Prognostic Value of Metabolic Parameters of 18F-FDG PET/CT and Apparent Diffusion Coefficient of MRI in Hepatocellular Carcinoma.

BACKGROUND: The aim of this study was to predict the survival of patients with hepatocellular carcinoma (HCC) by examining metabolic PET parameters, apparent diffusion coefficients (ADCs), and clinical parameters.

METHODS: We retrospectively reviewed 52 patients with pathologically confirmed HCC (age, 57.9 ± 10.7 years; 43 men) who underwent MRI and F-FDG PET/CT. The tumor-to-normal liver SUV ratio (TLR), the mean ADC of each tumor, and other clinical data were obtained. Survival analysis was performed.

RESULTS: Thirty-two patients died during the follow-up period. There was an inverse correlation between the mean SUV and the mean ADC of a tumor (r = -0.402, P = 0.020). Among HCC patients, disease-specific survival was significantly associated with each of the following factors: high TLR (TLR ≥ 2; hazard ratio [HR], 3.78; P = 0.001), high mean ADC (mean ADC ≥ 1.250 × 10 mm/s; HR, 0.45; P = 0.028), AFP ≥ 400 ng/mL (HR, 3.48; P = 0.001), PIVKA-II ≥ 100mAU/mL (HR, 6.39; P = 0.011), tumor size (HR, 1.13; P < 0.001), number of tumors (HR, 2.16; P = 0.031), tumor stage (HR, 3.08; P < 0.001), and surgery for initial treatment (HR, 0.06; P < 0.001). The results of multivariate analysis show that DSS was significantly associated with each of the following factors: TLR ≥ 2 (HR, 2.46; P = 0.044), PIVKA-II ≥ 100mAU/mL (HR, 5.11; P = 0.037), tumor stage (HR, 3.01; P < 0.001), and surgery for initial treatment (HR, 0.04; P < 0.001).

CONCLUSIONS: High TLRs and low mean ADCs were associated with poor outcomes. The TLR was an independent prognostic factor in patients with HCC, but the mean ADC was not. A negative correlation was found between the mean ADC and the mean SUV of a tumor.