Cell features and patterns in fine-needle aspirates of hepatocellular carcinoma

The values of the cytologic features of individual cells and cellular patterns in aspirated materials in the diagnosis of 49 hepatocellular carcinomas (HCC) were investigated. Excellent cytologic specimens were obtained by percutaneous aspiration biopsy with a heparinized fine 22-gauge needle. In the well-differentiated type of HCC, a correct diagnosis of malignancy was difficult from the cytologic features of individual cells because of their resemblance to normal hepatocytes. In contrast, in moderately differentiated and poorly differentiated types of HCC, a correct diagnosis of malignancy was easily made from the features of individual cells, but there was little or no cytologic evidence of the hepatic origin of the cells. Comparison of histologic and cytologic findings in aspirated materials obtained from the same patients showed that the cellular patterns seen in cytologic specimens faithfully reflected the histologic structures of HCC. Various characteristic cellular patterns were recognized only in specimens obtained from patients with HCC, but not in those from patients with benign liver diseases. These cellular patterns were very useful not only for diagnosis of malignancy, but also for identification of the hepatic origin of cells. A combination of the features of individual cells and of characteristic cellular patterns raised the diagnostic rates for well-, moderately, and poorly differentiated types of HCC to 90.5%, 100%, and 100%, respectively.