DNA measurements and micronuclei in human rectal carcinoma

It has been recognized that the variability among individual human tumors is tremendous. We investigated DNA content and cell proliferation in 81 patients with rectal carcinoma by cytophotometric methods. Among them, 32 patients showed only diploid cells and 41 patients hyperploid cells, and the former had better prognoses than the latter. The percentage of S cells calculated from the DNA histograms and the number of cells with micronuclei were higher in proliferative tumors. Clinically, probably due to repopulation in the tumor 10 to 15 days after preoperative radiotherapy, the number of S cells increased and local recurrence was found several months after surgical resection in more than a few cases. These data suggest that the biological variability of human tumors is extraordinary and individualization of tumor therapy is greatly indicated. Furthermore, the above parameters may help to obtain indicators for the prognosis and thereby improve therapy.