Explaining cancer words

This glossary, which includes definitions suitable for young children, teenagers and adults, may help you explain common cancer-related words.


 Word  To young children  To older children and teenagers
 Anaesthetic A medicine that makes someone go to sleep so they don’t feel anything when they have an operation. A drug that stops people feeling pain during a procedure such as surgery. A general anaesthetic puts someone to sleep. A local anaesthetic numbs one area of the body.
 Benign A bump or lump on the body that isn’t dangerous. Not cancer. Benign lumps or tumours do not spread to other parts of the body or become cancerous.
 Biopsy When the doctor looks at cells in the body to see if they’re healthy or not. A test to diagnose cancer. The doctor takes small bits of tissue from the body to look at under a microscope to see if the cells ahve changed.
 Blood count A test that checks how healthy the blood is. A test that counts the different types of blood cells in the body.
 Cancer Cancer is when bad cells – or trouble-maker cells – stop good cells from doing their job. The bad cells can grow into a lump or can cause problems in the blood. They can spread around the body too. Cancer is the name for more than 100 diseases in which abnormal cells grow out of control. This causes problems in the blood, or lumps – called tumours – to grow. Cancer can spread to other parts of the body.
 Cells The body is made up of billions of tiny things called cells, and each has a job to make your body work and stay healthy. Cells are the basic building blocks of the body. Our bodies constantly make new cells: to enable us to grow, to replace worn-out cells or to heal damaged cells after an injury.
 Chemotherapy Medicine that kills the bad cancer cells. Special drugs that kill cancer cells or slow their growth.
 CT scan A test that makes pictures for doctors to be able to see what’s happening inside someone’s body. A procedure that takes x-rays to get 3-D pictures of the inside of the body and show if cancer is present.
 Diagnosis When the doctor works out what is making someone sick. Working out what kind of disease or illness someone has.
 Immune system The part of the body that helps someone stay well by getting rid of germs inside the body. It fights illness if somebody does get sick. A network of cells and organs that helps protect the boyd from germs like bacteria and viruses, which can make people sick.
 Intravenous (IV) Putting a needle into a vein (where blood flows in the body). Something put into the vein, like a drip for feeding, or a needle to give medication or take out some blood.
 Malignant cells / Malignant tumour Another way of saying cancer. Cells or lumps that are bad. Cancer. Malignant cells can spread to other parts of the body.
 Medical oncologist A special doctor who uses strong medicine to treat people with cancer. A specialist doctor who treats cancer with chemotherapy.
(advanced cancer)
When the bad cells have travelled to another part of the body. When cancer has spread from one part of the body to another.
 Nausea Feeling sick in the tummy. Feeling as if you’re going to vomit. Nausea is a common side effect of chemotherapy.
 Palliative treatment When the doctors and nurses can’t stop the cancer from growing, but give the person medicine to make them feel better and stop the pain. Treatment that reduces or stops symptoms but doesn’t try to cure the cancer.
 Prognosis What the doctors think might happen to someone who is ill – i.e. how soon they will get better. What is likely to happen when someone has a disease, especially their chance of getting better and what might happen after treatment.
 Radiation oncologist A special doctor who treats people who have cancer using x-rays that beam into the body. A specialist doctor who prescribes radiotherapy and organises the treatment.
 Radiotherapy Invisible beams called x-rays that go into the body to kill cancer cells and make the cancer smaller. The use of radiation in the form of x-rays to kill or injure cancer cells so they can’t grow or multiply. This is different to when you get x-rayed to see inside you (e.g. for a broken leg).
 Recurrence/ relapse If cancer cells are left in the body, they can start to grow again, and the cancer comes back. When cancer comes back because of cancer cells that have not been affected by treatment.
 Remission When the cancer goes away after treatment. When cancer cells and symptoms disappear because of treatment. Remission doesn’t mean the cancer is cured, but it is now under control.
 Side effects Treatment can stop good cells from working, as well as bad cells. This can sometimes cause problems for the person with cancer, such as feeling tired, feeling sick or losing their hair. The unwanted effects of treatment such as nausea, hair loss, rash or fatigue from chemotherapy and/or radiotherapy. They occur because fast-growing healthy cells may also be destroyed by these treatments so they can’t do their usual work.
 Surgery This is when someone has an operation. A special doctor will cut out the cancer. An operation by a surgeon who removes the part of the body affected by cancer.
 Symptoms What people feel (e.g. sore, itchy) or see (e.g. redness, a lump) when things aren’t right in their body. Changes in the body caused by an illness, such as pain, tenderness, rash, stomach-ache etc. These help the doctor work out what is wrong.
 Tumour A lump in the body that shouldn’t be there. A lump in the body caused by uncontrolled growth of cells. Tumours can be benign (not dangerous) or malignant (cancer).
 Ultrasound A test that makes pictures of the inside of the body so the doctor can work out if anything is wrong. A scan that uses sound to create a picture of the body. It helps show where and how big a tumour is.
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