The Incidence of Cervical and Vaginal Dysplasia After Exposure to DES-Reply

In Reply.—  Dr Richart asserts that advances in our knowledge about the morphological appearances of HPV could have led to bias in the National Collaborative Diethylstilbestrol Adenosis Project study, in which tissue slides have been analyzed since 1976.¹ Although some bias is possible, we believe it to be minimal since the slides disclosing dysplasia were reviewed by all pathologists and cytologists, and many slides were rereviewed periodically over a period of years as part of quality-control procedures.A major problem facing all pathologists and cytologists today is in fact the diagnostic criteria distinguishing HPV lesions from dysplasia and carcinoma in situ (collectively, Richart's CIN). Do lesions exhibiting both koilocytosis and marked nuclear atypia represent one disease state or both simultaneously? We have demonstrated that such lesions may have HPV demonstrable by immunoperoxidase stains while also demonstrating aneuploidy by microspectrophotometric analysis of Feulgen-stained slides.² We believe that many lesions