Hepatocellular carcinoma mimicking cavernous hemangioma on angiography and contrast enhanced harmonic ultrasonography. A case report

A 73-year-old man with chronic hepatitis due to hepatitis C virus was referred to our hospital for close examination of hepatic nodule. An abdominal ultrasonography revealed a mosaic pattern nodule with 3.7 cm in diameter. Arterial phase of dynamic CT revealed the small caudal part and marginal area of cranial part of the tumor were enhanced. The enhancement of marginal area of cranial part of the tumor continued up to portal phase and equilibrium phase and enhanced area was gradually filling in to the central area. On the other hand, the caudal part of the tumor was less enhanced compared with surrounding normal hepatic area in portal phase and equilibrium phase. An abdominal angiography revealed spotty tumor staining mimicking cotton-wool appearance, which is a typical finding for cavernous hemangioma. Contrast enhanced harmonic ultrasonography also showed hemangioma like finding (peripheral globular enhancing pattern). Because of these discrepancies on imagings, it was difficult to make final diagnosis of this tumor to be hepatocellular carcinoma since cavernous hemangioma cannot be completely ruled out. The pathological study of the specimen taken by US-guided percutaneous needle biopsy finally confirmed this nodule as hepatocellular carcinoma. In conclusion, we must keep in mind that some hepatocellular carcinomas could mimic hemangioma due to peliotic change or large acinar formation, therefore, needle liver biopsy may be essential for correct diagnosis if there is a discrepancy in several imaging findings.