Papanicolaou Tests With Mixed High-Grade and Low‐Grade Squamous Intraepithelial Lesion Features: Distinct Performance in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytopathology

Abstract

Abstract Context.—Previous studies have shown that in gynecologic cytology, cases of low-grade squamous intraepithelial lesion (LSIL) and high-grade squamous intraepithelial lesion (HSIL) perform differently on interpretive review. The performance of cases with mixed LSIL and HSIL features is unknown. Objective.—To compare the performance of gynecologic cytology cases of “pure” LSIL and HSIL with cases showing mixed LSIL and HSIL features. Design.—We compiled performance data from the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytopathology from the years 2003 and 2004, and compared the performance of slides showing relatively pure LSIL and HSIL (≤10% misclassification as HSIL and LSIL, respectively) with slides showing mixed LSIL or HSIL features (cases misclassified as LSIL or HSIL >10% of the time). Results.—Interpretations from a total of 4508 cases (2452 HSIL and 2056 LSIL) were analyzed. Overall, the sensitivity of participants on slides with a reference di...