Hepatocellular carcinoma: CT and MR features after transcatheter arterial embolization and percutaneous ethanol injection.

PURPOSE: To investigate the reliability of computed tomography (CT) and magnetic resonance (MR) imaging in the evaluation of the response of hepatocellular carcinoma (HCC) to transcatheter arterial embolization (TAE) followed by percutaneous ethanol injection (PEI). MATERIAL AND METHODS: Between January 1991 and November 1992, 20 patients (15 men and five women, aged 53-73 years [mean, 64.6 years]) with 31 HCC lesions underwent CT and MR imaging before and after treatment with combined TAE and PEI. RESULTS: Twenty-seven tumors, which were hypointense on post-treatment T2-weighted images and on gadolinium-enhanced T1-weighted images, were seen to be necrotic at biopsy. In four cases of incomplete necrosis, viable tumor was hyperintense on T2-weighted images and was enhanced after administration of contrast material. CT provided a larger spectrum of imaging features as a result of the presence of both hyperattenuating areas (caused by retention of iodized oil) and hypoattenuating areas (due to ethanol-induced necrosis). CONCLUSION: CT and MR imaging findings proved useful in the evaluation of the response of HCC to combined TAE and PEI.