Liver magnetic resonance imaging for evaluation of response to treatment after stereotactic body radiation therapy of hepatocellular carcinoma

Figure 13  Hepatocellular carcinoma in a 75-year-old man treated with stereotactic body radiation therapy. A and B: Diffusion-weighted imaging signal of a lesion located in segment VII, before and after treatment. In the pre-therapy evaluation, the nodule presented a marked narrowing of the diffusion of water molecules, a feature no longer present at post-stereotactic body radiation therapy (SBRT) examination; C: Hepatocellular carcinoma nodule located in segment VII characterized by intermediate signal on T2-weighted imaging; D and E: Initial capsular retraction (white arrow) was already evident at the first post-SBRT magnetic resonance examination and particularly evident at the 9 mo follow-up; F and G: SBRT outcomes characterised by an area of "band" hypodensity in the hepatic excretion phase in the axial and coronal sequences, corresponding to shaded hyperintensity in the T2-weighted sequences with the same distribution and morphology; H: These findings are an expression of treatment-induced fibrosis as demonstrated by the histological finding, where postradiotherapy fibrotic tissue can be identified after liver transplantation.