Comparison of α-Fetoprotein Criteria and Modified Response Evaluation Criteria in Solid Tumors for the Prediction of Overall Survival of Patients with Hepatocellular Carcinoma after Transarterial Chemoembolization

PURPOSE To evaluate the value of α-fetoprotein (AFP) classification criteria in predicting tumor response and patient survival and to discuss the agreement between AFP criteria and modified Response Evaluation Criteria In Solid Tumors (mRECIST). MATERIALS AND METHODS Between January 2011 and December 2014, 147 patients with unresectable hepatocellular carcinoma (HCC) with baseline AFP levels ≥ 400 ng/mL who underwent transarterial chemoembolization as initial treatment were retrospectively enrolled for AFP/imaging correlation analysis. AFP-based response was classified as complete response (CR) in cases of AFP level normalization, partial response (PR) in cases of > 50% decrease vs baseline, stable disease (SD) in cases of -50% to +30% change vs baseline, or progressive disease (PD) in cases of > 30% increase vs baseline. Intermethod agreement between the 2 methods was assessed by Cohen κ coefficient. Response rates according to AFP and mRECIST were compared, and the association between response rate and overall survival (OS) was evaluated. RESULTS The κ value for agreement between AFP criteria and mRECIST was 0.549 (ie, moderate), with objective response and disease control rates of 36.1% and 63.3% per AFP criteria and 34.7% and 46.3% per RECIST (P = .807 and P = .003), respectively. Although AFP criteria and mRECIST showed significantly prognostic strata for CR, PR, SD, and PD after chemoembolization (P < .001 for both), some overlap in radiologic PD survival curves was observed. The OS of AFP-based disease control (ie, CR/PR/SD) was significantly longer than that of AFP-based PD among patients with radiologic PD (9.0 vs 6.0 mo; P < .001). CONCLUSIONS The defined AFP response moderately correlated with mRECIST response and yielded accurate prognostic prediction in patients with HCC and AFP levels ≥ 400 ng/mL treated with chemoembolization.