[Cytofluorometric analysis of cell proliferation kinetics of the human colorectal cancer].

In order to clarify cell proliferation kinetics of human colorectal cancer, 91 cases were investigated by cytofluorometry and clinicopathological findings. The results showed colorectal cancers could be divided into 3 groups according to the ploidy pattern. Group I was the diploid cell population, group II the polyploid cell populations and group II' the aneuploid cell populations. These ploidy patterns were found not to be related both to the histological types and the gross pathological classification. Most of the intramucosal cancers were found in group I, and the cancers of more advanced growth mainly in groups II and II'. The fraction of diploid cells in the groups I and II' did not show the remarkable change, but in the group II decreased with tumor progression. These results indicate the ploidy patterns appear to change with the submucosal invasion, and also that while the ploidy patterns in the groups I and II' are stable, those in the group II increase the extent of polyploidization with the tumor growth. Lymphatic metastases were found to be more frequent in the group II than in the groups I and II'. It is suggested that the mechanism of lymphatic metastasis would be related to the cell polyploidization.