Self-collected versus clinician-collected anal cytology specimens to diagnose anal intraepithelial neoplasia in HIV-positive men

Background: Anal intraepithelial neoplasia (AIN) is common in men who have sex with men (MSM) and may be diagnosed by anal cytology screening. Methods: One hundred two MSM with clinician-collected anal cytology and histopathology specimens were assessed from a cohort study of AIN at the University of California at San Francisco. The men were given a cytology self-collection kit with written instructions for use and requested to collect the sample I month after the clinic visit. Results: Ninety-one percent of self-collected and 99% of clinician-collected anal cytology samples were adequate for interpretation. The sensitivity of abnormal anal cytology to detect AIN by histology was 68% in self-collected samples and 70% in clinician-collected samples, and the sensitivity to detect AIN 2 or AIN 3 was 71% and 74%, respectively. Cytologic results did not differ by grade between self-collected and clinician-collected samples. Among MSM diagnosed with AIN 2 or 3 by biopsy, 33% of self-collected and 39% of clinician-collected cytology samples were high-grade. The sensitivity of both self-collected and clinician-collected samples to detect AIN 2 or 3 was higher among HIV-positive MSM than among HIV-negative MSM. Conclusions: MSM with biopsy-proven AIN can self-collect anal cytology samples with sensitivity comparable with that of experienced clinicians. This may facilitate screening for AIN.