Atrophic Vaginitis Concordance and Interpretation of Slides in the College of American Pathologists Cervicovaginal Interlaboratory Comparison Program in Gynecologic Cytopathology

Context.-Atrophic vaginitis is a commonly reported subset of Papanicolaou test results that are negative for intraepithelial lesion or malignancy, but interpretive criteria overlap with atrophic changes and other entities, hindering concordance among observers. Objectives.-To report on the participant concordance from 2000 to 2009 in the College of American Pathologists Interlaboratory Comparison Program in Gynecologic Cytopathology, with a reference interpretation of atrophic vaginitis, and to investigate cytologic features of good and poorly performing slides to identify criteria useful in the interpretation of atrophic vaginitis. Design.-We summarized 18 302 responses from the program for slides with a reference interpretation of atrophic vaginitis. We randomly selected 18 Papanicolaou test results (3 conventional, 4 SurePath, and 11 ThinPrep) from good and poor performers for prospective, blinded criteria scoring for the following features: abundance of neutrophils, more than 100 degenerating parabasal cells, more than 25% necrotic background, more than 100 pseudoparakeratotic cells, and the presence of stripped or streaked nuclei, histiocytes, and superficial or intermediate squamous cells. Results.-Most Papanicolaou test results (>90%) with a specific reference interpretation of atrophic vaginitis were categorized as negative. Cytotechnologists are more likely than pathologists are to label it negative for intraepithelial lesion or malignancy (NILM) and are equally likely to mistake it for a high-grade lesion. Degenerating parabasal cells, pseudoparakeratosis, and necrotic background are associated with atrophic vaginitis (P = .001) on Papanicolaou. Abundant neutrophils (>100 per x400 field) are also significantly correlated (P = .01). Conclusions.-Exact concordance to atrophic vaginitis is less than 90%. Most of the discrepancies are negative results for intraepithelial lesion or malignancy. Advanced atrophic features are as significant as neutrophils are to the interpretation of atrophic vaginitis. (Arch Pathol Lab Med. 2012;136:1332-1338; doi:10.5858/arpa.2011-0441-CP)