Background & aims: The preneoplastic role of macroregenerative nodules in cirrhosis is still debated. Thirty-two consecutive ultrasonography-detected macronodules were followed up to evaluate whether and which lesions are the actual precursors of hepatocellular carcinoma, if histology can identify preneoplastic macronodules, and whether additional parameters are related to neoplastic evolution.
Methods: Macroregenerative nodule classification was based on recently proposed histological criteria. Extranodular liver cell dysplasia was also evaluated. The follow-up included ultrasonography and serum alpha-fetoprotein level determination every 3 months.
Results: Twenty-two macronodules (78%) were classified as typical and 7 (22%) as atypical. Twenty-one were hypoechoic, and 11 were hyperechoic. Extranodular dysplasia was more frequently associated with atypical than typical macronodules (5 of 7 vs. 6 of 22). After 28 +/- 15 months, neoplastic transformation occurred in 8 macronodules (25%) and was more frequent in atypical than in typical (5 of 7 vs. 3 of 25), in hyperechoic than in hypoechoic (5 of 11 vs. 3 of 21), and in extranodular dysplasia-associated macronodules than in extranodular dysplasia-free macronodules (5 of 11 vs. 2 of 18). Five hepatocellular carcinomas appeared outside the original macronodule.
Conclusions: Atypical macroregenerative nodules can be considered precursors of hepatocellular carcinoma. Histology is useful in identifying preneoplastic macronodules, and hyperechoic pattern and extranodular dysplasia are additional risk factors for neoplastic transformation.