Anal cancer risk high in all HIV-positive men regardless of sexual behaviour

Edwin J. Bernard
Estimated reading time 2 minutes
This article is more than 22 years old.

Infection with human papillomavirus (HPV) - the virus associated with both vaginal and anal cancer - as well as pre-cancerous lesions, have been found in a significant number of HIV-positive men who have never had anal intercourse, according to researchers from Hôpital Européen Georges Pompidou outpatient clinic in Paris.

Until now it was assumed that HPV was acquired sexually through receptive anal intercourse. But a cross-sectional study of 50 HIV-positive heterosexual male injection drug users (IDU) with no history of anal intercourse and 67 HIV-infected men who had sex with men (MSM) found surprisingly high levels of HPV infection as well as low- and high-grade pre-cancerous lesions (anal squamous intraepithelial lesions or SIL) in the IDU group.

The researchers found that 46% of the heterosexual IDUs were infected anally with HPV. Low-grade SIL was found in 16% and high-grade SIL in 18%. As suspected, anal HPV infection was found 85% of MSM, low-grade SIL in 49% and high-grade SIL in 18%.

Glossary

human papilloma virus (HPV)

Some strains of this virus cause warts, including genital and anal warts. Other strains are responsible for cervical cancer, anal cancer and some cancers of the penis, vagina, vulva, urethra, tongue and tonsils.

squamous intraepithelial lesion (SIL)

This term is used to describe the detection of abnormal cells that have been ‘transformed’ by HPV into a possibly pre-cancerous state. According to the degree of cell change this will be called low-grade or high-grade SIL (LSIL or HSIL). If SIL is detected, a colposcopy will usually be ordered.

lesions

Small scrapes, sores or tears in tissue. Lesions in the vagina or rectum can be cellular entry points for HIV.

IDU

Injecting drug user.

cross-sectional study

A ‘snapshot’ study in which information is collected on people at one point in time. See also ‘longitudinal’.

Risk factors associated with low- or high-grade SIL amongst IDUs included CD4+ cell counts below 250 cells/mm3, viral load greater than 1.7 log10 copies/mL, a previous AIDS illness and anal HPV detection.

Risk factors among MSM included having anal intercourse with more than 10 partners over a lifetime, and anal HPV detection.

The researchers conclude that “anal HPV infection and anal SIL may be acquired in the absence of anal intercourse in HIV-positive men” and suggest that “all HIV-positive men with CD4+ cell counts less than 500 cells/mL, regardless of history of anal intercourse, should be considered for anal cytologic screening,” otherwise known as anal pap smears.

When caught early, anal cancer is completely preventable. It is currently one of the three most common non-AIDS defining illnesses amongst HIV-positive MSM.

Regular anal pap smears for HIV-positive males was recommended last year by Joel Palefsky - one of this study’s co-authors - but, as yet, no HIV clinic in the UK carries this out. For more about HPV and anal cancer , see the September 2002 issue of ATU, available here.

References

Piketty C et al. High prevalence of anal human papillomavirus infection and anal cancer precursors among HIV-infected persons in the absence of anal intercourse. Ann Intern Med 138:453–459, 2003.

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