FLOW CYTOMETRIC ANALYSIS OF DNA CONTENT AND CELL-KINETICS IN COLORECTAL-CARCINOMA

DNA ploidy and cell proliferation were studied by means of flow cytome try in 98 patients with primary colorectal adenocarcinoma. Multiple sa mples of tumour burden were pooled and freshly dissociated immediately after surgery for FACS analysis. The relationships between Ploidy, pr oliferative activity, evaluated in terms of S-phase percentages (%S), and some clinico-pathological variables were analyzed. 87 of the 98 tu mors yielded evaluable DNA histograms: 32 were diploid (37%) and 55 we re aneuploid (63%; median DNA index=1.6). Multiple aneuploid cell popu lations were found in 15 tumors (17%). The % S was estimated by means of a mathematical model. Aneuploid tumors showed % S values significan tly higher than diploid ones (p < 0.0001). Differences in the distribu tion of DNA aneuploidy were observed in relation to Dukes' stage and t umor site, left colon, rectum and stage D tumors being more frequently aneuploid. No significant differences in proliferative activity were observed in relation to most of the clinical variables, except for hig her % S values observed in tumors of right colon compared to those of left colon and rectum.