What is cancer?
We’ve all heard about cancer. Each and every one of us almost certainly knows someone who has had cancer or died from it. Cancer is in the news every day, be it because some celebrity was diagnosed with it or sadly died from it, or because there is a scientific prospect of yet another drug that might help cure cancer. Or more research telling us what causes cancer and why.
But what is cancer? The mere mention of the word conjures up the thought of a certain and painful death, or gruelling treatment with no guarantee of a cure. So people prefer not to think about it too much, understandably. But cancer is not one disease with the same treatment and the same outcome in every patient that is diagnosed. Today, doctors know that cancer can be classified into over 100 different types, based on the tissue or organ that is affected, what caused the tumour, and whether there is an inherited factor involved. And each type needs to be looked at and treated differently.
However, the root cause of any cancer is the accumulation of changes that happen in our cells every day as we get older. Remember, we all started out as a single cell, growing and multiplying to form the different parts of our bodies. Once that process is completed, the cycle of cell growth, multiplication, and cell death is what maintains our bodies, allows wounds to heal, hair to grow, and our bodies to function. But this process of cell growth, multiplication, and death that defines a cell’s lifecycle is not perfect. Mistakes happen during multiplication, all the time. Some of these mistakes actually help us, improve our performance, or allow us to adapt better to our environment and stay healthy. Some mistakes have no impact at all and we just carry on functioning the way we do.
And then there are those mistakes that do affect the smooth functioning of a cell’s lifecycle itself. Once there are simply too many mistakes in the make-up of the same cell, that’s when cancer is born. The carefully controlled process of growth, multiplication, and cell death no longer functions and a cell that would normally die or be destroyed naturally at the end of its lifespan suddenly starts growing and multiplying uncontrolled and begins to form a tumour. Or if this happens to a blood cell, abnormal blood cells that cannot maintain the regular function of blood begin to multiply and crowd out the normal blood cells. The tumour continues to grow and begins to affect the neighbouring tissue, or begins to metastasize (this means individual tumour cells detach from the tumour and begin to travel to another part of the body and start multiplying there as well to form additional tumours). Metastasis is actually what causes most deaths from cancer because the body is simply not able to cope with the damage inflicted to our organs by the sheer number of tumours.
However, for a cell to be affected by enough changes to cause cancer naturally many years have to go by, which is why traditionally, older people used to be and still are affected more by cancer. So, I hear you say, what about all the news of more and more people, especially women, being diagnosed with more aggressive cancers at a younger age? Or cancer rates rising in countries traditionally not affected by as many cancer cases, like India, compared to many Western countries, where cancer has been a public health crisis for many years. What has changed? What is making all these young people get aggressive cancers so early in their lives? Surely, the biology of our bodies would not have changed that much in such a short time span!
Well, it hasn’t. However, what we do to our bodies, what we eat or drink, or how we spend our days at work or at home, that has changed dramatically over the last decade. Especially so in India and many other emerging markets, as lifestyles are changing and emulating Western diets and work styles has become the norm.
What is so bad about those new lifestyles, those new habits we’ve readily embraced and sometimes even hanker for, like junk food, a holiday in the sun, or that drink after work with friends or alone at home to wind down from a stressful day at the office? Read more about this in part one of our blog series on What causes cancer?.