Complete response to tremelimumab plus durvalumab treatment in hepatocellular carcinoma with a bile duct tumor thrombus: A case report.

Tremelimumab plus durvalumab (Dur/Tre) is the first-line treatment for advanced hepatocellular carcinoma (HCC) worldwide. The present report describes the case of a 68-year-old man diagnosed with advanced HCC and a bile duct tumor thrombus (BDTT) who achieved a complete response to Dur/Tre therapy. The BDTT progressed to the bifurcation of the left and right hepatic ducts. Over time, both the tumors and BDTT progressively decreased in size, and a complete response was confirmed using the Response Evaluation Criteria in Solid Tumors (version 1.1.) 6 months after treatment administration. Subsequently, immune-related adverse events, including type 1 diabetes mellitus and diabetic ketoacidosis, emerged, leading to treatment discontinuation. The patient was undergoing outpatient follow-up in a drug-free state with no signs of recurrence 290 days after the initial administration of Dur/Tre. Although long-term and meticulous observations are required, the present findings could influence the choice of systemic chemotherapy for advanced HCC.