A Clinical Scoring System for Predicting Microvascular Invasion in Patients with Hepatocellular Carcinoma Within the Milan Criteria.

Background: Microvascular invasion (MVI) is recognized as a risk factor for early recurrence of hepatocellular carcinoma (HCC) within the Milan criteria after curative treatment.
Methods: One hundred eleven consecutive patients with HCC within the Milan criteria who underwent hepatic resection were retrospectively reviewed. Independent preoperative predictors of MVI were identified, and a scoring system was developed using significant predictors.
Results: MVI was identified in 51 of 111 patients (46%). Multivariate analysis identified the following independent predictors of MVI: alpha-fetoprotein (AFP) of > 95 ng/mL (odds ratio [OR], 9.87; 95% confidence interval [95% CI], 2.24-56.8; P = 0.002), des-γ-carboxy prothrombin (DCP) of > 55 mAU/mL (OR, 5.50; 95% CI, 2.09-15.4; P < 0.001), tumor size of > 2.8 cm (OR, 6.10; 95% CI, 2.07-20.0; P < 0.001), and non-smooth tumor margin in the hepatobiliary phase of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) (OR, 5.34; 95% CI, 1.84-16.9; P = 0.002). A clinical scoring system was developed using these four variables. Within a total possible score of 0 to 4, the prevalence of MVI with a score of 0, 1, 2, 3, and 4 was 4.5%, 24.0%, 45.5%, 91.7%, and 100%, respectively (P < 0.001). The area under the curve of the scoring system was 0.865 based on the receiver operating characteristic curve analysis of the prediction score.
Conclusions: Our clinical scoring system, consisting of AFP, DCP, tumor size, and tumor margin in Gd-EOB-DTPA-enhanced MRI, can be valuable for predicting MVI in HCC within the Milan criteria before curative treatment.