Background: Hepatocellular carcinoma is one of the most common malignant tumors worldwide. Imaging techniques, specially computed tomography and ultrasound, are among the most useful diagnostic tools, although the accuracy of these methods may have a significant variability.
Aims: To determine the prevalence of hepatocellular carcinoma in cirrhotic patients undergoing orthotopic liver transplantation at "Santa Casa de Misericórdia" of Porto Alegre, RS, Brazil; to estimate the sensitivity of computed tomography and ultrasound in pretransplantation detection of hepatocellular carcinoma in this population; to correlate the radiological characteristics with anatomopathological findings.
Materials and methods: Retrospective prevalence study.
Population: adult, cirrhotic patients undergoing orthotopic liver transplantation from January 1990 to July 2003. Among the 292 transplanted patients, 31 cases of hepatocellular carcinoma were diagnosed, of which 29 were included in the study. Tumor characteristics in both ultrasound and computed tomography were compared to those observed in anatomopathological examination.
Results: Prevalence of hepatitis C virus infection among patients with diagnosis of hepatocellular carcinoma was 93.5%, and the prevalence of hepatocellular carcinoma among transplanted patients was 10.6%. The overall sensitivity of the imaging techniques was 70.3% for computed tomography and 72% for ultrasound.
Conclusion: The prevalence of hepatocellular carcinoma at our institution, as well as the sensitivity of both ultrasound and computed tomography to detect such tumors at pretransplantation screening were similar to those found by other authors, while the prevalence of hepatitis C virus infection, the most common etiological agent for liver disease in our patients, is one of the highest ever reported in literature. Factors influencing hepatocellular carcinoma detection rates were: time from examination to liver transplantation; acquisition of computed tomography images during arterial phase; lesion size. Arterial phase proved to be the most useful part of computed tomography examination in this study.