Objectives: Nylon-flocked and Dacron swab anal cytology collection procedures were evaluated for detecting high-grade anal intraepithelial neoplasia.
Materials and Methods: Cross-sectional data for 42 HIV-infected and 16 uninfected men who have sex with men have been used. Sequentially collected anal cytology specimens, high-resolution anoscopy, and medical biopsy evaluated the sensitivity and specificity of cytology for predicting high-grade anal intraepithelial neoplasia. Men showing atypical squamous cells (ASC) or more severe findings by cytology were compared with those showing negative for intraepithelial lesions.
Results: The prevalence of high-grade anal intraepithelial neoplasia was 35% (21/58), and findings were approximately 1.5 times higher among HIV-infected compared with uninfected men. Unsatisfactory cytology was twice as common among Dacron compared with nylon-flocked swab protocol specimens (14% [8/58] vs 7% [4/58]). Sensitivity and specificity for the nylon-flocked protocol cytology showing ASC or more severe findings were 81% (58%–95%) and 73% (50%–89%), respectively. Dacron protocol specimens showed 52% (30%–74%) and 58% (34%–80%) sensitivity and specificity, respectively. Men showing ASC or more severe findings using the nylon-flocked protocol cytology showed 3-fold higher odds for high-grade anal intraepithelial neoplasia compared with men with negative results (p < .05), but no statistically significantly higher odds of high-grade anal intraepithelial neoplasia for men showing ASC or more severe findings compared with those with negative results for Dacron protocol cytology (p > .05).
Conclusions: The nylon-flocked protocol better detects high-grade anal intraepithelial neoplasia than does the Dacron protocol, yields more interpretable results, and classifies men with high-grade anal intraepithelial neoplasia as cytologically abnormal 2.5 times more often, even in this small clinical trial.
Clinical trials registration number: NCT00955591.
1Translational Science Section, School of Nursing, University of California at Los Angeles, Los Angeles; 2Los Angeles Gay and Lesbian Center, Jeffrey Goodman Clinic, Hollywood; 3Center for Clinical AIDS Research and Education (University of California at Los Angeles-CARE Center); 4Department of Medicine, David Geffen School of Medicine, University of California at Los Angeles; and 5Jonsson Comprehensive Cancer Center, Los Angeles, CA; 6Tricore Diagnostic Laboratories, University of New Mexico, Albuquerque, NM; and 7University of California at Los Angeles AIDS Institute; and 8Department of Obstetrics and Gynecology, David Geffen School of Medicine, and 9Jonathan & Karin Fielding School of Public Health, University of California at Los Angeles, Los Angeles, CA
Grant support for this project was provided by the UCLA Center for AIDS Research, 5P30AI028697-23, and the National Institutes of Health, National Cancer Institute, Cancer Center Support Grant, UCLA Jonsson Comprehensive Cancer Center, 5P30CA16042-38. Support for this study and demographic data in this article were collected by the Multicenter AIDS CohortStudy with centers (principal investigators) located at The Johns Hopkins Bloomberg School of Public Health (Joseph Margolick); Howard Brown Health Center and Northwestern University Medical School (John Phair, Steven Wolinsky); University of California, Los Angeles (Roger Detels, Otoniel Martinez-Maza); University of Pittsburgh (Charles Rinaldo); and Data Analysis Center (Lisa Jacobson). The Multicenter AIDS Cohort Study is funded by the National Institute of Allergy and Infectious Diseases, with additional supplemental funding from the National Cancer Institute; and the National Heart, Lung, and Blood Institute: UO1-AI-35042, UO1-AI-35043, UO1-AI-35039, UO1-AI-35040, and UO1-AI-35041. Nylon-flocked swab materials for this project were received from Copan Diagnostics Inc.(Murrieta, CA), a branch of Copan Italia S.p.a. (Via Perotti, 10; 25125 Brescia Italy).
Dr. Wiley has received grants and payment for lectures including serviceon speaker’s bureau from Merck & Co., Inc. Dr. Young is as an advisory board member for Roche Molecular Systems and Quidel Corporation. None were declared for the remaining authors.
Reprint requests to: Dorothy J. Wiley, PhD, School of Nursing, University of California atLosAngeles, 700 Tiverton Ave, Factor Bldg, Rm 4-242, Los Angeles, CA 90095-6919. E-mail: firstname.lastname@example.org
Portions of the analysis were presented at the following: (1) 13th International Conference on Malignancies in AIDS and Other Acquired Immunodeficiencies (ICMAOI), Bethesda, MD, November 7 to 8, 2011, P49: “Nylon-flocked swab collection method better predicts high-grade AIN than does Dacron swab method”; (2) 2012 Western Institute of Nursing (WIN) Annual Communicating Nursing Research Conference, Portland, OR, April 18 to 21, 2012, “Directed anal Pap using flocked swab better predicts high-grade AIN than Dacron swab.”