In a modeling study reported in The Lancet, Brisson et al in the World Health Organization (WHO)-sponsored Cervical Cancer Elimination Modelling Consortium (CCEMC) found that high human papillomavirus (HPV) vaccine uptake in girls could lead to cervical cancer elimination in most low-income and lower-middle–income countries by the end of the century. Their findings suggested that the addition of high-uptake screening would hasten reductions in the incidence of cervical cancer and will be necessary to eliminate disease in those countries with the highest burden of disease.
Study Details
The study involved three models for projecting reductions in cervical cancer incidence in 78 lower-middle–income countries: girls-only vaccination; girls-only vaccination and once-lifetime screening; and girls-only vaccination and twice-lifetime screening.
In the models, girls were vaccinated at age 9 years (with catch-up to age 14 years), assuming a 90% coverage rate and 100% lifetime protection against HPV types 16, 18, 31, 33, 45, 52, and 58. Cervical screening consisted of HPV testing once or twice per lifetime at ages 35 years and 45 years, with uptake increasing from 45% in 2023 to 90% in 2045 and thereafter.
The elimination thresholds examined in the models were an average age-standardized cervical cancer incidence of ≤ 4 cases per 100,000 women-years and ≤ 10 cases per 100,000 women-years and a ≥ 85% reduction in disease incidence.
Model Predictions
Girls-only HPV vaccination was predicted to reduce the median age-standardized cervical cancer incidence from 19.8 to 2.1 cases per 100,000 women-years by the next century (89.4% reduction) and to prevent 61.0 million cases during this period. The addition of twice-lifetime screening further reduced the incidence to 0.7 cases per 100,000 women-years (96.7% reduction) and prevented an additional 12.1 million cases.
Girls-only vaccination was predicted to result in elimination in 60% of lower-middle–income countries on the elimination threshold of ≤ 4 cases per 100, 000 women-years, in 99% on the threshold of ≤ 10 per 100,000 women-years, and in 87% based on the ≥ 85% reduction threshold.
The addition of twice-lifetime screening predicted elimination in 100% of lower-middle–income countries for all three elimination thresholds.
In regions where all countries could achieve elimination with girls-only vaccination, elimination could occur between 2059 and 2102, depending on threshold and region. The addition of twice-lifetime screening could hasten elimination by 11 to 31 years.
The investigators concluded: “Predictions were consistent across our three models and suggest that high HPV vaccination coverage of girls can lead to cervical cancer elimination in most [lower-middle–income countries] by the end of the century. Screening with high uptake will expedite reductions and will be necessary to eliminate cervical cancer in countries with the highest burden.”
Marc Brisson, PhD, of Centre de recherche du CHU de Quebec, is the corresponding author for The Lancet article.
Disclosure: The study was funded by WHO, the United Nations (UN) Development Programme, UN Population Fund, the UN Children’s Fund–WHO–World Bank Special Program of Research, Development, and Research Training in Human Reproduction, and others. For full disclosures of the study authors, visit thelancet.com.
