Hepatocellular carcinomas within the Milan criteria: Predictors of histologic necrosis after drug-eluting beads transarterial chemoembolization

Purpose: To evaluate pathologic, imaging, and technical predictors of therapy response in patients with hepatocellular carcinoma (HCC) within the Milan criteria undergoing doxorubicin drug-eluting beads transarterial chemoembolization (DEB-TACE) before orthotopic liver transplantation (OLT). Methods: This prospective study included consecutive patients with HCC who underwent DEB-TACE before OLT. Tumor histologic necrosis on liver explants was utilized as the standard of reference to categorize treated HCCs as group 1 (>50 % necrosis) or group 2 (≤50 % necrosis). DEB-TACE technique, histological factors, and imaging evaluation utilizing the modified Response Evaluation Criteria in Solid Tumors (mRECIST) were compared between groups 1 and 2. Results: Twenty-seven HCCs were identified in 23 patients. Group 1 comprised 18 HCCs (mean necrosis 86.2 %). Group 2 comprised 9 HCCs (mean necrosis 31.1 %). The mean time between the last DEB-TACE session and the OLT was 112 days. Lesion size was significantly larger in group 1 (mean 3.2 cm; 95 % confidence interval 2.55-3.85) than in group 2 (mean 2.1 cm; 95 % confidence interval 1.79-2.48) (p = 0.030). Group 1 also demonstrated a higher frequency of encapsulated lesions when compared to group 2 (78 % vs. 22 %; p = 0.0027). A significant linear correlation was found between the quantification of necrosis by imaging and pathology (p = 0.0011) using the mRECIST, with a poorer correlation index in group 2. Conclusion: Larger and encapsulated HCCS are associated with a higher percentage of necrosis. A significant linear correlation between the amount of necrosis by imaging and pathology was encountered when mRECIST was utilized.