Objective: The aim of this study was to evaluate the prognostic value of metabolic tumor volume (MTV) on pre-treatment F-18 fluorodeoxyglucose (FDG) PET/CT in patients with hepatocellular carcinoma (HCC).
Methods: A total of 59 HCC patients who underwent FDG PET/CT before transarterial chemoembolization (TACE) or transarterial chemotherapy infusion (TACI) were retrospectively enrolled. The region of interest was drawn in the HCC and normal liver tissue. MTV2SD, defined as the sum of the voxels with higher standardized uptake values (SUV) than the SUV of the 97.5th percentile of voxels of the normal liver for each patient, was calculated using an intensity-volume histogram (IVH). The ratio of the maximum SUV of the tumor to the mean SUV of normal liver (T max/L mean) was also calculated. The prognostic significance of MTV2SD and Tmax/Lmean for progression-free survival (PFS) and overall survival (OS) was evaluated along with other clinical factors.
Results: The tumor number, Tmax/Lmean, and MTV2SD were significant prognostic factors affecting PFS (p < 0.05), whereas tumor number, serum alpha-fetoprotein level, tumor stage, portal vein thrombosis, Tmax/Lmean, and MTV2SD were significant prognostic factors for OS (p < 0.05). In multivariate analysis, the tumor number and MTV2SD were independent prognostic factors for PFS (p < 0.05), whereas the independent prognostic factors for OS were tumor number, tumor stage, and MTV2SD (p < 0.05). The mean PFS and OS in patients with low MTV2SD (15.4 and 63.1 months, respectively) were significantly longer than those in patients with high MTV2SD (6.0 and 15.2 months, respectively; p = 0.005 and p < 0.0001, respectively).
Conclusions: Metabolic tumor volume was an independent prognostic factor for PFS and OS in patients with HCC. Therefore, FDG PET/CT can provide valuable prognostic information for HCC patients who undergo TACE or TACI.