Evidence-Based, Alternative Cervical Cancer Screening Approaches in Low-Resource Settings

Article excerpt

Cervical cancer kills approximately 270,000 women worldwide each year, with nearly 85% of those deaths occurring in resource-poor settings. (1) Use of the Pap smear for routine screening of women has resulted in a dramatic decline in cervical cancer deaths over the past lour decades in wealthier countries. A key reason for continuing high mortality in the developing world is the shortage of efficient, high-quality screening programs in those regions.

In 1999, five international health organizations came together to create the Alliance for Cervical Cancer Prevention (ACCP). * For the next eight years, with support from the Bill & Melinda Gates Foundation, the partners worked on a coordinated research agenda aimed at assessing a variety of approaches to cervical cancer screening and treatment (especially ones that may be better suited to low-resource settings), improving service delivery systems, ensuring that community perspectives and needs are incorporated into program design, and increasing awareness of cervical cancer and effective prevention strategies. Several outstanding issues were identified at that time. A general issue was a lack of consensus about the most effective and feasible options for improving cancer screening and treatment. Specific issues included uncertainty about the impact of simple screening methods and a screen-and-treat approach on cervical cancer incidence and mortality; the comparative performance of visual inspection methods of screening--visual inspection with acetic acid (VIA) or Lugol's iodine [(VILI).sup./]--and new methods using human papillomavirus (HPV) DNA testing; the optimal ways to reduce false-positive results from visual inspection methods without producing more false-negatives; and any possible links between the use of cryotherapy and subsequent HIV acquisition.

Recent studies and analyses have answered some of these questions and have validated earlier findings related to safe, effective, operationally feasible and culturally appropriate strategies for secondary prevention of cervical cancer. [double dagger] On the basis of these new data and the results of earlier research conducted in 20 African, Asian and Latin American countries, the ACCP partners have summarized and shared key findings and recommendations for effective cervical cancer screening and treatment programs in low-resource settings, as follows.

FINDINGS

* In low-resource settings, the optimal age-group for cervical cancer screening to achieve the greatest public health impact is 30-39-year-olds. Screening is considered optimal when the smallest amount of resources is used to achieve the greatest benefit. To determine the optimal age for cervical cancer screening, ACCP researchers used two methodologies: modeling and field-based study. Goldie et al. (2) conducted cost-effectiveness modeling comparing screening strategies in five developing countries. Their model predicted that for 35-year-old women screened only once in their life, a single-visit or two-visit approach with the VIA method could reduce the lifetime risk of cervical cancer by 25% and HPV DNA testing could reduce it by 36%. (In a single-visit approach, women are screened and treated during the same visit, reducing loss to follow-up; in a two-visit approach, women must return for results and treatment at some time after screening.) Screening women twice, at ages 35 and 40, was predicted to reduce lifetime cancer risk by 65% (with VIA) or 76% (with HPV DNA testing). The model estimated that the cost per life-year saved with these approaches would be less than each country's per capita gross domestic product, making them highly cost-effective according to standards set by the World Health Organization's Commission on Macroeconomics and Health. (3)

Sankaranayananan et al. (4) followed more than 49,000 women aged 30-59 in India for seven years after a single round of VIA screening, with treatment provided as indicated, and found that the intervention had the greatest impact among women in their 30s. …