The Global Health Challenge of Cervical Cancer

Cervical cancer is a leading cause of cancer death worldwide, but it is almost entirely preventable. Nearly all cervical cancers are caused by persistent infection with the human papillomavirus (HPV). There is a prolonged period between HPV infection and progression to cancer, creating two key opportunities to prevent cervical cancer in many women. Primary prevention is via HPV vaccination to prevent the initial HPV infection. Secondary prevention is via regular screening for cervical pre-cancer lesions, and the slow progression to cancer enables repeated screening and early treatment.

Neither form of prevention is commonly available in low- and middle-income countries (LMICs). Even when screening is available, there is low uptake, in part due to the stigma and lack of information associated with both cancer and women’s sexual and reproductive health.  Pap smears (for annual cytology-based screening) and cervical biopsies (to definitively diagnose cervical pre-cancer and cancer and to guide treatment) are effective in high-income countries but not commonly available in LMICs due to the lack of the necessary infrastructure and regular, periodic screening needed. Cervical cancer disproportionately affects women in LMICs for all these reasons.

Screening in LMICs, when available, is typically by visual inspection of the cervix at a PHC facility (by a method known as VIA, visual inspection with acetic acid). This can trigger a decision to treat cervical pre-cancer lesions. Because this method has poor sensitivity and specificity, it can result in both under- and over-treatment. WHO guidelines recommend molecular diagnostics as a screening step to detect HPV DNA and additional testing as a triage step before treatment. These recommended methods often require patients to be referred or patient samples transferred to a different facility at the PHC level or higher, delaying treatment and causing loss to follow-up.

The opportunity in primary prevention is increasing access to the preventative HPV vaccines. Missed pre-cancer detection (secondary prevention) is currently a critical roadblock in preventing cervical cancer in LMICs. GH Labs has focused on developing new screening devices that are low-cost, easy to use by care providers, and readily accessible at the PHC level where patients first seek care: AVE, an AI-supported Automated Visual Evaluation device for enhanced visual assessment of the cervix, and NAATOS HPV, a nucleic acid amplification test (NAAT) with lateral flow technology on-a-strip (OS) for HPV detection at the PHC level (including multiplexing to simultaneously detect a greater number of HPV strains).

Countries Have Opportunities in Common to Improve Cervical Cancer Prevention

Cervical cancer screening has been opportunistically integrated into different health programs where women engage the health system in some countries. These include programs for HIV/AIDS, maternal health, and reproductive and sexual health, as well as family planning clinics. Such integration provides a more comprehensive service for women when they seek care, but it increases the workload for health workers. This burden can be mitigated by support for training plus infrastructure for integrated screening services, including diagnostic technologies that can support an effective and efficient combination of screening and treatment of cervical pre-cancer.

India

Taking India as an example, cervical cancer there is the leading cause of cancer mortality in women of reproductive age. India’s first indigenous HPV vaccine, produced by Serum Institute of India, is in the first stages of becoming part of the national immunization program, offering promise for primary prevention of cervical cancer. Screening, as secondary prevention of cervical cancer, is challenged by the availability of suitably trained female health care workers. As part of the expansion of health and wellness centers (2018), however, a new cadre of health worker, the Community Health Officer, has been added. This role holds responsibility for providing screening for cervical pre-cancer using the VIA method as well as other cancers and other non-communicable diseases, which could increase cervical cancer screening at the PHC level.