By Dr. Colin Michie
Dr. Colin Michie is a paediatrician specialised in nutrition, haematology and infectious diseases. He works as the Associate Academic Dean for the American University of the Caribbean Medical School in St. Maarten of which Bo Peng is a student.
Cancer of the Cervix: A battle that all women need to know about.
Cancer of the cervix may well be the most common malignancy that afflicts the women of St. Martin. It is frequent on neighbouring islands. This is a significant cancer and it can be tackled! Many women do not know about their personal risks of developing cervical cancer or the effective ways they can reduce their risks. In some parts of the world, the numbers of women troubled by this cancer have fallen dramatically because of national awareness campaigns. The cancer is caused by a long-term viral infection by Human Papillomavirus (HPV) of cells in the cervix and elsewhere. It takes many years for the infection to cause an invasive malignancy. There is therefore time to catch it early and eliminate it.
An international call to action!
Because it is possible to tackle cervical cancer effectively, the Director-General of WHO called last year for its elimination as a public health problem. There is a need for global action. Two steps are needed: First, vaccination against the papilloma viruses; second, to encourage all women to undertake cervical screening. A draft global strategy with goals and targets will be considered at the World Health Assembly in 2020. The combination of improved screening and vaccination will permit a dramatic reduction in this disease over the next 10 years.
Vaccination for all girls
Vaccines prevent against infection with high-risk papillomaviruses. Please ensure you receive a vaccine against papillomaviruses if you are under 26 years of age. On St. Martin, there are free vaccine programs on both sides of the island, started in 2013 and funded by PAHO to ensure that all teenage girls are offered these. Studies suggest that many eligible women do not receive this vaccination in the Caribbean or in developed countries. The vaccines began to be used in 2006; they are safe and are now on the WHO list of essential medicines.
In 2012, the use of vaccines in the USA had reduced infection with high risk papillomaviruses by one third in women in their early twenties. Globally, these vaccines could reduce cervical cancer deaths by two thirds. A report in the Lancet in the UK in late June showed that the vaccine is already reducing rates of genital warts dramatically. Boys will be vaccinated in many countries in the future in order to improve herd immunity and reduce the cancers caused by these viruses in women and men. No serious safety issues relating to the vaccine have been raised in these recent reviews.
Cervical screening for all women
Please ensure that you have cervical screening regularly from the age of 21 until 60 or 65 years. Screening should include a regular examination of your cervix every three to five years. This will allow a doctor to conduct a Papanicolou (PAP) test, which looks for early mucosal changes that could lead to cancer. A blood test to check if you have been infected with a papillomavirus is also useful. Thorough screening alone can reduce cervical cancer deaths by up to 80% in a community.
Other ways to reduce the risk of cervical cancer
Smoking tobacco is associated with higher rates of many cancers and lower rates of survival, including cancers of the cervix. This is a particularly powerful effect. Using condoms during sex reduces transmission of papillomaviruses and the risk of developing cervical cancer too. Having large numbers of sexual partners increases the risk of this illness: if you are in this group, regular cervical screening is particularly important. Finally, keeping your immune system healthy is crucial. Most of us fight and get rid of most papillomaviruses without knowing about it – our immune systems do this for us.
What you need to know about infections with papillomaviruses
Infections with human papillomaviruses (HPV) are common. There are at least 200 different types and approximately 40 types are transmitted by vaginal, anal or oral sex. From a global perspective, papillomaviruses are the most commonly transmitted sexual infection. Nearly everyone is infected with these viruses when they become sexually active. About half of these infections are with high risk papillomaviruses. The majority of infections with human papillomaviruses resolve over months to several years and do not cause complications. So it follows that most people suffer with an infection of a papillomavirus at some point in their lives and cancer is not the usual outcome.
The viruses find their way into the skin or soft tissues (mucosae) through microtraumas and infect stem cells in the basal layers of these tissues. Papillomaviruses can persist in these cells for many years and they spread when skin cells are shed from the area they infect. The papillomavirus is a hardy creature; many disinfectants do not kill it and it is difficult to remove from skin because of its habitat.
A small proportion of papillomavirus infections do not resolve or disappear. Over decades, these can cause warts and in some people, precancerous lesions. Some papillomaviruses such as HPV 1 and 2 cause warts or veruccae. Types 1, 2, 4 and 63 can cause plantar warts on the feet – these are not particularly infectious. Types 6 and 11 are the most common cause of warts in the genital area: these are more likely to spread between individuals and are more infectious.
About a dozen other HPV are regarded as high risk because they are linked to persistent infection that then causes different cancers of the genitals, cervix, anus, head and neck. These particular virus types make small proteins that act as oncogenes or accelerators for cancer change; they can also damage cellular DNA repair mechanisms. These are types 16, 18, 31 and 45. If one examines all the cases of cancer in the USA, high risk HPVs are associated with 3% of cancers in women and 2% of men. These figures are over 12% in Africa.
Most cancers of the mouth and pharynx are caused by papillomaviruses. These cancers are the most rapidly growing group among white men in the USA. Over 90% of anal cancers and 75% of vaginal and vulvar cancers are caused by papillomaviruses. Of the various types of papillomavirus, it is HPV 16 that is the most malignant: it is found in just over half of cervical cancers. When this virus causes a slow infection, lasting over 10 years, it can cause early pre-cancerous changes to cells lining the cervix.
Where do you catch HPV16? It is not possible to be infected by a toilet seat. The most common causes of infection are genital contact, or less frequently, spread from hands. It is for this reason that condoms are useful, but not completely protective: the virus can often be found on the skin of the upper legs and hands in most of those who are infected with it.
What happens if I develop cervical cancer?
There are a number of different treatments for patients with cervical cancer, depending on how far it has spread. Treatments include surgery, radiotherapy, chemotherapy, targeted treatments and immunological therapies. There are research trials of different therapies run from different hospitals, too, as some research groups are developing new and hopefully more effective approaches to treatments. All the treatments are more effective if the cancer is small, if it is found early and if the patient’s immune system is working well. A useful resource for possible treatment options is outlined at: (https://www.cancer.gov/types/cervical/patient/cervical-treatment-pdq#_180)
What is happening on St. Martin to help with these viruses?
Free vaccination is offered to all girls on the island – this is important for the future. Next, a network of laboratories, one of six across the globe, is dedicated to analysing biopsies collected from the skin or mucosae of patients from this island. Collaborations have established a registry of biopsies which are carefully analysed using international expertise to ensure the best treatment is delivered. We have good resources: let’s increase our knowledge to prevent and screen wisely to benefit our health and that of our children.
Maya Angelou, "Still I Rise"
“Just like moons and like suns,
With the certainty of tides,
Just like hopes springing high,
Still I'll rise.”
A team of authors contributed to this script:
Dr. C. Michie, Paediatrician, Associate Academic Dean, St. Martin.
Dr. L. Jeffry, Gynaecologist, Centre Hospitalier Louis-Constant Fleming, St Martin.
Dr. E. dos Santos, Medical Oncology, EC-DON Chair, British Virgin Islands.
Mr. L. Fusi, Gynaecologist, London Northwest Hospitals NHS Trust, UK.
Dr. D. Divaris, Pathologist, Medical Director, Integrated Department Pathology and Laboratory. Medicine GRH/SMGH, Ontario, Canada.