Evaluation of high-risk human papillomavirus testing and anal cytology to detect high-grade anal intraepithelial neoplasia

Abstract

Introduction: Optimal screening for detection of anal precancer has not been established, and most studies involve very high-risk populations. We evaluated high-risk human papillomavirus (HPV) testing and anal cytology to detect high-grade anal intraepithelial neoplasia (≥AIN2) in a cohort with mostly moderate risk factors for AIN.

Methods: Patients ≥35 years old undergoing anal biopsy for various lesions received HPV testing by Roche cobas and a subset by Hologic APTIMA HPV assays with concurrent anal ThinPrep cytology. Biopsies were blindly reviewed by 3 authors, and consensus diagnosis was compared with HPV and cytology results. Sensitivity and specificity for ≥AIN2 detection by HPV testing and cytology (≥ASC-US) were calculated.

Results: Among 64 patients, 19 (29.7%) showed ≥AIN2 on biopsy. All patients were tested by cobas, and 35 (54.7%) were positive. A subset of 39 patients were also tested by APTIMA, and 18 (46.2%) were positive. Positive cytology (≥ASC-US) was present in 37 (57.8%) patients, with 27 (73.0%) of these positive by cobas. HPV testing alone yielded 75.0% and 84.2% sensitivity for APTIMA and cobas, respectively; specificity was 66.7% and 57.8%. Sensitivity and specificity of cytology alone was 78.9% and 51.1%. Combined HPV testing and cytology had a sensitivity and specificity of 91.7% and 37.0% for APTIMA and 94.7% and 40.0% for cobas.

Conclusions: Combined HPV testing and cytology had the highest sensitivity for ≥AIN2 detection, with a performance comparable to cervical cancer screening tests, suggesting this strategy may represent a viable screening option in a population with moderate risk factors for AIN.

Keywords: Anal cytology; HPV; Human papillomavirus; Screening.