To determine the value of diffusion-weighted magnetic resonance imaging (DW-MRI) in discriminating between hepatic alveolar echinococcosis (AE) and hepatocellular carcinoma and intrahepatic cholangiocarcinoma.

We included 49 patients (27 men, 22 women; mean age: 52.02±9.76 [SD] years; range: 25–72years) with 57 histopathologically confirmed hepatic AE lesions. Fifty patients (18 men, 32 women; mean age: 58.93±8.42 [SD] years; range: 42–71years) with 61 histopathologically confirmed hepatocellular carcinoma and 50 patients (24 men, 26 women; mean age: 50.11±7.70 [SD] years; range: 38–69years) with 54 histopathologically confirmed intrahepatic cholangiocarcinoma lesions were used as control groups. All patients had MRI examination of the liver that included conventional MRI sequences and DW-MRI using b values of 50, 400 and 800s/mm². Two radiologists evaluated conventional MRI and DW-MRI images and calculated ADC values of hepatic lesions.

The mean ADC value of solid components of hepatic AE lesions was 1.34±0.41×10⁻³ mm²/s (range: 0.9–1.59×10⁻³ mm²/s) and was significantly higher than that of the solid components of hepatocellular carcinoma lesions (mean ADC value, 0.99±0.29×10⁻³ mm²/s; range: 0.7–1.15×10⁻³ mm²/s) and of intrahepatic cholangiocarcinoma lesions (mean ADC value, 1.05±0.22×10⁻³ mm²/s; range: 0.86–1.18×10⁻³ mm²/s) (P<0.001).

In general ADC values can help discriminate between AE and hepatocellular carcinoma and intrahepatic cholangiocarcinoma. However, the use of ADC values cannot help differentiating Type 4 AE from hepatocellular carcinoma or intrahepatic cholangiocarcinoma.