STUDY OF CELL-KINETICS IN THE NORMAL COLORECTAL MUCOSA OF SUBJECTS ATRISK OF DEVELOPING COLORECTAL-CARCINOMA

This report examines the H-3-thymidine-labeling index (LI), the now cy tometric S-phase cell fraction, and DNA ploidy in the normal colorecta l mucosa of three groups of subjects: normal subjects (group A), patie nts with adenomas (group B) and patients with cancer (group C). The to tal LI and the LI for crypt compartment were investigated. The former LI was similar in the three groups while that for crypt compartment wa s significantly higher in the patients with adenomas (compartment 3), and in those with cancer (compartments 3 and 4). All of the mucosas we re diploid and no significant relationship was found between the LI an d the flow cytometric S-phase values, considered for each group. These data suggest that an upwards expansion of the proliferative compartme nt seems to be an indicator of cancer risk. In contrast, the variation s of the ploidy and S-phase fraction do not appear to be important ris k factors in the three groups of subjects studied.