Incidence and characteristics of benign liver space-occupying mass in 17 721 patients with chronic hepatitis B: a color Doppler ultrasound-based case-control study

Abstract

To analyze the incidence and risk factors of benign liver space-occupying mass in patients with chronic hepatitis B (CHB) and the ultrasound features that differentiate these masses from small hepatocellular carcinoma. We retrospectively analyzed the color Doppler and clinical data of 17 721 patients with CHB treated in the Hepatology Unit of Nanfang Hospital between January, 2016 and December, 2017. The data were compared with those of 21629 healthy control subjects undergoing routine physical examination in the Center of Heath Management of Nanfang Hospital during the same period. Compared with the control subjects, the patients with CHB had significantly higher incidences of hepatic cysts (11.8% vs 8.7%, P < 0.05), hepatic hemangioma (8.2% vs 1.6%, P < 0.05) and hepatic cirrhosis nodules (20.6% vs 2.4%, P < 0.05). The incidences of hepatic cysts and cirrhosis nodules increased with age and was significantly higher in male than in female patients (P < 0.001). The highest incidence of hepatic hemangioma was found in CHB patients aged 30-49 years without a gender difference (P>0.05). Sonographically, the benign liver masses commonly showed homogeneous echo within the lesion with clear boundaries and regular shape. Hepatic hemangioma was distinctively hyperechoic in 83.32% (1579/1895) of the patients, while small hepatocellular carcinoma presented with weaker peripheral and internal blood flow signals with a lower flow velocity in the arteries and a higher flow velocity in the portal vein. Liver cirrhosis nodules mostly showed a mixture of strong and weak echoes (79.60%; 7637/9595) without blood flow signal within or around the nodule; an increased volume of the nodule accompanied by heterogeneous echoes within the nodule indicated an increased probability of malignant lesion. Hepatic cysts often displayed no echo within the lesion, but the echo could be enhanced posteriorly. The patients with CHB are at a significantly higher risk of developing hepatic cysts, hepatic hemangiomas and hepatic cirrhosis nodules than the control population, and an older age and the male gender are associated with a higher incidence of hepatic cysts or cirrhosis. The differences in the sonographic and hemodynamic features can help to differentiate hepatic benign mass from malignant lesions, and kinetic changes in sonography can be used to monitor potential malignant transformation of the cirrhotic lesions.