Extrahepatic collateral supply of hepatocellular carcinoma by the intercostal arteries

PURPOSE: To evaluate computed tomographic (CT) and angiographic findings of extrahepatic collateral supply of hepatocellular carcinoma (HCC) by the intercostal artery (ICA) and the efficacy of transcatheter arterial chemoembolization (TACE) in the ICA. MATERIALS AND METHODS: The CT and angiographic findings of 30 ICA collateral supplies of HCC in 19 patients were evaluated. TACE of the ICA collaterals was performed in 10 patients. The clinical outcomes and complications were evaluated. RESULTS: ICA collaterals were found at the first to 18th sessions of TACE of HCC. The CT findings were: large HCC (mean diameter, 10.3 cm), subcapsular location (94.7%), defect in iodized oil retention or progression of HCC at subcapsular region (31.6%), HCC abutting the abdominal wall in a broad area with or without abdominal wall invasion (63.2%), hypertrophied ICA (31.6%), and branching collateral vessels coursing from the abdominal wall to the HCC (26.3%). On angiograms, all ICA collaterals originated from the right side at levels of T8 (6.7%), T9 (30.0%), T10 (46.7%), or T11 (16.7%). Twelve sessions of TACE of the ICA collaterals were performed in 10 patients. Follow-up angiography was performed in six patients and showed persistent obliteration in one, recanalization in three, and progression in two. Complications were shoulder pain (n = 2), itching sensation (n = 1), erythema of skin (n = 1), and skin necrosis (n = 1). CONCLUSION: ICA collateral supply of HCC usually occurs in advanced HCC or after multiple sessions of TACE. When there are suggestive CT findings, ICA collaterals should be sought when TACE is performed in the management of HCC.