Cervical cancer screening in high- and low-resource countries: implications and new developments.

The implementation of cytology-based screening programs for precancerous lesions of the cervix has decreased the incidence of and mortality from cervical cancer in much of the developed world. Countries without the resources to install such frequent and laboratory-dependent screening programs have more and more options at their disposal. A screening program based on cytology analysis requires too much training, infrastructure, and repeated screening to be feasible. Visual inspection with acetic acid, often used throughout the world, is inexpensive and both sensitive and specific, but it lacks reproducibility. Although human papillomavirus (HPV) testing is too expensive for widespread use, its negative predictive value and sensitivity make it a promising method of screening. Utilizing HPV vaccines as a primary mode of prevention may not be financially feasible and does not obviate the need for screening. Cervical cancer has been considered an AIDS-defining illness, with HPV and HIV often coexisting, and screening methods have been shown to be as reliable for women with HIV as those without. Ultimately, the most clinically effective and cost-effective methods for reducing cervical cancer incidence are those that limit the number of visits that women are required to attend. Providing immediate cryotherapy for those with a positive screen, whether by visual inspection or HPV testing, is promising to have quite an impact, although the type of program implemented will depend on the needs and expectations of each country.