DNA cytometry in abnormal pap-smears of the cervix

DNA cytometry makes it possible to determine the DNA content of a large number of cells and measure the size and form of the nucleus as well as to carry out nuclear structure analyses in cytologically irregular, dysplastic and tumorus cervical smears. 455 smears from 342 patients of a dysplasia consulting service were cytometrically analysed by DNA image analysis. Pap III D lesions revealed highly pathological histograms in 57% (greater than or equal to 5 cells greater than or equal to 5c), Pap IV and V findings in 96% (p < 0.001). The number of aneuploid cells greater than or equal to 5c or greater than or equal to 9c rose significantly with the increasing degree of dysplasia and from CIN I to CIN II or CIN III. Cytological progression is more often found in Pap III D of the high-risk DNA type than in low-risk dysplasias (1-4 cells 5c). In the detection of aneuploid cells greater than or equal to 9c, the additive risk increases 2.57-fold and 6-fold for several cells greater than or equal to 9c. 93% of the lesions that are not classified as CIN histologically (n = 16) but have an irregular history (cytology, HPV infection) exhibit a pathological amount of DNA. HPV types (6/11 vs. 16/18) differ significantly (p < 0.05 in each case) with respect to their DNA classification and degree of aneuploidy (cells greater than or equal to 5c or greater than or equal to 9c). Smoking is shown to have a significant influence on the development of aneuploid cells, Caryometric data like nuclear surface and entropy (chromatin distribution) change with increasing degree of severity of cytological lesions (p < 0.05 or < 0.001). DNA cytometry is a sensitive method which allows rapid analysis of a large number of abnormal cells in a cytological cervical smear. Cytologically detectable alterations and minimal lesions that are difficult to detect by light microscopy can be objectified. The prospective behaviour of dysplasias can be predicted to a certain extent by DNA cytometry. The method is thus suitable for inclusion into the therapeutic management of cytologically and colposcopically irregular patients.