Dysplasia and cytologic findings in 4,589 young women enrolled in diethylstilbestrol-adenosis (DESAD) project.

This report presents the cytologic findings and the rates of dysplasia for 4,589 young women enrolled in the National Cooperative Diethylstilbestrol-Adenosis (DESAD) Project. Mucinous columnar cells and/or metaplastic squamous cells with or without mucinous droplets were encountered in 22% of vaginal scrape smears from all diethylstilbestrol (DES)-exposed participants identified by review of prenatal records and in 43% of women in whom vaginal epithelial changes (VEC) were observed by colposcopy or by iodine staining. The frequency of cellular findings in the vaginal scrape smears was closely related to the timing of the administration of the DES to the mother. With increasing age of the daughters, the overall frequencies of both the mucinous and metaplastic cells decreased; relative to each other, an increasing proportion was metaplastic squamous cells. These data suggest that, as the women grow older, vaginal adenosis regresses by the process of squamous metaplasia. Endometrial type cells were found in 2% of vaginal scrape smears. Their cyclical occurrence during the menstrual cycle and lack of correlation with the presence of VEC indicated an origin from the uterine corpus rather than the tuboendometrial type of adenosis. Squamous cell dysplasia of the vagina and cervix was detected by biopsy or scrape smear specimens in 1.8% of DES-exposed women in the record review group. The rate of unexposed women was twice as high. In general, the rates of dysplasia were higher in the cervix than vagina, and the more severe degrees of dysplasia were encountered only in those women who were referred to the DESAD Project or who themselves requested entry. Four patients who were referred or who themselves requested entry were found to have clear cell adenocarcinoma of the vagina. The vaginal smear provided the first clue to the presence of an abnormality in three of them.