Appraisal of transarterial immunoembolization for hepatocellular carcinoma- A clinicopathologic study

Recurrence of hepatocellular carcinoma (HCC) is frequent, even after appare ntly curative resection. Preoperative transcatheter arterial chemoembolizat ion (TAE) does not improve disease-free survival after hepatic resection. W e previously reported the potential usefulness of transarterial immunoembol ization (TIE), a newly developed arterial embolization technique using OK-4 32 and fibrinogen, as preoperative treatment. In this study, we further inv estigated the effect of TIE by histologic examination of the resected speci mens and compared it with conventional TAE in a prospective nonrandomized m anner. Thirty-nine patients underwent TIE (n = 17) or TAE (n = 22) before c urative hepatectomy for HCC. Transarterial immunoembolization was performed according to the standard protocol using OK-432, fibrinogen, and thrombin. Histologic changes in cancerous and noncancerous liver tissues were examin ed at different stages after TIE. Histologic grading of cancer cell injury according to the modified Shimosato criteria (Grades 0-IV, in increasing or der of severity of cell injury) and postoperative disease-free survival wer e compared between the two groups. Based on the results of histopathology, TAE was more effective than TIE against the main tumor. In contrast, TIE wa s significantly more effective than TAE against extracapsular invasion and intrahepatic metastasis. Disease-free survival after hepatectomy tended to be better in patients pretreated with TIE than TAE. Postoperative tumor rec urrences in the TIE group (n = 4) occurred in the nontreatment regions, whe reas tumor recurrences in TAE group developed mostly (8 of 11 patients) in treated liver regions. Based on results of histologic examination, TIE seem s to be more effective than conventional TAE against extracapsular invasion and intrahepatic metastasis. Data for disease-free survival and recurrence site suggest TIE may be a useful preoperative treatment.