Direct correlation between sonography and histology of minute malignant hepatic nodule

To improve the qualitative diagnosis of ultrasonography (US) of minute malignant hepatic nodules, we studied the accurate and direct correlations between US and histopathology of 33 lesions using formalin-fixed autopsied livers. The target nodules were cut on the same plane as their US-image. The solid nests of malignant tumor without degeneration were hypoechoic on US. Hepatocellular carcinoma showed a wide variety of echo levels, from hypoechoic to isoechoic, and its images were more heterogeneous than those of other malignant lesions. The squamous cell carcinoma ranged from hypoechoic to hyperechoic according to the degree of keratinization. US may be useful for evaluating the degree of differentiation in squamous cell carcinoma. Marked mucin-production and "comedo" pattern seem to be histological factors of the hyperechoic US image of adenocarcinoma. This study may contribute to improve the quality of US-diagnosis of minute hepatic nodular lesions.