Efficacy and nontarget effects of transarterial chemoembolization in bridging of hepatocellular carcinoma patients to liver transplantation: a histopathologic study.

PURPOSE: To histologically evaluate the efficacy and nontarget effects induced by transarterial chemoembolization as a "bridge" treatment of hepatocellular carcinoma (HCC) before liver transplantation (LT) and its relation to patient survival.

MATERIALS AND METHODS: Between October 2003 and January 2011, 51 patients with HCC underwent LT after chemoembolization with iodized oil, small spherical particles, and carboplatin. The decision for LT was made according to national guidelines. The efficacy and nontarget effects of chemoembolization were determined histologically in explanted livers, and their impact on patients' survival after LT was analyzed.

RESULTS: A total of 126 chemoembolization procedures were performed in 51 patients; the median number of procedures per patient was three (range, one to six). The extent of HCC necrosis was less than or equal to 50% in 32% of treated HCCs, more than 50% and less than or equal to 90% in 17%, and more than 90%-99% in 14%; 38% showed complete necrosis of the lesion. The most common nontarget effects were focal necrosis of the liver parenchyma adjacent to the embolized HCC nodule (28%), intralesional (micro)abscess (26%), intralesional hemorrhage (22%), and peritumoral bile duct necrosis (12%). Based on histopathologic examination, 35% of patients had HCC that did not meet Milan criteria. None of these findings was significantly associated with patient survival after LT.

CONCLUSIONS: Transarterial chemoembolization induces histopathologically confirmed HCC necrosis with a high degree of efficacy, but histologically proven complete HCC necrosis was not predictive of survival in this cohort of patients. Although histopathologic examination revealed (clinically relevant) nontarget effects in a subset of patients, they did not impair survival.