Analysis of DNA ploidy patterns of gastric carcinomas of Japanese.

Ploidy patterns of gastric carcinomas of 54 Japanese patients, ranging in age from 28 to 82 years, were determined by cytofluorometry. The gastric cancers were divided into four basic ploidy patterns; the first pattern was a diploid mode, the second was a heteroploid mode, the third was a mosaic pattern of a diploid and a heteroploid mode, and the fourth was a mosaic of two or more different heteroploid modes. The incidence was 68.4%, 14.8%, 12.9%, and 3.7% in the first, second, third, and fourth patterns, respectively. All the cancers contained polyploid populations, whereas the early cancers tended to contain a lesser amount of polyploid cells than the advanced ones. Diffuse-type cancers and well-differentiated, intestinal-type adenocarcinomas were mostly unimodal cancers of the diploidy or heteroploidy, whereas poorly differentiated adenocarcinomas were often mosaic cancers of several different ploidies. There was no correlation between ploidy patterns and ages and sexes of patients. For 11 cases, labeling indices with 3H-thymidine were determined. Labeling indices of the intestinal-type and diffuse-type cancers were 12% to 27% and 7% to 19%, respectively.