ADC similarity predicts microvascular invasion of bifocal hepatocellular carcinoma.

PURPOSE: This study aimed to investigate whether ADC similarity can predict microvascular invasion (MVI) in patients with bifocal hepatocellular carcinoma (HCC).

MATERIALS AND METHODS: Between January 2015 and September 2015, 51 patients with two HCC lesions were included. All patients underwent conventional magnetic resonance imaging including diffusion-weighted imaging (DWI) before the HCC lesions were surgically resected; the tumor specimens were examined histopathologically. Similarity between two HCC lesions regarding DWI signal intensity (SI) and ADC value was calculated as the difference between the two lesions: Value Similarity = [1-(|valuelarge lesion -valuesmall lesion |)/(valuelarge lesion  + valuesmall lesion )] × 100%. Univariate and multivariate logistic regression analyses were performed to assess the presence of MVI.

RESULTS: Risk factors significantly related to MVI of bifocal HCC in univariate analysis were cirrhosis (P = 0.010), histological grade (P = 0.040), DWI SI similarity (P = 0.027) and ADC similarity (P = 0.003). In multivariate analysis, cirrhosis (odds ratio 0.068, P = 0.022) and ADC similarity (odds ratio 1.204, P = 0.008) were independent risk factors for MVI of bifocal HCC.

CONCLUSION: In patients with two HCC lesions, highly similar ADC values for the two HCC lesions may be a preoperative predictor of MVI.