Dr. Colin Michie has worked as a paediatrician in the United Kingdom, Africa, the Caribbean and the Middle East. He has specialised in nutrition, haematology and infectious diseases. Now the Associate Academic Dean for American University of the Caribbean Medical School in St. Maarten, his enthusiasm is in teaching and training.
“I used to fancy crabmeat as a treat. Now Crab’s the epicure, and I’m the meat”. James Michie (2007)
Cancer is becoming more common a diagnosis as the world’s population becomes older and as other disorders such as heart disease, stroke and diabetes are treated more effectively. It is a sign of the success of our species, the advances made in science and medicine. There is another success story too; that of the increasing numbers of survivors of cancers. On a global scale we are getting better at treating them. This was signalled earlier this year by American Cancer Society as well as by CONCORD-3, a study run in 71 countries and territories.
The not-so-good news is that these figures are not the same in all countries. A website allows you to explore these data (http://globocan.iarc.fr/Default.aspx). The regional Pan American Health Organisation website is also really informative (https://www.paho.org/hq/index.php?option=com_content&view=article&id=292:cancer-program&Itemid=3904&lang=en). For instance, for women diagnosed with breast cancer in 2010-2014, the 5-year survival is 89.5% in Australia, 90.2% in the USA, but 66.1% in India. These figures can be used as a measure of quality of health care. They also show that cancers are not the same in different countries.
So much for the news. The main problem, though, is an old one. We are all (almost) terrified of a diagnosis of cancer. In the face of this natural terror, whether it involves us, our relatives or our friends, we must use the resource of knowledge. If we know more about these enemies, we will be less worried. Cancers can be found and treated. If found early, cancers are easier to treat and treatments are more likely to succeed. Left untreated, it is very unlikely they will go away. At present, figures from the USA show that 67% of those with a diagnosis of cancer are alive 5 years later. This is the first of several articles on different cancers, designed to explore how they behave and how they can be tackled.
What are cancers and how are they caused?
Cancers are collections of cells that cannot stop multiplying. Normal cells will divide 50 to 70 times then stop. However, cancer cells do not have these normal brakes: many of them keep dividing. For instance, HeLa cells from a patient who died in 1951 of cervical cancer are still used by scientists for research as they continue to multiply. Rogue cells form in our bodies regularly. Our immune systems are designed to destroy them. This is why we need to keep our immune systems as healthy as possible; they defend us against this common enemy and they are our most powerful shield or protection.
Cancers behave differently to the cells around them. A prostate cancer cell for instance will multiply to form a lump. As it becomes large, some of these cells will move into the blood vessels and spread, sometimes to the liver, the lungs or the bones. There they can form other lumps called secondaries or metastases. The immune system will stop or slow down metastases.
Why do cells become malignant? The most common reason is age: cancer is more common as we get older. It is seen more frequently in those with obesity, in those with damaged immune systems or long-term inflammation. This is why good diets become really important: we need to reduce inflammation and support our immune systems as best we can.
Substances such as tobacco and alcohol can increase the chances of developing many different types of cancer. Radiation, including ultraviolet rays from our St. Maarten sunlight can also cause changes in the genes that lead cancers to develop. A number of infections predispose to cancer. The most common of these are the papillomaviruses that cause cancer of the cervix, the head and neck; hepatitis viruses can cause liver cancer. A bacillus named Helicobacter pylori that lives in the stomach in some individuals can cause cancer of the stomach and oesophagus. About 5-10% of cancers develop because of mutated or damaged genes inherited from our parents.
The accelerators and brakes
Cancer promotors like these cause cancers by changing the way our genes work. Two main routes take cells on the road to become malignant. One involves cell growth genes which are like the accelerator in a car: the oncogenes control how quickly it divides. If oncogenes do not work together, cells can proliferate rapidly. A second set of controls are tumour suppression genes that usually slow cell division, instructing cells when to die or repair their DNA. About a half of cancers, when examined for their genes have abnormalities in these gene ‘braking’ systems. (Some cancers grow more slowly and are less likely to spread these may be referred to as benign.
Taking on the fight: which are the largest targets?
Of the lifestyle choices that will reduce most cancers, one stands out. Tobacco smoking accounts for between 25-30% of all cancer deaths in the USA. This habit is one that is really worth kicking because the toxins from cigarettes are likely to affect those living close to a smoker too. Cigarette smoke changes the way genes work in our head, neck, chest and bladder, so that even those already with cancer are going to have a better outcome with their treatment if they stop smoking. Less smoking will improve the health of lungs, hearts and arteries.
Which cancers can be prevented? The most common cancer among women in many Caribbean islands – cervical cancer – is caused by one of the human papilloma viruses. If you are under 26 years of age, a vaccine can protect you against this. Here in St. Maarten a process has been in place since 2013 to vaccinate girls in secondary schools, just as in many other countries. The benefits of this will take time to show, but public health officials are protecting our next generation with this useful strategy. In the meantime, cervical screening is really useful in preventing this malignancy.
Why is early detection important?
Increasing numbers of effective cancer treatments are available. As an outstanding example, in the 1960s acute leukaemia killed almost all the children it afflicted. Now, the survival to 5 years is over 90% with leukaemia’s. Lung cancer has a much higher survival rate too if found early, as have cancers of the cervix and breast. Our main cancer enemies in the Caribbean need to be found sooner.
Newer early treatments are now tailored. Depending on the age of the patient, the genes working in the cancer and depending on how far it has spread, different strategies are used. Surgery, drugs and radiotherapy can all be employed in combination to allow specialists to coordinate an attack on rogue cells. Treatments can slow down multiplying cells, encourage the immune system to work more effectively, and new imaging systems can allow these effects to be measured.
What should I do?
You are in charge of your health and your lifestyle. Avoid cancer risk factors. This is a big challenge as all of us have regular temptations with food, alcohol and tobacco.
Think regularly about your body. Know your body! You know it best! If you are worried, see a doctor for a check-up. Doctors can reassure you, or arrange screening or investigations. St. Martin has good facilities both on and off both sides of the island.
Talk about cancer to family, friends, those at work, those in the hairdresser or barbershop. Reducing fear is a very important part of fighting cancer. Our Positive Foundation on St. Maarten has been very valuable in supporting women with questions about breast cancer in particular.
A cancer survivor Susan Gubar adapted the words of Nina Simone’s “Mississippi Goddam” to shout out about the indignity and fierceness of cancer. Two stanzas are powerfully relevant. I hope she wouldn’t mind my citing them:
Lord have mercy on this land of mine
Will we all get it in due time?
People gone here,
People gone there,
I’ve even stopped believing in prayer.
Don’t tell me
I’ll tell you —
Me and my tribe are just about due.
I’ve been there so I submit
They keep on saying “Beat it!”