Background: Prospective data on the risks of cervical precancer associated with specific human papillomavirus (HPV) genotypes are limited.
Methods: In 5060 women participating in the Atypical Squamous Cells of Undetermined Significance/Low-Grade Squamous Intraepithelial Lesions Triage Study (ALTS), we determined the cumulative 2-year risks of cervical intraepithelial neoplasia (CIN) grade 2 or more severe (> or =CIN2) and of grade 3 or more severe (> or =CIN3) for 38 individual HPV genotypes, as detected by polymerase chain reaction.
Results: The most common HPV genotypes detected at baseline, in descending order of prevalence, were 16, 52, 51, 31, 18, 53, 39, 56, 62, 59, and 58. When detected as a single-type HPV infection, HPV-16 had a 2-year cumulative risk of 50.6% (95% confidence interval [CI], 44.1%-57.2%) for > or =CIN2 and 39.1% (95% CI, 32.9%-45.7%) for > or =CIN3. For other singly detected carcinogenic HPV types, the risk of > or =CIN2 ranged from 4.7% (for HPV-59) to 29.5% (for HPV-31), and the risk of > or =CIN3 ranged from 0.0% (for HPV-59) to 14.8% (for HPV-31). Multiple infections with HPV genotypes of different risk classes resulted in a risk that was similar to, and not significantly different from, the risk observed for the HPV genotype of the highest risk class.
Conclusions: Genotype-specific HPV testing may be useful for identifying women with atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesions who are at higher and lower risk of prevalent and incipient cervical precancer.