. None of 27 patients showed complete response (CR), but we have found out 3 cases of partial responses (PR) and 7 cases of stable disease (SD).Furthermore, LDH, CRP, DTH, Performance Status (PS), combination with lymphokine-activated killer, chemotherapy were found to be statistically significant independent risk factors in multivariate analysis.Conclusion: DC-based immunotherapy for BTC was safe and prolonged the MST of the patients with BTC compared to chemotherapy alone,comparing the result from UK ABC-02 trial. DC-based immunotherapy for BTC may another option for BTC patient who has no chance for curative surgery. Citation Format: Masanori Kobayashi, Tomoyo Sakabe, Mitsugu Tanii, Hirofumi Abe, Hedenori Takahashi, Shun-ichi Tsujitani, Shigetaka Shimodaira, Yoshikazu Yonemitsu, Masato Okamoto, Masaki Nagaya. Dendritic cell-based immunotherapy targeting WT1 and MUC1 for advanced biliary tract cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2840. doi:10.1158/1538-7445.AM2013-2840