Clinicopathological significance of the peritumoral decreased uptake area of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid in hepatocellular carcinoma

Background and Aim: A faint hypointensity in the noncancerous tissue around hepatocellular carcinoma (HCC) in the hepatobiliary phase of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) is encountered. The goal is to elucidate the significance of this type of pseudolesion designated as the peritumoral decreased uptake area of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) (PDUAE). Methods: This study group consisted of 61 patients with 61 surgically resected HCCs who underwent preoperative Gd-EOB-DTPA-enhanced MRI. The presence of a faint and hypointense area around the tumor in the hepatobiliary phase was defined as PDUAE. The frequency with which PDUAE was seen was compared between pairs of groups determined by clinical and pathological parameters using a Fisher's exact probability test. The parameters showing significant differences in this test were further tested by multiple logistic regression analysis. Results: PDUAE was observed in 25 cases. In univariate analysis, the values of alpha-fetoprotein and protein-induced by vitamin K absence or antagonist-II, maximal diameter, the presence of a capsule, and vascular invasion were significantly correlated with the frequency with which PDUAE was seen. In multivariate analysis, only maximal diameter and vascular invasion were significantly correlated. When the presence of PDUAE was used as an indicator of vascular invasion, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 72%, 80.6%, 77%, 72%, and 80.6%, respectively. Conclusions: By using this indicator, "microscopic" vascular invasion of HCC can be easily predicted with Gd-EOB-DTPA-enhanced MRI.