Practices of Participants in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology, 2006

Abstract

Abstract Context.—Liquid-based preparations (LBPs) and human papillomavirus testing have led to changes in cervical cytology practices. The College of American Pathologists attempts to track practice patterns using a supplemental questionnaire, which allows laboratories to report diagnostic practices. Objective.—To analyze the 2006 reporting practices and to compare the results with the 2003 survey data. Design.—Questionnaire was mailed to 1621 laboratories. Participants included laboratories enrolled in the 2006 College of American Pathologists Gynecologic Proficiency Testing Program or the educational Interlaboratory Comparison Program in Gynecologic Cytology. Results.—Of the 679 responding laboratories (response rate, 42%), most (97.8%; n  =  664) had implemented the Bethesda 2001 terminology. The median rate for all preparations with low-grade squamous intraepithelial lesions was 2.5% (2.9% for LBPs) compared with a 2003 median rate of 2.1%; the increase was confined to LBPs. Rates for high-grade squamous intraepithelial lesions (median, 0.5%) and atypical squamous cells have changed little. High-grade squamous intraepithelial lesions and unsatisfactory rates varied at statistically significant levels between types of LBPs. Most atypical squamous cell cases were subclassified as undetermined significance (median, 4.3%). The median ratio of atypical squamous cells to squamous intraepithelial lesions and carcinomas for all specimen types combined was 1.5, similar to the 2003 median ratio of 1.4. The median rates for findings of squamous cell abnormalities for 2006 were significantly higher for LBPs than for conventional smears. Conclusions.—Most responding laboratories have implemented the Bethesda 2001 terminology. There is an increase in LBP low-grade squamous intraepithelial lesion rates when compared with 2003 data. Liquid-based preparations have higher median squamous intraepithelial lesion and atypical squamous cell rates.