NONDIAGNOSTIC SQUAMOUS ATYPIA OF THE CERVIX (ATYPICAL SQUAMOUS EPITHELIUM OF UNDETERMINED SIGNIFICANCE) - HISTOLOGIC AND MOLECULAR CORRELATES

The histologic criteria for reactive/reparative lesions and precursor lesions (squamous intraepithelial lesions; SIL) of the cervix are esta blished, but a proportion of cervical biopsies contains squamous epith elial alterations that do not fall into either category (nondiagnostic squamous atypia or atypical squamous epithelium of undetermined signi ficance). This study examined (a) the degree to which this diagnosis c ould be made consistently between two experienced pathologists and (b) its relationship to papillomavirus nucleic acids. One author selected 37 cervical biopsies with a spectrum of cellular changes occurring in the context of inflammatory or reactive epithelial changes, and each case was reviewed by two pathologists independently and classified as reactive, nondiagnostic atypia, and diagnostic (SIL). Concordance betw een two observers was highest for a diagnosis of SIL (kappa = 0.68), f ollowed by reparative/reactive (kappa = 0.48). Concordance for a desig nation as nondiagnostic squamous atypia was fair (kappa = 0.39). Seven of 37 (19%) cases were HPV positive, including 2/7, 5/19, and 0/11 ca ses designated by at least one observer as SIL, nondiagnostic squamous atypia, or neither (i.e., both reactive), respectively. The findings support a category of nondiagnostic squamous atypia but emphasize the value of a second observer and possibly, HPV DNA testing, in resolving such cases. Similarities in HPV positivity between nondiagnostic atyp ia and SIL in this study may reflect problems of both criteria selecti on and consistent application of these criteria in a setting of reacti ve/reparative changes.