Investigator
Gates Foundation
The impact of HIV on cervical cancer elimination in KwaZulu-Natal: a comparative modeling analysis
Abstract Background Achieving cervical cancer (CC) elimination requires addressing disparities in CC burden for women living with HIV (WLHIV) and how disparities evolve in the context of antiretroviral therapy (ART) scale-up. To inform CC elimination for high HIV prevalence regions, we modeled the impact of HIV, HIV interventions, and CC interventions in KwaZulu-Natal, South Africa. Methods We used 2 independently developed, dynamic compartmental transmission models of HIV and human papillomavirus (DRIVE and Policy1-Cervix-HIV) calibrated to KwaZulu-Natal. We simulated: a counterfactual without HIV but with observed CC screening and vaccination; and scenarios sequentially adding condom use and voluntary medical male circumcision (VMMC); HIV; observed HIV and CC interventions (status quo); achieving United Nations Programme on HIV/AIDS HIV treatment targets; and achieving World Health Organization (WHO) CC elimination targets. The impact of each scenario was measured as the difference in CC incidence from the previous scenario. Results were reported from 2024 to 2124 as a range between the 2 models; CC elimination was WHO-defined as incidence <4/100 000 women-years. Results For the status quo, CC incidence ranged from 61.30 to 78.96/100 000 women-years in 2024, with the highest incidence among WLHIV (126.8-192.0/100 000). HIV contributed an estimated 29.08-48.87 additional cases per 100 000. Neither model predicted elimination under status quo interventions, but achieving HIV treatment and CC elimination targets could reduce incidence to 1.42-6.25/100 000 women-years in 2124. Conclusions HIV is associated with a population-level increase in CC incidence. However, scaling up ART coverage and CC interventions is expected to significantly reduce the burden of CC overall and among WLHIV. These conclusions are consistent between both models and strengthened by the comparative modeling approach.
Modelling cervical cancer elimination using single‐visit screening and treatment strategies in the context of high HIV prevalence: estimates for KwaZulu‐Natal, South Africa
AbstractIntroductionIn settings with high HIV prevalence, cervical cancer incidence rates are up to six‐fold higher than the global average of 13.1 cases per 100,000 women‐years. To inform strategies for global cervical cancer elimination, we used a dynamic transmission model to evaluate scalable screening and treatment strategies, accounting for HIV‐associated cancer risks and weighing prevention gains against overtreatment.MethodsWe developed a dynamic model of HIV‐HPV co‐infection and disease progression, which we calibrated to KwaZulu‐Natal, South Africa. Our baseline scenario reflects the current practice of HPV vaccination with a multi‐visit screening and treatment strategy involving cytology and colposcopy triage. We evaluated 13 comparator scenarios with increased vaccination coverage and one‐time, two‐time or repeat HIV‐targeted cervical cancer screening with the following single‐visit strategies: HPV DNA testing, HPV genotyping, automated visual evaluation (AVE) and HPV DNA with AVE triage. In all scenarios, HIV antiretroviral therapy, condom use and voluntary male medical circumcision continue at baseline levels. We simulated cancer incidence under each scenario from 2020 to 2120 using the 25 best‐fitting parameter sets. We present the median and range of model output from these simulations to account for parameter uncertainty.ResultsWe estimate that cervical cancer incidence will decrease by 87% with the continuation of current cervical cancer and HIV prevention strategies, from an age‐standardized rate per 100,000 women of 80.4 (range 58.2, 112.1) in 2020 to 10.7 (4.2, 29.9) in 2120. Scenarios scaling up vaccination and single‐visit strategies resulted in near‐ and long‐term gains. With repeat HIV‐targeted screening, incidence rates were projected to be 29–34% lower in 2030 relative to the baseline scenario, and elimination (incidence <4/100,000) was achieved with HPV DNA testing in 2095 and with AVE in 2114. A strategy of HPV DNA with AVE triage optimized the tradeoff between cancer cases averted and overtreatment.ConclusionsSingle‐visit screening strategies could avert a substantial burden of cervical cancer and accelerate progress towards elimination in settings with a high burden of HIV. Increasing the screening frequency among women with HIV and reducing loss‐to‐follow‐up for treatment will be key components of a successful elimination strategy.
Modeling HPV Self-Sampling Impact on Cervical Cancer in East African Immigrants
Cervical cancer screening uptake among East African immigrants in the U.S. is low. Offering self-collected samples for human papillomavirus (HPV) testing increases screening coverage among underserved populations, but the potential impact on cervical cancer incidence and mortality is understudied. A Markov cohort state-transition model was used to predict the impact of primary HPV screening with self-sampling on cervical cancer incidence and mortality among East African immigrant women in Washington state. The model estimated cervical cancer cases and deaths for a hypothetical cohort from ages 25 to 80 years under alternative screening, diagnostic colposcopy and treatment scenarios. Base case scenarios compared primary HPV testing by clinician-sampling exclusively (standard of care) with self-sampling exclusively, assuming higher screening coverage (70% vs 63%) but lower colposcopy adherence with self-sampling (67% vs 83%) with equal treatment coverage of 85%, based on Washington state patient data. Sensitivity analyses with varied coverages, and also the combinations of the 2 strategies were evaluated. The model was developed and fitted between 2022 and 2024. In the base case scenario, an exclusive self-sampling strategy results in 4% higher cervical cancer incidence and mortality compared to the standard of care. Self-sampling results in lower cancer incidence and mortality if colposcopy adherence is raised to the level of the standard of care and/or if coverage is increased beyond 90%. In scenarios combining clinician- with self-sampling, the benefits of reaching more women with self-sampling are attenuated if more than 34% of screening is done by self-sampling. Self-sampling has the potential to improve cervical cancer prevention for underserved populations. The impact of the strategy can be enhanced with stronger linkage to follow-up care.
Validation of a Lab-free Low-cost Screening Test for Prevention of Cervical Cancer
The purpose of this study is to validate Automated Visual Evaluation (AVE), specifically the CINFinder version developed by DL Analytics, a point-of-care screening and triage diagnostic tool for cervical cancer based on the assessment of digital images through artificial intelligence. Several teams around the world have developed versions of AVE as a triage technology but none as a screening tool.
