Can Positron Emission Tomography with the Dual Tracers [11C] Acetate and [18F] Fludeoxyglucose Predict Microvascular Invasion in Hepatocellular Carcinoma?

Microvascular invasion is a poor prognostic indicator of the recurrence of hepatocellular carcinoma (HCC) after surgical treatment. Positron emission tomography (PET) with [F-18]fludeoxyglucose ([F-18]FDG) as a tracer has been employed to predict the prognosis before surgery for various kinds of tumors, but it has not been found to be sensitive enough for HCC. Thus, [C-11]acetate has been adopted as an additional tracer. This study was designed to evaluate the ability of dual-tracer PET ([F-18]FDG and [C-11]acetate) to predict microvascular invasion before liver resection or transplantation. Fifty-eight HCC patients who were preoperatively examined with whole-body dual-tracer PET were studied. Twenty-five patients were [F-18]FDG-positive, and 56 were [C-11]acetate-positive. The sensitivity of [F-18]FDG in detecting primary HCC was 43%, and the sensitivity of [C-11]acetate was 93%. Twenty-nine patients had HCC with microvascular invasion according to the final pathological examination. The sensitivity, specificity, positive predictive value, and negative predictive value of [F-18]FDG PET in predicting microvascular invasion were 55.2%, 69%, 64%, and 60.6%, respectively; the corresponding rates for [C-11]acetate PET were 93.1%, 0%, 48.2%, and 0%. The factors associated with HCC recurrence, which included multifocal involvement, a large tumor size, microsatellite lesions, poor HCC differentiation, and an advanced stage of disease, were analyzed and compared with positive PET results. A tumor size greater than 5 cm was significantly associated with positive [F-18]FDG PET results; [C-11]acetate was not associated with poor prognostic indicators. Preoperative [F-18]FDG PET may predict microvascular invasion. The addition of [C-11] acetate improves the overall sensitivity of PET, but it has no incremental value in predicting microvascular invasion. Liver Transpl 17: 1218-1225, 2011. (C) 2011 AASLD.