Transarterial chemoembolization for omental vein tumor thrombosis in hepatocellular carcinoma: a case report

In hepatocellular carcinoma (HCC) patients, recognizing major vascular invasions such as portal vein tumor thrombosis (PVTT) and hepatic vein tumor thrombosis (HVTT) is crucial for disease staging. Less documented is the invasion of other vessels. We report a case of omental vein tumor thrombosis (OVTT) in an HCC patient treated with transarterial chemoembolization (TACE). A 74-year-old male patient with hepatitis B infection was diagnosed with HCC in segment 8 five years ago and treated with radiofrequency ablation (RFA). The tumor recurred at the ablation site, measuring 25 mm × 18 mm, invading the portal vein branch of the posterior segment and a omental vein, showing tumor thrombosis. The patient received TACE targeting branches from the right hepatic artery and omental artery. After two TACE sessions, the tumor and thrombosis completely responded, and tumor markers returned to normal. This case report highlights the uncommon presentation of OVTT alongside PVTT in advanced HCC, emphasizing the need for vigilance in diagnosing atypical disease progressions in HCC and a possible treatment efficacy of TACE.