Cellular DNA content and histopathological analysis in hepatocellular carcinoma with multiple nodules

Multiple tumors within the liver are a characteristic feature of hepatocellular carcinoma (HCC). This study investigated alterations in the histologic type and DNA content of multiple nodules of HCC. Both a pathologic examination and flow cytometric DNA analysis were performed on 49 resected specimens of multinodular HCC. The results showed that 35 cases had multiple metastatic satellite nodules around the main tumor (group 1), while 14 had two solitary nodules in different segments without satellite nodules (group 2). In group 1, 28 out of 35 (80.0%) showed a single DNA index while 7 (20.0%) revealed two different DNA contents in the main tumor. The histological type, cytological grade, and DNA index were equivalent between the main and satellite tumors in 100%, 88.6%, and 97.1% of the cases, respectively. In group 2, all tumors showed a single histological type, cytological grade, and DNA index in each nodule. The histological type was identical in 85.7% of the pairs of nodules, but the cytological grade and DNA index were different in 42.9% and 85.7%, respectively. The patients in group 2 showed a significantly higher 5-year survival rate than that in group I (64.8% vs 27.2%, P < 0.05). This study thus indicates that the cytological grade and DNA content are useful in distinguishing multicentric occurrence from intrahepatic metastasis in HCC.