Prognostic value of imaging-based parameters in patients with intermediate-stage hepatocellular carcinoma undergoing transarterial radioembolization

Objective Patients with inoperable multilobar hepatocellular carcinoma (HCC) Barcelona Clinic Liver Cancer (BCLC) stage B, who have failed other liver-directed treatment options, are ideal candidates for transarterial radioembolization (TARE) with Yttrium-90 (Y-90)-labeled glass spheres. There is limited data regarding variables that impact the prognosis and outcome in these patients. 99mTc-MAA scan for lung shunt fraction (LSF) and F-18-FDG PET/CT are performed during initial workup. We, therefore, decided to assess the prognostic impact of LSF and metabolic parameters, such as maximum SUVmax, MTV and TLG in patients undergoing TARE for HCC. Methods We retrospectively analyzed 64 patients of HCC, between January 2010 and December 2016, deemed suitable for TARE. Pre-TARE LSF was computed on 99mTc MAA scan, and SUVmax, MTV and TLG on fluoro-deoxyglucose positron emission tomography/computed tomography were measured using automated software by 3D region of interest. LSF and PET parameters were stratified using optimal cut-offs derived from receiver operating curve analysis. Survival curves for the groups were estimated using the Kaplan-Meier method and were compared using log-rank test. Results Overall survival (OS) was 15 months. In univariate analysis, high LSF (greater than 7.19), MTV and TLG were statistically significant and were associated with poor OS. In multivariate analysis, TLG (P value 0.044), MTV (P value 0.290) and LSF (P value 0.010) were independent predictors of outcome, after adjustment for significant univariate variables. However, SUVmax was not statistically significant for OS. Conclusions LSF, MTV and TLG are significant independent prognostic indicators of outcome in patients undergoing TARE for HCC.