In this HealthSketch, we’re going to talk about cancer, a very common condition that
affects millions worldwide. Cancer can affect anyone, but risk generally increases with age.
Most of us have heard of it, but do you actually know what it is?
In fact, cancer is a group of over 100 diseases caused by uncontrolled cell growth.
Your body is made up of trillions of cells of different types. These cells are constantly
working, dying and being replaced through a process called cell division, where the cells
make copies of themselves. This process usually happens in a very controlled way, so that we
maintain the right numbers of each type of cell. This is because of the DNA: a code of instructions
which carefully controls what each cell does, telling them when to die or when to divide.
However, errors can occur in the DNA instructions, called mutations. DNA
mutations can occur randomly, when the cells don’t copy themselves correctly,
and these random errors build up over time, which is why cancer risk increases with age.
DNA mutations are also caused by environmental factors that damage DNA,
such as: tobacco smoke, alcohol, obesity, pollution, certain infections, and sun exposure.
More rarely, mutations are inherited or run in families. Mutations are often harmless,
but sometimes cause a cell to copy and grow uncontrollably, which is how a cancer starts.
These abnormal cells keep creating copies of themselves, growing into a clump or mass of cells,
called a tumour. Some tumours stay in one place and do not spread, known as benign
(or non-cancerous) tumours, and these are less likely to cause problems.
Tumours can also be malignant or cancerous, which means they can spread to other parts of the body.
Malignant tumours are more likely to cause problems, as they invade other body structures,
affect the way the body works, or use up the body’s nutrients. Tumours that have
spread away from the primary site of the cancer are called ‘metastases’, or ‘mets’.
Therefore it is really important to detect cancer at an early stage,
as it is easier to treat before it has had a chance to spread.
Routine screening tests are used to pick up some common cancers. It’s also important
to see a doctor if you experience unexplained symptoms that could be a warning sign of cancer.
Various investigations are used to diagnose cancer. These might include blood tests,
imaging tests, and a biopsy - where cells are taken for examination under a microscope.
If a tumour is found, these investigations help determine the type, size and spread of cancer,
which is called its stage. This is used to work out the most appropriate treatment.
The aim of cancer treatment is to remove or destroy the tumour cells in the body,
while minimising damage to normal healthy body cells. The main types of cancer treatment include:
Surgery: where the tumour is removed from the body.
Chemotherapy: where anti-cancer medicine is taken to kill off cancer cells.
Radiotherapy: where radiation is targeted to destroy cancer cells.
Other forms of cancer therapy include: immunotherapy, hormone therapy, and gene therapy.
Some cancer treatments also have an effect on normal body cells,
particularly fast-growing cells like the skin, hair, gut and bone marrow. This can
lead to a range of side effects, such as rashes, hair loss, nausea, and tiredness,
though these are generally temporary and usually resolve after treatment finishes.
Cancer treatment might significantly reduce the tumour size and ease symptoms,
known as ‘remission’. But it is often difficult to know whether all the cancer cells have been
removed or destroyed, and if some remain in the body, the cancer might return, months or years
later, which is called a ‘recurrence’. The overall prognosis varies a lot from person to person,
depending on the site, type and stage of cancer and the treatments available. Due to the
remarkable progress of medical science, advances in cancer therapy are happening all the time,
and these continue to lead to improvements in cancer survival worldwide.
We hope this HealthSketch has been helpful to you and those around you.
HealthSketch, health for all to see.