PURPOSEMost patients with intrahepatic cholangiocarcinoma (ICC) are not eligible for surgical resection due to advanced stage. We aimed to evaluate the feasibility, local tumor control, and long-term survival of intraoperative radiofrequency ablation (IORFA) with surgical resection to treat unresectable intrahepatic cholangiocarcinoma (ICC).METHODSFrom 2009 to 2016, 20 consecutive patients (12 primary ICC, 8 recurrent ICC) underwent curative IORFA with hepatic resection for surgically unresectable ICC. Patients were not qualified to undergo surgical resection due to multiple lesions causing postoperative hepatic insufficiency and undesirable tumor locations for surgical resection or percutaneous RFA. Of the 51 treated tumors (mean, 2.6±0.9 tumors/patient), 24 were treated by IORFA and 27 were surgically removed. The technical success and effectiveness, overall survival, progression-free survival (PFS), and complications were assessed retrospectively. The overall survival and PFS rates were estimated by the Kaplan-Meier method.RESULTSThe technical success and effectiveness of IORFA were 100%. The overall survival rates at 6 months, 1, 3, and 5 years were 95%, 79%, 27%, and 14%, respectively. The median overall survival time was 22.0±3.45 months. The PFS rates at 6 months, 1, 3, and 5 years were 70%, 33%, 13%, and 13%, respectively. The median PFS was 9.0±1.68 months. The prognosis was significantly worse for patients with recurrent ICC than for patients with primary ICC. One patient (5%) had major complications due to IORFA such as liver abscess and biliary stricture.CONCLUSIONIORFA with surgical resection can be a feasible option for ICC cases that are not amenable to treatment with surgical resection alone. This strategy provides acceptable local tumor control and overall survival.