Infection with multiple human papillomavirus (HPV) genotypes and risk of pre-cancerous cervical abnormalities

This study is the first prospective analysis using multiple measurements longitudinally of viral and lesion endpoints to investigate the
relationship between infection with multiple human papillomavirus (HPV) genotypes (types for short) and risk of pre-cancerous cervical abnormalities. The authors concluded that the risk for developing precursor lesions is much higher for women infected with multiple HPV types than for those infected by a single type. The excess risks for multiple-type infections remained after exclusion from the analysis of women infected with HPV-16, of those infected with high-risk HPV types, or with persistent infections, particularly for squamous intraepithelial lesions of all grades. Coinfections involving HPV-16 and HPV-58 seemed particularly prone to increase risk. 

These findings have implications for the management of women with HPV infections. Women who harbor infections with multiple HPV types either concurrently, at a single point in time, or sequentially over periods ranging from a few months to more than one or two years should be followed more closely.  Further research should help elucidate whether this finding represents a direct synergistic effect of multiple types on cervical carcinogenesis or simply a reflection of lowered immune function in some women, which would prevent them from clearing individual infections effectively.

Bibliographic reference:

Trottier H et al.: "Human papillomavirus infections with multiple types and risk of cervical neoplasia", Cancer Epidemiol Biomarkers Prev. 2006 Jul;15(7):1274-80

Helen Trottier

Division of Cancer Epidemiology, McGill University, Montreal, Canada