Cancer isn’t a single condition, but a name given to over 200 different forms of the disease.
The human body is built from cells. In a healthy body, these cells grow and divide in a controlled way, restoring any damage to our bodies.
Cancer begins when the cells within the body begin to change abnormally. Instead of dividing, cancer cells within the body continue to grow.
Abnormal cell growth can cause tumours to grow in the body. In cases of leukaemia, it can lead to the over-production of abnormal white blood cells which protect the body from infection.
If left untreated, cancer cells can sometimes spread, invading surrounding tissues – a process called metastasising.
In our lifetime, one in two of us will develop cancer.
Advances in cancer detection and treatment mean that cancer survival rates for all forms of the disease continue to improve.
How does cancer start?
How cancer develops
How cancer develops
Our bodies are made up of millions of cells. Within every cell is a nucleus which contains chromosomes that provide a home to thousands of genes. These genes ensure that the cells in our bodies grow and divide in a controlled way.
Cancer begins when genes become mutated or damaged, causing our cells to grow or divide uncontrollably.
Such mutations can happen by chance or be caused by the introduction of chemicals called carcinogens to the body. A person can also inherit faulty genes from their parents which can cause cancer.
In some cancers, these mutated cells continue to divide and grow in number, forming a lump, called a tumour.
Tumours can be non-cancerous (benign) or cancerous (malignant). As a malignant tumour grows, it begins to invade the surrounding tissues, causing damage.
The tumour secretes chemicals into the bloodstream. This stimulates blood vessels to grow around it, providing it with the blood it needs to grow.
At this point, cancer cells may detach from the tumour and spread to other parts of the body through the bloodstream or through the lymphatic system, a process called metastasising. This can sometimes result in a secondary tumour known as a metastatic tumour.
In blood-borne cancers such as leukaemia, lymphoma and myeloma, abnormal cells create too many white blood cells. This reduces the body’s ability to develop vital red blood cells and platelets.
Symptoms of cancer
Symptoms of cancer
Cancer has many symptoms. Spotting the signs of disease early is the best way of receiving an early diagnosis.
If you experience any of these symptoms, you must seek medical advice*.
- A lump that suddenly appears on your body.
- Unexplained bleeding.
- A change in toilet habits such as pain when urinating or blood in the urine or faeces.
Below is a list of some of the other common symptoms of cancer. Developing any of these symptoms does not mean that you have cancer, but you should see a doctor**.
- Unexplained, rapid or severe weight loss.
- Having a persistent cough or hoarse voice for several weeks.
- Bleeding or bruising with no known cause.
- Changes to the colour, shape or size of a mole.
- An ulcer or sore that doesn’t heal or get better.
- Blood in urine or faeces, even in small amounts.
- Difficulty passing urine.
- Pain or problems swallowing or eating.
- Excessive and unexplained night sweating.
- An unexplained pain that has lasted for longer than a few weeks.
- Night sweats or fever for no reason.
- Neurological problems, such as headaches, seizures, hearing changes or problems with vision.
Women should seek advice from a doctor if they experience any changes to their breasts or vaginal bleeding between periods or after the menopause.
If you notice any of these symptoms or experience any changes to your body that don’t feel natural, then speak to a clinician.