Monday 29 July 2013
Research is showing a number of rising concerns surrounding the risk of anal cancer in gay and bisexual men.
It may not be at top of the mind of the average gay Kiwi male, but the New Zealand AIDS Foundation (NZAF) warns that anal cancer is likely to be the next big health concern for gay and bisexual men.
Human Papilloma Virus (HPV) is the leading cause of anal cancer in that population and new research is showing incidences of exposure to HPV are more common than previously thought.
Passed on through sexual contact, a persistent HPV infection can lead to changes in anal cells which can in turn lead to cancer. HPV can also cause penile cancer, cervical cancer in cis-women and oral cancers, as well as genital and anal warts.
However correct and consistent condom use does reduce the risk of sexually transmitted HPV by around 50 percent.
NZAF Executive Director Shaun Robinson says that the Foundation is keeping a close eye on HPV research coming out of the STI and AIDS World Congress, which just concluded in Vienna. “We already know that HPV will feature strongly as a health issue in the future for gay and bi men. We also know that HIV acquisition may be increased by HPV infection, so on many levels this is of significant concern to us.”
Recent Australian studies show the rate of anal cancer is especially high among HIV-positive men at 100 cases per 100,000.
Research from the Royal Liverpool University Hospital, Homerton University Hospital and Chelsea and Westminster Hospital in the United Kingdom has found that gay men 26 years and under are 15 times more likely to suffer from genital cancers than heterosexual men.
Alarmingly and on an international scale, gay and bisexual men have rates of anal cancer that are higher than the rates of cervical cancer were before widespread cervical cancer screening programmes began.
New Zealand has had an HPV vaccination programme in place for young women since 2008 and currently funds the Gardasil vaccine for girls between the ages of 12 and 18 years. Gardasil protects against the two strongest strains of HPV that cause genital warts and the two most aggressive strains of HPV linked to anal and other cancers.
Heterosexual men are indirectly protected from HPV if they have sex with a woman who has been vaccinated, a concept known as ‘herd immunity’. Unlike heterosexual men, gay and bisexual men obtain no indirect benefit from the current HPV vaccination programme.
A HIV and public health researcher has strongly supported offering free HPV vaccination for gay men in New Zealand. This follows reports that the Pharmacology and Therapeutics Advisory Committee (PTAC) are considering extending coverage to males and listing young gay males from age 11 to 25 as a priority group.
Dr Peter Saxton said international data highlights the high prevalence of oncogenic HPV strains among gay men and an elevated prevalence of pre-cancerous anal lesions and cancer.
“The quadrivalent vaccine currently offered to young women protects against acquisition of four HPV strains, in particular against HPV 16, which is associated with anal cancer.
“There are serious health equity issues raised by having a vaccine that is this effective but not providing it to one of the highest need groups,” continues Saxton, “especially when gay men receive no indirect benefit through the vaccination of young women.”
He goes on to note: “Implementing vaccine uptake among very young gay men who don’t feel safe disclosing their sexuality is a challenge but also one that could be overcome by extending coverage to all young men.
“This is a cancer vaccine. Any approach to covering gay men will have its imperfections but we shouldn’t lose sight of the enormous public health benefits that are possible.”
The NZAF welcomes initiatives to provide HPV vaccination to gay and bisexual men. Robinson points out that Gardasil is a cancer vaccine as well as one that will significantly reduce the spread of genital warts which are currently the most common viral sexually transmitted infection (STI). “We have a very important opportunity here to improve the health of gay and bisexual men through public provision of this vaccine,” he says.
Gay and bisexual men can currently request the HPV vaccination through their local GP at a cost of around $450 and those interested in more information should contact their doctor.