HISTOLOGICAL FEATURES PREDICTING MALIGNANT TRANSFORMATION OF NONMALIGNANT HEPATOCELLULAR NODULES - A PROSPECTIVE-STUDY

Background & Aims: Recent advances in imaging modalities allow the ide ntification of borderline hepatocellular nodules that have the potenti al for malignant transformation. The aim of this study was to elucidat e histological predictive features of borderline nodules by needle bio psy for the evolution to hepatocellular carcinoma (HCC). Methods: Thir ty-four hepatocellular nodules diagnosed by needle biopsy were followe d up for more than 6 months. Several histological parameters of these nodules that were related to malignant transformation were evaluated. Results: During the follow-up periods (median, 35 months), 5 of 34 nod ules evolved to HCC during a follow-up of 6-15 months. Significant pro gnostic features of malignant transformation were an increased ratio o f nuclear density of > 1.5, clear cell change, small cell dysplasia, a nd fatty change of the hepatocytes. In multivariate analysis, an incre ased ratio of nuclear density of > 1.5 and clear cell change were inde pendent. Conclusions: A nodule with an increased ratio of nuclear dens ity, clear cell change, small cell dysplasia, and fatty change should be recognized to be a high risk for evolution to HCC. Particularly, th e former two were independent prognostic factors for malignant transfo rmation.