Alessandro Furlan MD, Presenter: Nothing to Disclose

Omar Almusa MD, Abstract Co-Author: Nothing to Disclose

Igor Dvorchik, Abstract Co-Author: Nothing to Disclose

James Wallis Marsh MD, Abstract Co-Author: Nothing to Disclose

Mitchell E. Tublin MD, Abstract Co-Author: Nothing to Disclose

Kyongtae Tyler Bae MD, PhD, Abstract Co-Author: Patent agreement, Covidien AG, Saint Louis, MO Patent agreement, Bayer AG, Pittsburgh, PA Expert Advisory Committee, Bracco Group, Princeton, NJ

Fractional allelic imbalance (FAI) of tumor suppressor genes ≥27% is an acknowledged genetic marker for HCC aggressiveness. The purpose of this study was to compare the CT and MR phenotypic imaging features of HCC with the FAI index rate.

This retrospective study was IRB-approved. From 110 patients with HCC and tumor genetic analysis performed following liver transplantation or resection, we selected 38 patients (28 M, 10F; mean age 63 years) who met the following inclusion criteria: one HCC, available CT or MRI before genetic analysis, and absence of tumor treatment before imaging. CT (n=29) and MR (n=9) were performed with dedicated triphasic contrast-enhanced liver imaging protocols. Imaging studies were retrospectively reviewed by two radiologists (by consensus) to qualitatively assess the following imaging features: maximum tumor transverse diameter; lesion attenuation/signal heterogeneity; presence of intratumoral fat, necrosis, calcifications, or hemorrhage; enhancement pattern (hypervascularity, washout); perilesional capsule; background liver (cirrhotic morphology, patency of portal veins); stigmata of portal hypertension (splenomegaly, varices, and ascites); abdominal adenopathy and distant metastasis. Tumor aggressiveness was defined as FAI rate index ≥27%; t-test was used to determine significance of difference in size between tumors with FAI<27% vs. FAI≥27%; Chi-square was used for assessing differences in the remaining dichotomous variables. Candidate variables (p<.05) were subsequently subjected to stepwise multiple logistic regression.

FAI index rate ranged 0-86% (mean, 35%); 22 (58%) HCCs had FAI<27%, and 16 (42%) HCCs had FAI≥27%. Imaging findings significantly associated with FAI≥27% were larger tumor diameter (8.7 cm vs. 3.5 cm, p=.001), lesion heterogeneity (19 vs. 4, p<.001), intratumoral necrosis (15 vs. 3, p=.003), and tumor hypervascularity (21 vs. 11, p=.038). Stepwise multiple logistic regression analysis revealed lesion heterogeneity to be the strongest predictor of FAI≥27% (p<.001).

Genotypically aggressive HCCs are significantly associated with an increase in tumor size, necrosis, hypervascularity, and lesion heterogeneity.

Knowledge of the genotype and imaging phenotype associated with the early prediction of HCC progression and recurrence will help the selection of appropriate organ allocation for patients with HCC

Furlan, A, Almusa, O, Dvorchik, I, Marsh, J, Tublin, M, Bae, K, Tumor Aggressiveness of Hepatocellular Carcinoma (HCC): Genotype versus Imaging Phenotype.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9006325.html