NODULAR REGENERATIVE HYPERPLASIA IN PARTIAL-HEPATECTOMY SPECIMENS

To investigate possible associations of nodular regenerative hyperplas ia (NRH) with antitumor chemotherapy, we reviewed 72 partial hepatic r esections (55 with metastatic tumor, 12 hepatocellular carcinomas, and five benign neoplasms). Thirty autopsy livers from adults without mal ignancies served as controls. Studies included hematoxylin and eosin, reticulin, and trichrome stains and immunostaining for proliferating c en nuclear antigen (PCNA). Five of 72 livers (7%) had NRH. All five pa tients had received chemotherapy, one by intrahepatic artery infusion. Four had received chemotherapy 2 months or less before undergoing par tial hepatectomy. These five cases represented 15% of the 33 patients who received chemotherapy. No NRH was seen in autopsy control livers. In contrast to NRH, multiple hyperplastic foci were seen in 28 of 72 l ivers (39%). This finding did not correlate with chemotherapy. Two of 30 control livers (7%) showed similar mild regenerative changes. In on ly one case of NRH was PCNA staining increased over controls. A band o f PCNA-positive hepatocytes was seen adjacent to the tumor in 21 cases , suggesting that the presence of tumor may cause a local increase in PCNA expression. Mitoses in hepatocytes and assessment of the thicknes s of liver cell plates were more sensitive indicators of regeneration than PCNA. Vascular changes, such as sinusoidal fibrosis (11 of 72 cas es), thickened hepatic arterioles (13 of 72 cases), and mild thickenin g of central veins (10 of 72 cases), did not correlate with NRH, hyper plastic foci, or chemotherapy. No cases of hepatoportal sclerosis were identified.