This scan looks at all the bones in the body. It is more sensitive than an x-ray, and it shows up any abnormal areas of bone more clearly.
A small amount of a radioactive substance is injected into a vein in your hand or arm. Abnormal bone absorbs more radioactivity than normal bone, so these areas are highlighted and picked up by the scanner. The abnormal areas are sometimes called "hot spots".
The level of radioactivity used in the scan is very small and doesn’t cause any harm to your body.
You will need to wait for 2 to 3 hours between having this injection and the scan. You may want to take a magazine, book or MP3 player.
If hot spots do show up on a bone scan, it is not always clear whether they are caused by cancer or by other conditions, such as arthritis.
Sometimes a CT scan or MRI scan may help the doctors decide whether the changes seen on a bone scan are caused by bone cancer or by another condition.
Some centres may do an MRI scan of the whole skeleton instead of a bone scan. This is to check for signs of cancer in any other bones away from the main tumour.