Perianal warts as a risk marker for anal high-risk-human papillomavirus (HPV) detection and HPV-associated diseases

Genital warts are the most common sexually transmitted infection (STI) and are caused by human papillomavirus (HPV). Persistent anal infection by oncogenic genotypes of HPV is a determinant for anal cancer. Currently, anal cancer screening is not widely implemented.

Our aim is to evaluate the role of perianal warts as a risk marker for anal high-risk (HR) HPV detection and anal dysplasia.

In this observational, retrospective, cohort study of attendees of a STI outpatient clinic between January 2010 and June 2018, all human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) who performed anal cytology, anal HPV DNA detection and anoscopy were included. A comparison was made between patients with and without perianal warts. Primary endpoint: proportion of patients with an abnormal anal cytology. Secondary endpoints: proportion of patients with (i) anal HR-HPV detection; (ii) anal HPV 16 detection; (iii) abnormal anal biopsy; and (iv) anal high-grade squamous intraepithelial lesion (HSIL).

Seventy-eight individuals were included: 39 with perianal warts and 39 without perianal warts. Subjects with perianal warts more frequently had an abnormal anal cytology (71.8% vs. 38.5%; P = 0.003). This group also had a higher rate of anal HPV 16 detection (38.5% vs. 12.8%; P = 0.01). No differences were detected in the proportion of patients with anal HR-HPV detection, with an abnormal anal biopsy or with anal HSIL. Perianal warts was an independent risk factor for an abnormal anal cytology (OR: 7.2) and for anal HPV 16 detection (OR: 6.7).

Given the high risk of anal cancer in HIV-positive MSM, effective screening strategies are greatly needed. This study suggests that the presence of perianal warts is a suitable risk marker for anal HPV 16 detection and anal dysplasia.