Flow cytometric DNA analysis of hepatocellular carcinoma

In recent years, considerable interest on the part of researchers has been directed towards using modern techniques to identify new prognostic indicators for cancer, to be used in addition to traditional prognostic factors such as cancer stage and histological (pertaining to cells) grade. One method that is becoming popular is the use of flow cytometry (cell counting and analysis) to measure the DNA content of cancer cells. In many cases, but not all, abnormal DNA content, which is indicative of aneuploidy (an abnormal chromosome complement), is associated with a worse outcome than is a DNA content that is indicative of the normal diploid chromosome complement. The method of flow cytometry has now been applied to hepatocellular carcinoma. Hepatocellular carcinoma, a form of liver cancer, is especially common in Asia and Africa, and is the third most common cause of cancer deaths among Japanese men. The analysis of cell ploidy was performed on 203 patients using flow cytometry; 46 specimens could not be completely processed due to technical difficulties. Half the remaining patients had DNA measurements indicating aneuploidy. These patients has a significantly worse outcome than did the patients with diploid tumors; the aneuploid and diploid patients had five-year survival rates of 12 and 54 percent, respectively. Furthermore, it was observed that among patients with aneuploid cancer, those with a DNA index of less than 1.5 survived for a shorter period than those who had a greater DNA index. The DNA index is simply the ratio of quantity of DNA to that of a normal diploid cell. (The DNA index for a diploid cell is therefore 1.0). For some cancers, aneuploidy might correlate with traditional variables such as histologic grade, and therefore not add anything new to the prognosis. However, a multivariate analysis of the data for hepatocellular carcinoma revealed that DNA content, vascular invasion, and metastatic spread within the liver served as both useful and mutually independent predictors of outcome. (Consumer Summary produced by Reliance Medical Information, Inc.)