Cancer is a disease caused by normal cells changing so that they grow in an uncontrolled way. The uncontrolled growth causes a lump called a tumour to form. If not treated, the tumour can cause problems in one or more of the following ways
Your body is made up of billions of tiny cells that can only be seen under a microscope. These cells are grouped together to make up the tissues and organs of our bodies. They are a bit like building blocks.
Diagram showing how normal cells make up the tissue in our bodyDifferent types of body tissues are made up of different types of body cells. For example, there are bone cells in bone and breast cells in the breast.
Cancer cells are different to normal cells in several ways. They don't die if they move to another part of the body and
Tumours (lumps) can be benign or malignant. Benign means it is not cancer. Benign tumours
Benign tumours are made up of cells that are quite similar to normal cells. They will only cause a problem if they
Malignant tumours are made up of cancer cells. They
The diagram below shows a tumour appearing in cells lining a body structure such as the bowel wall. The tumour grows through the layer holding the cells in place (the basement membrane) and spreads into the bloodstream.
Diagram showing a malignant tumourIt is the ability to spread that makes a cancer harmful. If a cancer is not treated, it can spread into the organs near to where it started growing. It can also damage other parts of the body that it spreads to.
The place where a cancer begins is called the primary cancer. Cancers may also spread into nearby body tissues. For example, lung cancer can spread to the lining of the chest (the pleura). Ovarian cancer can spread to the lining of the abdomen (the peritoneum). This is called locally advanced cancer.
Cancer cells can break away from the primary tumour and be carried in the blood or lymphatic system to other parts of the body. There they can start to grow into new tumours. Tumours from cancers that have spread are called secondary cancers or metastases (pronounced met-as-tah-seez). A cancer that has spread has metastasised.
The diagram shows a primary bowel cancer that has spread to the liver.
The various organs of the body are made up of different types of cells. Any of these cell types can grow into a primary cancer. Different types of cancer behave very differently. The type of cancer affects whether it is
This section is about some of the tests you may have when doctors are diagnosing or treating your cancer. You may also have these tests as part of your routine follow up once your treatment is over. There is information about more specific tests in the sections about the different types of cancer.
Tablets or capsules - Injection or a drip into your vein - Central lines - PICC lines - Portacaths - Injection into your muscle - Injection under your skin - Syringe drivers - Suppositories - Stick on skin patches - Tablets you dissolve on or under your tongue - Treatment cycles
Radiofrequency ablation (RFA) - Laser treatment - High frequency focused ultrasound (HIFU) - Photodynamic therapy (PDT) - Cryotherapy - Ultraviolet light treatment
The following symptoms can be caused by cancer, but they can also be caused by many less serious illnesses. There is information below about
many symptoms can just as easily be symptoms of other illnesses or conditions that are much more common, and often less serious, than cancer. Be aware of what is normal for your body and look out for any changes. If you have a symptom that worries you or that is unusual for you, go to your GP for a check up.
