Cervical cancer is no longer the killer it once was in the U.S. since regular Pap smear screening was introduced in the 1950s. But according to the World Health Organization (WHO), cervical cancer remains the second most common cancer among women worldwide. In some developing countries, cervical cancer is the main cause of death of women of reproductive age.
Yet these deaths would be preventable with screening and treatment, and there are now new vaccines and DNA tests that experts are calling the biggest medical breakthrough of the 21st century. Dr. Jose Jeronimo, a gynecologic-oncologist and senior advisor for women’s cancers at PATH, an NGO focused on global health innovations, says: “I think this is a breakthrough. We dreamed about this 10 years ago.”
Discovery of HPV Leads to Breakthrough
For years, experts suspected that cervical cancer was caused by a sexually transmitted agent. It was only in the 1980s that scientists confirmed that it was caused by the Human Papillomavirus (HPV). HPV is so common that almost all sexually active men and women are exposed to it over their lifetimes. Not all 100 varieties of HPV cause cancer, but 13 are cancer causing and are referred to as “high-risk type.” Two of them, HPV types 16 and 18, cause 70 percent of cervical cancers and precancerous cervical lesions.
Once this discovery was made, as well as introducing better screening methods, scientists moved quickly to develop vaccines to immunize girls before being exposed to the virus. This vaccine has been hailed as one of the biggest modern medical breakthroughs. Australian researchers believe that they are on track to completely eradicating cervical cancer in their country. Dr Jeronimo notes that Latin America has been investing in addressing cervical cancer for over 20 years.
WHO recommends vaccination for girls aged 9 to 13 as this is the most cost-effective public health measure against cervical cancer. However, the vaccines cannot treat HPV infection or HPV-associated diseases, such as cancer. Women and girls who have been exposed to HPV over their lifetime still carry the risk of developing cervical cancer, which is why it will still take years for cervical cancer to be eradicated, even in affluent countries.
Challenges for Low-Income Countries
Despite this progress, an estimated 266,000 women die every year from cervical cancer, more than 85 percent of whom live in low-income countries, according to the International Agency for Research on Cancer. Access to healthcare is key. Screening for early detection allows treatment before cancer becomes invasive. Because precancerous lesions take many years to develop, the WHO recommends screening for every woman from aged 30 to 49 at least once in a lifetime and ideally more frequently.
Screening tests used to mean the conventional Pap smear and liquid-based cytology. However, those tests require laboratories with skilled technicians, a luxury not available to many women in the developing world. Another more user-friendly screening test is Visual Inspection with Acetic Acid (VIA), or the “Q-tip and vinegar” method. Health workers can, with a simple bottle of vinegar, a cotton swab, a vaginal speculum and a flashlight, travel to rural and remote areas to test women and provide results on the spot. Vinegar, when gently swabbed across the cervix, will make any abnormal cells appear whitish in color and indicate precancerous cells; patients can then be referred to medical clinics for early treatment, with precancerous cells being cut away or removed through freezing.
Hope in the Battle
New technology has also been developed that allows for the detection of HPV at earlier stages than the Pap smear. These new screening methods, based on molecular tests, are significantly more reliable. Along with the U.S and Europe, Mexico and Argentina are moving towards using this technology.
What’s more, these new tests can even be self-administered. In poorer countries where it can be difficult for women to reach clinics or where labs are unavailable, women can take their own sample of cervical cells. PATH has been partnering with health ministries in Central America to introduce a version of this self-administered DNA test in Guatemala, Honduras and Nicaragua.
Other organizations have deployed community health workers in order to educate girls and women on the HPV vaccine and to train medical center staff on how to screen for cervical cancer. In Haiti, cervical cancer is the most common cancer in women and the second leading cause of female cancer deaths. Last year, Partners In Health launched a two-year program aiming, in one geographic area, to vaccinate 20,000 girls against HPV and screen 20,000 women for cervical cancer by VIA. Partners in Health is also working with the Ministry of Health to make cervical cancer a national priority.
When cervical cancer is raised to this level of importance, dramatic changes can take place to improve the lives of women and girls. Bhutan and Rwanda are two such success stories. The WHO notes that, while vaccination programs have changed the landscape of global health drastically, there is usually a gap of 15 to 20 years between rich and poor countries in terms of the introduction of vaccines. The new HPV vaccines were introduced in 2006 in the U.S., U.K., Australia and Canada.
Cervical cancer was the most common cancer among women in Rwanda, but before 2011, neither screening nor HPV vaccinations were available in public health facilities. However, in 2010, the Rwandan government secured a partnership with Merck, one of two companies providing the new vaccines, to undertake a national “rollout” campaign, thus becoming the world’s first low-income country to provide universal access to HPV vaccinations. This was possible because the Rwandan government had already invested in 45,000 community health workers and disease prevention programs that reduced malaria incidence by 70 percent and under-five mortality by 50 percent. Nevertheless, the HPV vaccination rollout was a monumental undertaking that resulted in the Rwandan program attaining more than 93 percent coverage following the first three-dose course of vaccination.
The Road Ahead
National HPV vaccine rollouts can be subject to further complications because, unlike most other vaccines, which are administered to children under the age of five, HPV vaccines are given to adolescent girls before they become sexually active. Dr Seth Berkley, CEO of the GAVI Alliance says, “With limited access to screening and treatment, it is all the more important to vaccinate girls against HPV to give them the best protection possible against cervical cancer, which claims more than a quarter of a million women’s lives every year.”
International efforts, including those of the GAVI Alliance, to make the vaccines more affordable and thus more accessible have lowered the cost of vaccines to $4.50 per dose (they cost more than $100 in high-income countries).
Groups like PATH are also trying to find better solutions to treatment of precancerous lesions and invasive cervical cancer. For example, cryotherapy, an effective treatment to remove pre-cancerous cells, requires a refrigerant gas that can be complicated to procure and which is often too expensive for many women.
Meanwhile, there are known risk factors that contribute to the persistence of HPV and development of cervical cancer. These include sexual intercourse at young age, multiple sexual partners, tobacco use and suppressed immune systems. In addition to education, screening and access to vaccines, reducing HPV infection and cervical cancer in developing countries ultimately requires the removal of barriers that prevent women and girls from accessing healthcare.
Asked about the biggest challenge faced in tackling cervical cancer, Dr Jeronimo says: “Political will is needed, the decision for investment and support, not only by the countries but also the organizations dealing with health there – the donors, the international agencies, NGOs. They have to understand that there are opportunities now. That’s also an important role for the media to get that message out there.”