Transarterial chemoembolization for hepatocellular carcinoma: Significance of extrahepatic collateral supply

Purpose: Transarterial chemoemblization (TACE) is the most common treatment modality for treating patients of large unresectable hepatocellular carcinoma (HCC). Extrahepatic collateral arterial supply (ECS) to these large tumors is not uncommon. This study was designed to assess the significance and outcome of TACE in patients of HCC with ECS.
Materials and Methods: A total of 85 patients of HCC of Barcelona clinic liver cancer (BCLC) stage B/C who fulfilled the following inclusion criteria--Child's A/B cirrhosis, normal main portal vein and tumor bulk involvement less than 50% of the liver-were included. TACE was done using cisplatin 100 mg, doxorubicin 50 mg and 20 ml lipiodol followed by gelfoam embolization. Presence of extrahepatic supply to the tumor was looked for in suspected cases. When the collateral supply to the mass was documented, additional chemoembolization through the extrahepatic feeding collateral was attempted. If this was unsuccessful, then the treatment was completed by percutaneous acetic acid ablation (PAI).
Results: Eight patients showed the presence of additional extrahepatic supply to the liver tumor. The sources included inferior phrenic artery, intercostals, internal mammary artery, omental arteries, gastroduodenal artery and branch of the superior mesenteric artery. Successful chemoembolization through these collaterals was achieved in five cases and complete response was noted on follow-up. In the remaining three cases, chemoembolization could not be done and PAI was performed subsequently.
Conclusions: Hepatocellular carcinoma having extrahepatic collateral supply requires additional chemoembolization through the collateral to enhance the efficacy of TACE failing which an alternative locoregional therapy of percutaneous ablation may be resorted to.

Keywords
Extrahepatic supply, hepatocellular carcinoma, multiphasic computed tomography, percutaneous acetic acid ablation, transarterial chemoembolization