Macroregenerative nodules of the liver in primary biliary cirrhosis: report of two autopsy cases.

Recently, macroregenerative nodules of the liver have been regarded as putative precancerous lesions in human cirrhotic livers. We describe the morphologies of two macroregenerative nodules, one benign and another harboring a malignant hepatocellular focus, occurring in two patients with primary biliary cirrhosis, both at the cirrhotic stage. The macroregenerative nodules of both patients were found incidentally at autopsy. The macroregenerative nodule of case 1 (42-yr-old female) was composed of hyperplastic hepatocytes with little atypia. The macroregenerative nodule of case 2 (67-yr-old male) had a malignant focus, in addition to atypical hepatocytes. The atypical hepatocytes showed mild nuclear crowding, slightly increased nucleocytoplasmic ratio, and mild nuclear hyperchromasia. The malignant focus was free of stainable iron against the mildly siderotic background. These findings may support the concept that macroregenerative nodules can also be a preneoplastic lesion in primary biliary cirrhosis.