Performance of HPV Testing vs. Cytology for Cervical Cancer Screening in Senegal

Thesis (Master's)--University of Washington, 2012Objective: To examine the performance of stand-alone and combined screening tools for the identification of cervical intraepithelial neoplasia grades 2 or 3, carcinoma in-situ, or invasive cervical cancer (CIN2+) in women in Senegal. Methods: Since 1997, we collected HIV serology, high risk HPV (HR-HPV) PCR testing, and cytologic evaluation for 3,120 women presenting to one of three outpatient clinics in Dakar, Senegal. Cervical biopsy was performed on 1,100 patients, and these results were then extrapolated to the remaining study population. Results: Overall, 10.7% of the patients tested positive for HIV. HR-HPV testing was positive in 29.9% of patients, and cytology was abnormal in 19.6% of patients. After extrapolation of biopsy results for HIV negative patients, the sensitivity of HR-HPV testing alone for detecting CIN2+ was estimated to be 67.4%, with a specificity of 81.8%, and PPV of 10.0%. A single cytologic evaluation had a sensitivity of 77.9%, a specificity of 90.1%, and a PPV of 24.0%. In the HIV positive population, the sensitivity of HR-HPV testing was 93.3%, the specificity was 30.5%, and the PPV was 18.4%. The sensitivity of cytologic evaluation was 85.8%, the specificity was 55.5%, and the PPV was 35.5%. This could be compared to triaging HIV positive patients with HR-HPV testing, then performing cytology on those who tested positive, which would yield a sensitivity of 86.3%, a specificity of 47.4%, a PPV of 35.8%. Conclusions: Our data suggests that particularly in HIV positive patients, triage using HR-HPV testing, followed by cytology in those who are positive, may be promising