Is hepatic ultrasonography a valid alternative tool to liver biopsy? Report on 507 cases studied with both techniques

In order to evaluate the diagnostic potential of liver ultrasonography (US), the charts of 23 cases with normal liver, 424 patients with chronic widespread, and 60 patients with focal hepatic diseases, who had undergone both US and liver biopsy, were reviewed. The positive predictive value of US was good in all hepatic disorders (range 86.9-96.5%), while its negative predictive value was very low (range 14.1-42.5%) in the various forms of widespread liver disease and suitable for screening purposes (74%) in focal lesions. Of the 507 cases, 39 with an ultrasonically suspected liver mass also underwent an echo-guided fine-needle aspiration, which showed a high sensitivity (85%) in the 27 biopsy-proved malignant lesions and excluded tumor cells in the remaining 12 cirrhotic cases. As regards US tissue diagnosis, hepatic tumors, fatty infiltration, and fibrosis were detected in 88%, 60%, and 49% of cases, respectively. Fat and fibrous content on biopsy were similarly and significantly correlated with both echo pattern and sound attenuation. Overall results suggest that in the group of widespread hepatic disorders the usefulness of US is greatly reduced by the fact that the patient's actual condition is not likely to be negative if US examination is normal and by the impossibility of differentiating fat from fibrosis. In focal lesions, the diagnostic value of US appears high and the method may frequently provide conclusive proof of the tumor if a positive cytodiagnosis on echo-guided aspirated material is done.