Low-Grade Squamous Intraepithelial Lesion, Cannot Exclude High-Grade Squamous Intraepithelial Lesion: A Category With an Increased Outcome of High-Grade Lesions: Use as a Quality Assurance Measure

"Low-grade squamous intraepithelial lesion (LSIL), cannot exclude high-grade squamous intraepithelial lesion" (LSIL-H) is an increasingly used, equivocal interpretive category in gynecologic cytology. In an effort to evaluate its potential usefulness as a measure of quality assurance, we studied patterns of use of the LSIL-H diagnosis compared with "LSIL" and "high-grade squamous intraepithelial lesion" (HSIL) with corresponding histologic outcomes for 10 cytopathologists in our practice. In our laboratory, while the overall rate of associated cervical intraepithelial neoplasia 2 or greater on histologic follow-up for LSIL-H was intermediate between that of LSIL and HSIL, the outcomes for individual cytopathologists varied widely. Monitoring this particular utilization-outcome data with periodic confidential feedback to individual cytopathologists offers an opportunity for practice improvement within a laboratory and serves as an additional measure of quality assurance. These data may be useful for establishing and/or realigning the diagnostic criteria for this equivocal cytologic interpretation endorsed by a pathology practice.