Atypical repair on Pap smears: clinicopathologic correlates in 647 cases

The Bethesda system separates atypical reparative changes (ARC) from "typical" repair and places it into the atypical squamous cells of undetermined significance (ASC-US) category. The cytologic diagnosis of ARC represents both diagnostic and management challenges because its clinical significance is controversial and has not been fully investigated. On the basis of scant literature on follow-up of women with ARC on Papanicolaou (Pap) test, we reviewed data from our patient population, which consists of a mixture of low- and high-risk women. Six hundred forty-seven patients with ARC on their Pap tests were identified in a 7-yr period. Of this, 189 (29%) women were lost to follow-up. Of the 458 women with follow-up, 31% had cervical biopsies and 69% were followed by repeated Pap tests. The age ranged from 16 to 86 (mean 47 yr). The incidence of squamous intraepithelial lesion was 5.2% (5% low-grade and 0.2% high-grade). Most women (62%) with ARC on Pap test had a benign condition on follow-up. For some women, the immediate cause was not known and the Pap abnormality resolved spontaneously. Our study questions the validity of reporting ARC within the ASC-US category.