PET Imaging of Woodchuck Model of Hepatocellular Carcinoma

We investigated the feasibility of PET imaging on the woodchuck model of Hepatocellular Carcinoma (HCC) for radiological interventions used in cancer diagnosis and therapy evaluation. Dynamic PET scanning was conducted using [18F]-fluorodeoxyglucose (FDG) to estimate glucose transport rate parameters for correlation with tumor prognostic parameters from histological evaluation. Both HCC bearing woodchucks and the normal control were imaged and compared. The anesthetized animal was scanned with CT and ultrasound before the injection of FDG. Dynamically acquired PET scans along with a series of arterial blood sampling were used to calculate FDG transport rate constants based on a mathematical model of kinetic FDG metabolism. The animal was sacrificed after PET imaging and the liver was harvested and sliced for autoradiography. These slices were then fixed and later sectioned for staining. Tumors on the woodchuck were visualized on PET scans, which was independently validated by Doppler ultrasound (flow) imaging performed on the same day. Histology evaluation confirmed the location and the shape of the tumor region. The transport rate parameters were calculated and compared between liver regions from both normal control, and tumor models. More data is needed for statistical correlation between FDG rate constants and tumor parameters.