Pursuing Eradication of Cervical Cancer Through Preventive Interventions

Through rapid expansion of current interventions, the majority of countries could see an end to cervical cancer as a public health problem, according to a statistical trends analysis and modelling study. However, while human papillomavirus (HPV) vaccines and cervical screening tests have been utilized in the majority of high-income countries to combat cervical cancer, low- to middle-income countries (LMICs) are left with little to no access to these preventive solutions.

The study, published in The Lancet Oncology, predicted that as many as 13.4 million cases of cervical cancer could be averted by 2069 by rapidly increasing rates of HPV-based cervical screening and the volume and uptake of HPV vaccines. Utilization of these measures is estimated to have the capability to drop the rates of cervical cancer under the rare cancer threshold of 6 cases per 100,000 per year, or even lower to 4 cases per 100,000 per year.

“If high coverage vaccination can be implemented quickly, a substantial effect on the burden of disease will be seen after 3 to 4 decades, but nearer-term impact will require delivery of cervical screening to older cohorts who will not benefit from HPV vaccination,” explained the authors.

In a slower paced scale-up of current interventions, the eradication of cervical cancer is estimated for countries with high to very high human development indexes (HDIs) by 2100. However, prevalence rates would remain above the target threshold for medium HDI countries at 4.4 per 100,000 and low HDI nations at 14 per 100,000.

“These existing trends in cervical cancer incidence must be taken into account when considering the impact of future interventions,” the authors acknowledged. “The long-term interplay of these factors with the time-delayed effects of vaccination, and the potential benefit of screening or adult HPV vaccination in hastening preventive effects, are not well understood.”

Alternatively, if intervention techniques remain constant and fail to become more widely accessible, the modelling study predicts as many as 44.4 million cervical cancer cases would be diagnosed over a 50-year span, with nearly 67% emerging in low- or medium-HDI countries, resulting in an estimated 15 million deaths. This would raise the worldwide number of annual cases from nearly 600,000 in 2020 to 1.3 million in 2069, accounting for population growth and aging.

Implementing a rapid scale-up of preventive interventions would take a global commitment and an abundance of resources.

“There are cultural, logistical, and financial barriers to scaling up cervical screening coverage in many settings, and providing access to screening tests and quality colposcopy, pathology, and precancer treatment procedures can present a substantial challenge,” wrote the authors.

The director general of the World Health Organization called for the elimination of cervical cancer as a public health problem in 2018. The goal was planned to be achieved through utilization of scaled-up vaccination, more frequent screening practices, treatment of precancers, early detection and prompt treatment of early invasive cancers, and palliative care.

With 570,000 new cases diagnosed worldwide in 2018, cervical cancer stands as the fourth most common cancer in women with 85% of these diagnoses occuring in LMICs with low HDIs. Encompassing a group of more than 150 viruses, HPV is responsible for the majority of cervical cancers. It is estimated that between 84% and 90% of cervical cancer could be prevented by screening tests, treating cervical precancers, and the use of broad-spectrum HPV vaccines.

While screening tests and HPV vaccination have been implemented in most high-income countries to reduce the prevalence of cervical cancer, LMICs lack the capability to obtain the resources necessary to progress toward achieving the goal of eliminating the disease as a public health problem by 2100. Only a rapid, global scale-up of vaccination distribution and screening tests could achieve the best possible results the modeling study has projected.

“Despite the enormity of the problem, our findings suggest that global elimination is within reach with tools that are already available, provided that both high coverage of HPV vaccination and cervical screening can be achieved,” Karen Canfell, DPhil, director of the Cancer Research Division at the Cancer Council New South Wales, said in a statement.

Reference

Simms KT, Steinberg J, Caruana M, et al. Impact of scaled up human papillomavirus vaccination and cervical screening and the potential for global elimination of cervical cancer in 181 countries, 2020—99: a modelling study [published online February 19, 2019]. Lancet Oncol. doi: 10.1016/ S1470-2045(19)30072-5.