Why Are Bone Scans Used for Prostate Cancer?

Prostate cancer may be common, but not all prostate cancers are the same. If you’re living with prostate cancer, you might have noticed that over time your treatment course is becoming different from others in your support network. While you all might have shared the same initial experiences — like prostate biopsies and ultrasounds — things can start to diverge as you get further into your treatment. 

Not everyone with prostate cancer gets a bone scan, so it can be hard to know where to turn for help. While your healthcare team can tell you what your bone scan means and why it’s important, you might have questions about what to expect and how to prepare. Here’s everything you need to know about getting a bone scan for prostate cancer. 

What is a bone scan?  

A bone scan is a special type of imaging study. It’s also called a “bone scintigraphy” or “technetium-99m-MDP scan.”

During a bone scan, you get a small amount of radioactive material called a “radionucleotide” (or tracer). The material sticks to certain parts of the bone more than others — this is called “uptake.” Once it sticks to the bones, the material gives off energy called “gamma rays.” The radiologist then uses a special camera, called a “gamma camera,” to take pictures of your entire body. The images will show if any of your bones have the tracer stuck to them. 

Although a bone scan uses radioactive material, it’s actually very safe. You’re only allowed to take a very small amount of this material, and you won’t have multiple scans or multiple exposures in a short time. Your body is able to get rid of the material safely once the procedure is over. 

Bone scans are very helpful in diagnosing and treating prostate cancer. They are a tool that let’s healthcare providers completely evaluate your bones. X-rays and other imaging studies may not be as precise. 

When do you need a bone scan for prostate cancer?

Bone scans are used to see if the prostate cancer has moved from the prostate and into the bones. This is called “bone metastasis.” 

If you have symptoms of bone metastasis, your healthcare team will ask you to get a bone scan. 

These symptoms can include:

• Bone pain 

• Unexplained broken bones

• Weakness or numbness in the legs 

• Loss of control of urine or stool 

• High levels of calcium in the blood 

Other reasons you might need a bone scan is if you are diagnosed with high risk or intermediate risk prostate cancer or if your PSA level is rising — especially after prostate removal. Depending on what type of treatment you had, a rising PSA level could mean that the cancer has moved to your bones. A bone scan might show signs of metastasis sooner than other images like MRI or CT scan. 

Not all prostate cancers are the same. Some types are more likely to move to the bones than others. If you have prostate cancer that is high risk for bone metastasis, your healthcare team might use bone scans to check how your cancer is doing during treatment. 

What should you expect during a bone scan?

A bone scan is painless, and there’s not much preparation required. Here are two things your provider might ask of you:

1. Don’t take any medications that have bismuth — like Pepto-Bismol — for about a week before your bone scan. These medications can interfere with the bone scan results. 

2. Try not to drink too many fluids the day of your test. During the test, you’ll be asked to drink a lot of water. Some people find it easier to do this if they haven’t had too many fluids before the appointment.

The day of your bone scan, be ready to spend several hours at the imaging center. A bone scan takes several hours to complete. You should bring something to help you pass the time, like a book or something to watch. Most people don’t need sedation medications for their bone scan, so you’ll be able to drive yourself home afterward. 

Here’s what you should expect during your bone scan:

• You’ll check in and your team will ask some basic questions. Let them know about any medications you take and if you have any allergies. 

• A healthcare provider will insert an intravenous (IV) line — usually in your arm. 

• You’ll be given the tracer through the IV. You might feel some coolness as the tracer moves into your arm — this is normal. Some people have mild pain and redness of their skin where the tracer is injected. This usually goes away within a few hours. Allergic reactions to the tracer are very uncommon. 

• After you get the tracer, you might have to wait about 3 to 4 hours for your bones to absorb the tracer. During this time, you’ll need to drink several glasses of water. This will help your body get rid of any extra tracer that your bones don’t absorb. While you’re waiting, you’ll be allowed to walk around and eat. Just stay nearby so the staff can check in with you. 

• After the waiting period, you’ll change into a gown and take off metal or jewelry that could interfere with the bone scan. You’ll be asked to empty your bladder one last time before the bone scan starts. 

• Then you’ll lie on the exam table and the gamma camera will take pictures. This can take between 30 and 60 minutes. You’ll be asked to stay still while the camera is taking pictures. You won’t feel any pain during this time. But if you have bone pain, you might be uncomfortable lying still on the table. Let your healthcare team know if you’re having pain when lying on your back. They can prescribe medication to keep you comfortable during the bone scan. 

• During the bone scan, you’ll be in an enclosed space. If enclosed or tight spaces make you anxious, let your healthcare team know before your exam. They can order medication to make you more comfortable during the exam. 

Once all the pictures are done, you can go home. The tracer in your bones will naturally leave your body through your stool and urine over the next day or so. You don’t need to do anything special to get the tracer out of your body. Drink a normal amount of fluids, and your body will do the rest. The amount of tracer you got was very small — you aren’t a danger to anyone who comes in contact with you. You don’t need to isolate or stay away from friends or loved ones. 

What happens after a bone scan?

A radiologist, usually one who is trained in nuclear medicine, will review your scan and make a report. The radiologist will look to see if there is tracer uptake in your bones — this could be due to many things, including:

• Prostate cancer metastasis

• Bone injury from your cancer treatment

• Other medical conditions

If there is tracer uptake on your scan, your healthcare team will work with you to decide the next steps in your treatment. Sometimes, a different type of scan — like a CT or MRI — is needed to get a more detailed look at a particular area. Or you may need a bone biopsy, a procedure where a small sample of bone is taken to look at under the microscope. Because every case is different, you’ll need to meet with your healthcare team to decide your next steps.

Why trust our experts?

Written by:

Christine Giordano, MD

Christine Giordano, MD, is board-certified in general internal medicine. She received her medical degree from Rutgers New Jersey Medical School and completed residency at Thomas Jefferson University.

Edited by:

Patricia Pinto-Garcia, MD, MPH

Patricia Pinto-Garcia, MD, MPH, is a medical editor at GoodRx. She is a licensed, board-certified pediatrician with more than a decade of experience in academic medicine.

Reviewed by:

Brandon R. Mancini, MD, MBA, FACRO

Brandon R. Mancini, MD, MBA, FACRO, serves as medical director at BAMF Health in Grand Rapids, Michigan in the emerging field of theranostics. His primary clinical focus is on the treatment of people with metastatic prostate and neuroendocrine cancers.

Our editorial standards

Meet our experts