Among women over the age of 30 who test positive for a high-risk type of human papillomavirus (HPV) but have no apparent cervical abnormalities, a repeat HPV test two years later provides information about cervical cancer risk: women with an HPV infection that persists have a substantially increased risk for cervical cancer. These results were published in the Journal of the National Cancer Institute.
Each year in the United States, there are more than 12,000 new cases of cervical cancer and more than 4,000 deaths from the disease. Most cases of cervical cancer are caused by persistent infection with a high-risk type of HPV. The types of HPV that are linked with cervical cancer are transmitted sexually, and are extremely common. Most HPV infections clear on their own, but some persist and increase cancer risk.
For women age 30 or older, HPV tests are commonly used in combination with Pap tests for cervical cancer screening. The combination of HPV testing and Pap testing is not routinely used in younger women because many young women will have HPV infections that will clear on their own without causing cervical abnormalities. HPV testing may also be used for the further evaluation of an indeterminate Pap test result. This use of HPV testing is appropriate for women of all ages.
To explore how risk of cervical cancer varies by HPV test result and persistence of HPV infection, researchers in Taiwan conducted a study among more than 10,000 women between the ages of 30 and 65 years who had no evidence of cervical abnormalities at the start of the study.
Study participants had an HPV test at the start of the study and again two years later. Women were considered to have a persistent HPV infection if they tested positive for the same type of HPV at both examinations.
- Women with persistent HPV infections had the highest risk of cervical cancer: 12.4% developed cervical cancer over a 16-year period. In contrast, risk of cervical cancer was very low (0.14%) among women who tested negative for HPV at both visits.
- Older women with a persistent HPV infection had a higher risk of cervical cancer than younger women with a persistent HPV infection.
These results suggest that for women age 30 or older with a positive HPV test and normal Pap test results, a repeat HPV test to detect persistent infection can provide important information about cervical cancer risk.
Reference: Chen H-C, Schiffman M, Lin C-Y et al. Persistence of type-specific human papillomavirus infection and increased long-term risk of cervical cancer. Journal of the National Cancer Institute. Early online publication September 6, 2011.