How to Prepare for a Bone Scan

If your doctor thinks cancer may have spread to your bones, a test called a bone scan can help them learn more.

What is a bone scan?

A bone scan is one type of imaging (radiology) test called a nuclear medicine scan. It’s a special test that uses a small amount of radioactive material to check for signs of bone problems. The radioactive tracer travels through the bloodstream and is attracted to bony areas that have lots of cell activity, including where bone is growing, healing, or has abnormal cells. These areas “light up” on the scan to show doctors where problem areas might be.

Bone scans have many uses. They can help identify a bone infection or fractures and other bone injuries that might not show up on x-rays. For people with cancer, a bone scan is one of the nuclear medicine scans most commonly used to look for signs of cancer. While it cannot diagnose cancer, a bone scan can often find bone changes much earlier than regular x-rays.

The amount of radiation used in a bone scan is about the same as what you’d get from a regular x-ray. Although a bone scan takes several hours from start to finish, the procedure is normally straightforward and not painful.

Why doctors order bone scans

When a patient is first diagnosed with cancer, a bone scan may be used to help determine the cancer stage. Bone scans are also routinely done for certain types of cancer to help doctors know if the cancer has spread, or metastasized, to the bones. This means that bone scans may be used as part of a patient’s ongoing and follow-up testing to monitor for possible bone metastasis.

“Some patients with certain types of cancers will get bone scans periodically. Some patients may never get a bone scan or they may get another type of test, like a PET scan. It depends on the type of cancer,” said Vicki Keedy, MD, MSc, an American Society of Clinical Oncology (ASCO) expert and a medical oncologist at Vanderbilt Ingram Cancer Center.

Certain types of cancer, including prostate, breast, ovarian, kidney, and lung cancers, are more likely to spread to the bone than others.

How to prepare for your bone scan appointment

As you get ready to go to your bone scan appointment:

• Wear comfortable clothes.
• Remove any jewelry or metal.
• You can eat and drink as usual.
• You may be restricted from taking certain medications. Ask your doctor in advance.
• Pack a bag with things, like a book or word puzzles, to help pass the time in the waiting room. Or you can download a movie or game to your phone to keep you occupied.

What to expect before your bone scan takes place

Before a bone scan, patients receive an injection of a radioactive tracer called technetium. The injection is given through a vein in your arm, or intravenously (IV). The tracer emits a special type of light that the scanner machine can detect. After getting the tracer injection, you’ll have some waiting time as the tracer makes its way through the bloodstream to reach your bones.

“This waiting period can take 2 to 4 hours, depending on the facility’s bone scan procedures and where you get your test done. You’re not in the scanner during this time. You are in the waiting room. During most of the time it takes to complete a bone scan, you’re just waiting,” Dr. Keedy said.

What to expect during a bone scan

Similar to a CT scan table, the bone scanner table that you lie on is narrow. You do not go through a tube like in an MRI, but you do have to stay still for about 30 to 60 minutes during the actual scan. A special camera slowly moves above you to take pictures. The result will show any areas of concern.

What happens during the actual bone scan:

• You will lie on a narrow table.
• Cameras will come close to you, but they won’t touch you.
• You should stay as still as possible.
• The scanner may move up and down or around in circles.

What happens after a bone scan

Staying hydrated to help eliminate the tracer from your body is important. “You’ll want to drink plenty of water after a bone scan to flush the radioactive tracer. If you’re breastfeeding, you should discard the breast milk for a certain amount of time after that procedure. There is no risk of radiation exposure to those around you, and there are typically no lasting side effects,” Dr. Keedy said.

After your bone scan:

• The tracer leaves your body through the urine and is usually gone within about 48 hours.
• You should receive test results within 2 to 3 days. It’s best to review the results of a bone scan with your doctor to better understand what you’re seeing.
• If the bone scan shows anything abnormal, more testing may be needed, such as an MRI or a biopsy.

Questions to ask your doctor about bone scans

Dr. Keedy suggests several questions to ask your doctor before a bone scan, including:

• Why do I need a bone scan?
• What are you looking for?
• How and when will I know the results of the scan?
• How will you use the results of the scan?
• If you see cancer in my bones, what does that mean? Does it change my treatment options?
• How do I prepare for a bone scan?
• Can I drive to it?
• Can I eat before the scan and while I’m waiting after the injection?

“If the cancer has spread to the bone, that usually means a stage IV (4) cancer. For metastatic disease, it could potentially change a patient’s treatment goal and the type of treatments that are offered may differ,” Dr. Keedy said.

Knowing what to expect from a bone scan can help make the process smoother. If you have further questions or concerns about this procedure, reach out to your care team.

Dr. Keedy is a member of ASCO’s Patient Information Editorial Board.