Human Papillomavirus (HPV) and Cervical Cancer
More than 20 years of epidemiologic research by DCEG investigators has helped to establish the central causal role of carcinogenic genotypes of human papillomavirus (HPV) in the development of virtually all cases of cervical cancer. NCI’s natural history studies have shown that it is persistent HPV infection, and not the infection itself, that increases the risk of developing cervical cancer. This finding led to the creation and adoption of new screening guidelines by the American Cancer Society and the Association of Clinical Obstetricians and Gynecologists.
NCI scientists also developed and validated HPV DNA testing that directly assays the causal virus. Now in widespread use in the U.S., the test provides greater accuracy than ambiguous Pap smears, and has led to improved clinical management strategies, with lengthened screening intervals. In addition, NCI scientists invented the virus-like particle technology that enabled the development of HPV vaccines to prevent infection and resultant cancer. An NCI-sponsored Phase III clinical trial to evaluate the efficacy of a vaccine against HPV types 16 and 18 has shown near complete protection against new infections and precancerous lesions. As a result of NCI research, the U.S. strategy for the prevention of cervical cancer has been transformed from reliance on untargeted, frequent, and lifelong repetition of Pap smears to a combination of vaccination and targeted HPV-based screening.