[Flow cytometric analysis of DNA ploidy in colorectal adenoma].

Flow cytometric measurement of nuclear DNA content in 159 colorectal adenomas was carried out to investigate the relationship between DNA ploidy and the histological findings. DNA aneuploidy was detected in 18 lesions (12.8%). The incidence of DNA aneuploidy was significantly higher in tubulovillous adenomas than in tubular adenomas (30.4% vs. 8.1%; p < 0.01). DNA aneuploidy was not found in any adenoma with mild dysplasia, but was noted in 19.1% of those with moderate dysplasia and in 33.3% of those with severe dysplasia. The mean size of the lesions was significantly larger in adenomas with aneuploidy than in those without aneuploidy (14.0 mm vs. 7.7 mm; p < 0.01). The DNA index values of 18 adenomas with aneuploidy were divided into two groups: one ranged from 1.07 to 1.23 and the other from 1.66 to 1.85. DNA index values correlated with the size of the lesions (p < 0.05), but not with the histologic type and degree of dysplasia.