Benign and malignant hepatocellular tumors: evaluation of tumoral enhancement after mangafodipir trisodium injection on MR imaging

The aim of this work was to study the ability of mangafodipir trisodium (Mn -DPDP)-enhanced MR imaging in differentiating malignant from benign hepatoc ellular tumors. Eleven patients with pathologically proved hepatocellular c arcinomas, six with focal nodular hyperplasias, and one with a single hepat ocellular adenoma were examined by spin-echo and gradient-echo T1-weighted sequences before, 1 h after, and 24 h after intravenous injection of Mn-DPD P (5 mu mol/kg). Quantitative analysis including enhancement and lesion-to- liver contrast-to-noise ratio, and qualitative analysis including the prese nce of a central area and a capsule were done on pre- and post-Mn-DPDP-enha nced images. Enhancement was observed in all the tumors with significant im provement (p < 0.05) in contrast-to-noise ratio 1 h after, and 24 h after i ntravenous injection of Mn-DPDP. There were no significant differences in t he mean enhancement and the mean contrast-to-noise ratio (CNR) between beni gn and malignant tumors. No enhancement was seen within internal areas obse rved in 7 hepatocellular carcinomas, and in 5 focal nodular hyperplasias, a nd within capsules which were observed in 9 hepatocellular carcinomas. In o ur study, Mn-DPDP increased CNR of both benign and malignant tumors but did not enable differentiation between benign and malignant tumors of hepatoce llular nature.