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Cervical cancer is the main cancer among women in sub-Saharan Africa, India and other parts of the developing world. Evaluation of screening performance of effective, feasible and affordable early detection and management methods is a public health priority. Five screening methods, naked eye visual inspection of the cervix uteri after application of diluted acetic acid (VIA), or Lugol's iodine (VILI) or with a magnifying device (VIAM), the Pap smear and human papillomavirus testing with the high-risk probe of the Hybrid Capture-2 assay (HC2), were evaluated in 11 studies in India and Africa. More than 58,000 women, aged 25-64 years, were tested with 2-5 screening tests and outcome verification was done on all women independent of the screen test results. The outcome was presence or absence of cervical intraepithelial neoplasia (CIN) of different degrees or invasive cervical cancer. Verification was based on colposcopy and histological interpretation of colposcopy-directed biopsies. Negative colposcopy was accepted as a truly negative outcome. VIA showed a sensitivity of 79% (95% CI 73-85%) and 83% (95% CI 77-89%), and a specificity of 85% (95% CI 81-89%) and 84% (95% CI 80-88%) for the outcomes CIN21 or CIN31, respectively. VILI was on average 10% more sensitive and equally specific. VIAM showed similar results as VIA. The Pap smear showed lowest sensitivity, even at the lowest cutoff of atypical squamous cells of undetermined significance (57%; 95% CI 38-76%) for CIN21 but the specificity was rather high (93%; 95% CI 89-97%). The HC2-assay showed a sensitivity for CIN21 of 62% (95% CI 56-68%) and a specificity of 94% (95% CI 92-95%). Substantial interstudy variation was observed in the accuracy of the visual screening methods. Accuracy of visual methods and cytology increased over time, whereas performance of HC2 was constant. Results of visual tests and colposcopy were highly correlated. This study was the largest ever done that evaluates the cross-sectional accuracy of screening tests for cervical cancer precursors in developing countries. The merit of the study was that all screened subjects were submitted to confirmatory investigations avoiding to verification bias. A major finding was the consistently higher sensitivity but equal specificity of VILI compared with VIA. Nevertheless, some caution is warranted in the interpretation of observed accuracy measures, since a certain degree of gold standard misclassification cannot be excluded. Because of the correlation between visual screening tests and colposcopy and a certain degree of over-diagnosis of apparent CIN21 by study pathologists, it is possible that both sensitivity and specificity of VIA and VILI were overestimated. Gold standard verification error could also explain the surprisingly low sensitivity of HC2, which contrasts with findings from other studies. ' 2008 Wiley-Liss, Inc.Key words: cervical cancer; cervical intraepithelial neoplasia; screening methods; VIA; pap smear; HPV; developing countries Cervical cancer, an eminently preventable can...

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Objective To assess the feasibility of sustaining visual cervical screening and treatment services in Mali, and to evaluate their performance and impact in improving the provision of cervical cancer control, following an initial cross-sectional study.Design Descriptive study.Setting Bamako area, Mali.Population Women aged 30-59 years.Methods Routine visual screening and treatment services were organised through two hospitals and 14 health centres. Patients with positive visual screening tests underwent colposcopy and/or directed biopsies, and ablative or surgical excision treatment was offered to those with cervical intraepithelial neoplasia (CIN).Main outcome measures Test positivity, detection and treatment rates for CIN and the sustainability of screening services.Results Of the 14 141 women screened, 1682 (11.9%) were positive and were referred for further investigations and treatment. Over 75% of the screen-positive women underwent colposcopy and/or biopsy. CIN 1 was detected in 383 women, CIN 2 in 88, CIN 3 in 37 and invasive cervical cancer in 497. More than 80% of women with CIN and 35% of those with invasive cancer received treatment. The test performance characteristics and treatment coverage of routine screening were similar to those observed in the preceding cross-sectional study.Conclusion Visual screening and treatment services are sustainable and effective in improving cervical cancer control provision by health services in Bamako, Mali. It is essential to organise and sustain several point-of-care services in order to extend cervical cancer prevention in low-income African countries.

Objective The performance of colposcopy provided in a screening study in five African countries was evaluated.Design Cross-sectional study.Setting Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.Population Women aged 25-59 years.Methods A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.Main outcome measures Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).Results Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90-100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.Conclusions The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa.