Prognostic value of combined [99m]Tc-MAA-SPECT/CT and [18F]Fluoroethylcholine-PET/CT in patients suffering from advanced hepatocellular carcinoma prior to radioembolization

Objectives Hepatocellular carcinomas (HCC) are increasingly treated with radioembolization (RE). However, prognostic factors with regard to survival are needed for better patient selection.

Methods 24 patients with advanced HCC underwent MAA-SPECT/CT und FEC-PET/CT prior to RE. We evaluated various uptake parameters, tumor-to-spleen-ratio and volumetric overlap of uptake on MAA-SPECT/CT and FEC-PET/CT using Hermes Hybrid 3D viewer. This data was analyzed with regard to survival. We used ROC analysis, Youden-index, multiple logistic regression analysis and Kaplan-Meier analysis for statistical analysis.

Results All patients died with a median survival of 437±71 days. A high overlap of MAA SPECT/CT and FEC PET/CT was significantly associated with a shorter survival (AUC=0,75; P<0,05). A combination of SUV values, tumor-to-spleen-ratio and volumetric data using multiple logistic regression had an AUC of 0.87 (P=0.004) with a sensitivity of 100%, specificity of 75%, accuracy of 92%, a NPV of 89% and a PPV of 100% (P<0.001). Regression analysis was able to separate patients with regard to prognosis (median survival 531±68 days versus 840±96 days; log rank: 5.7; P=0.017).

Conclusions Patients suffering from advanced HCC and a combination of high overlap of MAA-uptake (as a parameter for high tumor vascularization) and FEC-uptake have a significantly shorter survival as the remaining patients. This finding may aid to enhanced patient selection for RE.