Evaluation of cervical visual inspection screening in Dar es Salaam, Tanzania

Abstract

Objective To evaluate the feasibility and performance of screening for cervical cancer using visual inspection with acetic acid (VIA) or with Lugol's iodine (VILI) in Dar es Salaam, Tanzania. Methods The accuracy of tests for detecting cervical intraepithelial neoplasia (CIN) was assessed in a cross-sectional study of 10 378 women. All women who were screened underwent colposcopy, and biopsies were offered to those with abnormal colposcopy results. Results The positivity rates were 3.8% for VIA and 4.8% for VILI. The peak positivity rates for both visual tests were observed just after training or re-training and gradually declined thereafter. CIN 1 was diagnosed in 41 women, CIN 2–3 in 33 women, and invasive cancer in 200 women, showing high detection rates of invasive cancer. The sensitivity and specificity for the detection of CIN 2–3 lesions were 60.6% (95% confidence interval [CI], 42.1–77.1) and 98.2% (95% CI, 97.9–98.4), respectively, for VIA; and 93.9% (95% CI, 79.8–99.3) and 97.3% (95% CI, 97.0–97.6), respectively, for VILI. Two-thirds of the women detected with CIN 2–3 lesions were treated. Conclusion Both visual screening tests are useful and accurate, especially in low-income settings. Standardization of assessment of the visual inspection techniques, continual training and supervision, and quality control measures are important for successful visual screening programs.