A study conducted at the UK’s largest HIV treatment centre suggests that HIV-positive men who are infected with anal human papilloma virus (HPV), and have abnormal cells in the anus, are usually infected with multiple HPV strains, which are often carcinogenic. This finding, reported in the November 7th edition of AIDS, stands in contrast to research into HPV infection and cervical cancer which found that infection with multiple strains of HPV was rare in women.
Investigators at the Chelsea and Westminster Hospital in London analysed the HPV types in 18 HIV-positive men with anal intra-epithelial neoplasma.
Single HPV infection was only seen in one patient, double infection was observed in two patients, triple infection in three patients, and 50% of individuals were infected with four or more types of HPV. One patient with stage II anal intra-epithelial neoplasia was infected with seven different HPV types, including types 16 and 33, which are high risk for the development of cancer. The patient experienced spontaneous regression over six months, however, in the absence of changes in viral load or CD4 cell count.
The investigators suggest that these findings indicate that data on cervical cancer may not be extrapolated to anal cancer, and that vaccination strategies to prevent HPV-related cervical cancer may not be successful against anal cancers.
Further information on this website
Genital warts - factsheet
Human papilloma virus - overview
Vaccines against herpes and HPV on their way - news story
Anal cancer risk high in all HIV-positive men regardless of sexual behaviour - news story
Stebbing J et al. Multiple human papillomavirus types appear to be a feature of anal not cervical intra-epithelial neoplasia. AIDS 17: 2401, 2003.