2008 Issue 10
Allan Hildesheim, Ph.D.
Division of Cancer Epidemiology and Genetics
National Cancer Institute
With licensure of the first prophylactic human papillomavirus (HPV) vaccines, a new era in cervical cancer prevention has begun. The new vaccines add to the existing arsenal of prevention tools that can be used in efforts to reduce the cervical cancer burden worldwide.
However, fulfilling its potential to significantly impact cervical cancer rates — especially in the developing world, where the need is greatest — will depend on the rational use of resources now available to us.
In addition to the virus-like particle-based HPV vaccines, which were designed to prevent HPV infections before they occur, other prevention tools include cytology-based screening programs (conventional Pap smear and more recently developed liquid-based cytology screening), HPV DNA diagnostic tests (used as an adjunct to cytology screening or as a primary screen), and visual screening methods (mainly in areas where alternative methods are not feasible) (1-4).
In countries where effective screening programs are in place, including the United States and parts of Europe, screening programs have led to important declines in the rate of cervical cancer incidence and mortality (5,6). In these countries, screening remains an essential method for the prevention of cervical cancer. Screening in these countries will remain important even after the introduction of HPV vaccination because, unlike the prophylactic HPV vaccines that target two carcinogenic HPV types (HPV types 16/18), screening programs are designed to detect all precancerous cervical lesions regardless of the HPV type involved, and therefore have broader coverage than vaccination programs could hope to achieve. Within high resource countries with established screening programs, one notable area where vaccination might contribute to further reductions in cervical cancer rates is through concerted efforts to vaccinate underserved populations who have historically failed to benefit from existing cervical cancer screening programs (7).