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Background: HIV infection is associated with a higher incidence of precancerous cervical lesions and their progression to invasive cervical cancer (ICC). Zambia is a global epicenter of HIV and ICC, yet the overall burden of cervical pre-cancer [cervical intraepithelial neoplasia 3 (CIN3)] and ICC among its HIV positive adult female population is unknown. The objective of this study was to determine the burden of cervical disease among HIV positive women in Zambia by estimating the number with CIN3 and ICC. Methods: We conducted a cross-sectional study among 309 HIV positive women attending screening in Lusaka (Zambia's most populated province) to measure the cervical disease burden by visual inspection with acetic acid enhanced by digital cervicography (DC), cytology, and histology. We then used estimates of the prevalence of CIN3 and ICC from the cross-sectional study and Spectrum model-based estimates for HIV infection among Zambian women to estimate the burden of CIN3 and ICC among HIV positive women nationally. Results: Over half (52 %) of the study participants screened positive by DC, while 45 % had cytologic evidence of high grade squamous intraepithelial lesions (SIL) or worse. Histopathologic evaluation revealed that 20 % of women had evidence of CIN2 or worse, 11 % had CIN3 or worse, and 2 % had ICC. Using the Spectrum model, we therefore estimate that 34,051 HIV positive women in Zambia have CIN3 and 7,297 have ICC. Conclusions: The DC, cytology, and histology results revealed a large cervical disease burden in this previously unscreened HIV positive population. This very large burden indicates that continued scale-up of cervical cancer screening and treatment is urgently needed. [ABSTRACT FROM AUTHOR]

Background The most common human papillomavirus (HPV) genotypes isolated from cervical cancer in select African countries are HPV-16, HPV-18, HPV-35, and HPV-45, but the most common genotypes in Zambia are unknown. The overall objective of this study was to assess the potential impact of current HPV vaccines in preventing cervical cancer in Zambia, by determining the combined prevalence of HPV-16 and/or HPV-18 in invasive cervical cancer (ICC) and high-grade pre-cancer [cervical intraepithelial neoplasia 2 or 3 (CIN2/3)] cases. Findings We compared DNA extraction techniques to determine which assay performs well in the Zambian context, where unbuffered formalin is used to fix specimens. We then tested specimens with the Abbott RealTime High-Risk HPV test to estimate the prevalence of HPV-16/18 in formalin-fixed, paraffin-embedded ICC and CIN2/3 specimens. DNA extraction using heat (without xylene) was more successful than xylene-based extraction. Over 80% of specimens tested using heat extraction and the Abbott RealTime HPV test were positive for HPV. HPV-16 and/or HPV-18 were identified in 65/93 (69.9%) ICC specimens positive for HPV and in 43/65 (58.5%) CIN2/3 specimens positive for HPV. Conclusions To our knowledge this is the first report to identify HPV genotypes in cervical cancers in Zambia. A combined HPV-16/18 prevalence of 69.9% in ICC specimens suggests that current vaccines will be highly protective against cervical cancer in Zambia. [ABSTRACT FROM AUTHOR]