DNA-PLOIDY IN HUMAN COLORECTAL ADENOMAS

The DNA content of 101 colorectal adenomas of various histologic types resected from 83 patients was determined by image cytometric measurem ents in order to investigate if a correlation between DNA ploidy and p articular histomorphologic features exists and if DNA measurements can be of additional diagnostic value. Overall, 67 of 101 (66%) adenomas showed an aneuploid DNA distribution pattern, including 8 of 19 (42.1% ) mildly atypical, 32 of 48 (66.7%) moderately atypical and 27 of 34 ( 79.4%) severely atypical adenomas. Correlating DNA content with the hi stologic type, 17 of 42 (40.5%) tubular, 28 of 37 (75.7%) tubulovillou s and all 22 villous adenomas exhibited aneuploid DNA histograms. Aneu ploidy was also observed more frequently in larger adenomas. The resul ts show a goon correlation between tumor size, histomorphologic featur es and DNA content. The most remarkable observation is that as many as 42% of the adenomas histomorphologically considered mildly atypical e xhibited aneuploidy. Since aneuploidy has been demonstrated to indicat e premalignant or malignant cellular alterations, DNA image cytometry is suggested for providing valuable additional information on the diag nosis of colorectal adenomas.