Cervical Cancer Prevention

Abstract

CERVICAL CANCER IS UNIQUE FOR SEVERAL REASONS. It has recognized, well-described risk factors; there is an identifiable precancerous condition; the transition from precancer to cancer occurs over an extended period (10 years on average); screening tests for detecting cancer and precancer exist; and outpatient treatments for precancer are safe, effective, and relatively inexpensive. Cervical cancer is also a rare, but confirmed, sequela of a sexually transmitted, high-risk human papillomavirus infection. Each year almost 500 000 new cases of cervical cancer are diagnosed and 230 000 deaths occur, 80% of which are in low-resource countries. Thus, more deaths result from human papillomavirus infection and cervical cancer than from sequelae of all other sexually transmitted infections combined, with the recent exceptions of human immunodeficiency virus (HIV) and AIDS. Although the Papanicolaou test was developed almost 80 years ago, and cytology-based screening programs were initiated more than 50 years ago, cervical cancer still remains the principal cause of cancer deaths among women in developing countries. Even in developed countries, despite long-standing screening programs and technological improvements in both cytological (Papanicolaou) screening and outpatient treatment of precancer that have reduced the burden of disease, elimination of this preventable cancer remains elusive. Simply put, the majority of cervical cancer cases worldwide occur among women who are never screened or treated. These women tend to be from mostly low-income groups or have other characteristics that place them at highest risk for disease, such as early sexual debut (age 20 years), high parity ( 4 live births), and a history of multiple sexual partners ( 5). Although cervical cancer screening has received much emphasis and refinements in screening tests render them ever more accurate, screening alone has no intrinsic preventive value. It is only when a positive test result is linked to treatment that disease prevention can occur. Indeed, it is telling that many regional and national programs are called cervical cancer screening as opposed to prevention programs. In developed countries, cervical cancer “screening” programs commonly mandate multiple, separate visits for screening, confirmation, diagnosis, and treatment. As might be expected, the higher the number of visits required to complete the process, the more likely the cancer prevention loop will not be closed. Three articles published in this issue of JAMA provide new and practical insights into how cervical cancer prevention efforts could be improved among women at highest risk for disease. The studies by Denny and colleagues and by Brewster and colleagues primarily address never screened or underscreened women who have a relatively high (prior) probability of disease. These reports focus on approaches to strengthen the critical link between testing and treatment of patients with positive test results in settings with higher disease prevalence. In the third article in this issue, Sawaya discusses clinical protocols applied to women with relatively low (prior) probability of disease and focuses on how to improve the clinical utility of testing in a relatively low-risk (or incident disease) population. The themes of program practicality, focusing on high-risk groups, and developing better and more appropriate links between screening and treatment are common features of these 3 articles. Working with a high-risk, largely Latina population in Southern California, Brewster et al recognized that cervical cancer prevention was severely limited by the mandates of a diagnosis-oriented, multiple-visit approach. In conceptualizing their approach, they emphasize that in a time when treatment of precancerous lesions is available, it is unacceptable for women to develop this disease. The results of their randomized trial testing the feasibility and acceptability of a single-visit program demonstrate that pro-