Did you say cancer? Eliminated?
Writer: Jasmine Lai
Editor: Maria Stoica
Artist: Zach Ng
Personified as ‘the emperor of all maladies’, cancer is a process of mutation and evolution, making it the disease that is most intimate to human history and life, unrivalled by any other. With estimates that one out of every two people will receive a cancer diagnosis in their lifetime, the possibility of eliminating a type of cancer sounds almost unthinkable.
Just a year ago, the World Health Organization (WHO) launched a global strategy to accelerate the elimination of cervical cancer as a public health problem by 2030. This ambitious target hopes to achieve ‘90% of girls fully vaccinated by 15 years of age; 70% of women screened using a high-performance test by age 35, and again by age 45; and 90% of women identified with preinvasive and invasive cervical cancer properly managed’.
Whereas many common types of cancer are closely tied to our recent urbanised lifestyle choices, human papillomaviruses (HPV) have been in existence for millions of years and are responsible for almost all cases of cervical cancer. Yet not many other cancer interventions have made an impact as dramatic as the cervical cancer intervention as it takes a life course approach. Primary prevention begins in young girls (and gradually in boys too) through education and the three-dose HPV vaccination. Secondary prevention of cervical screening is through Pap smears, HPV testing or Pap/HPV cotesting, and tertiary treatment sees the typical range of surgery, chemotherapy, radiotherapy and palliative care.
But how did we get here?
In 1941, Georgios Papanikolaou published his work on the Pap smear 10 years after recognising its role in detecting cervical carcinogenesis. The Pap smear marked the first form of widespread cancer screening, but was only the second runner-up for a Nobel Prize. These cervical smears allowed for the identification of koilocytes and gradually led to identifying the cytopathic effect of an HPV infection and linking it to a causal agent. However, as this was against the central dogma of the time, after exhausting resources and finding little evidence, the scientific community had shifted its attention away from viruses and to environmental and genetic agents.
While some researchers focused on the herpes simplex virus, Harald zur Hausen pursued HPV based on anecdotes of genital warts becoming malignant carcinomas, despite initial scepticism and disregard. Hausen successfully demonstrated the presence of HPV DNA in cervical cancer cells in the early 1980s, winning him the 2008 Nobel Prize in Physiology or Medicine. Fast forward to 2006, Gardasil, the first HPV vaccine was approved, providing the tool we know to be most effective in eliminating disease. By covering the two strains that cause 70% of cervical cancer cases and two additional strains that cause 90% of genital warts, not only was direct prevention achieved, but herd immunity effects have also been observed through vaccination of both males and females.
Yet the history of HPV and cervical cancer is also a history of social, ethical and gender issues. Hausen found the cancerous HPV-18 strain from the immortalised HeLa cell line that was taken from Henrietta Lacks without consent. The vaginal speculum currently used in pelvic exams and pap smears was initially revived by male doctors to check prostitutes for venereal disease, and was not permitted for midwives to use despite their being responsible for medical intervention in women’s reproductive problems. And prevention itself has impediments. The stigma of HPV being a sexually transmitted disease, the taboo topic of the vagina and common harmless HPV infections are just a few of a whole host of factors that inflict psychological impacts and uncertainty on individuals on top of a potential cancer diagnosis.
In just eight years since implementing the vaccine, Scotland has reached near elimination of cervical cancer. But no party can be left behind as the burden of disease now resides in low- to middle-income countries. Global access to infrastructure, health education, vaccination, screening and primary healthcare have the potential to either alleviate or exacerbate inequalities. Interestingly, the measures put in place for COVID-19 vaccinations may provide an opportunity to improve HPV vaccination access.
For now, let’s take a moment to appreciate how far we have come since the beginning of cancer treatment and prevention: in scientific advancement, medical technology, united intervention strategies and public understanding.
And get vaccinated!
Well done Jasmine!