A bone scan cannot diagnose prostate cancer. But as prostate cancer advances, it can spread (or metastasize) to nearby bones. A bone scan can help identify when this has happened.

Prostate cancer happens when cancerous cells grow in the prostate, a gland located near the bladder that helps store and produce semen.

A bone scan can help determine how far the cancer has spread to the bones, such as the pelvis and spine.

Read on to learn more about how a bone scan can help determine whether prostate cancer has spread, who should get a bone scan for prostate cancer, and what scan results might mean for your next steps.

A bone scan uses a safe radioactive substance called a tracer. The tracer gets absorbed by your bones and emits gamma rays.

A gamma camera can detect where the tracer in your bones is emitting gamma rays and find areas affected by the growth of cancerous tissue. Unlike X-rays, bone scans can show detailed images of where cancer cells might be damaging healthy tissue.

The most common bone scans for prostate cancer are PET scans and bone scintigraphy.

Bone scan results can show accurate, detailed tracer interactions with your bones and other organs that might be affected by metastasized prostate cancer.

A bone scan can be used to find metastasized cancer if you’ve received a diagnosis of advanced prostate cancer.

Metastasized cancer cells can replace healthy cells and cause organs throughout your body to fail, so diagnosing and treating cancer that’s spread may be critical to your treatment plan.

A doctor may also suggest a bone scan if they suspect that cancerous cells have spread, even if the cancer is in the early stages. This can happen if your prostate-specific antigen (PSA) levels are high or if you have symptoms like:

Here’s what to expect when you get a bone scan for prostate cancer:

  1. You’ll receive a tracer through an intravenous (IV) line in your arm. You may feel a cold sensation as the tracer works its way through your body. But these sensations usually go away in a few hours.
  2. You’ll wait up to 4 hours for the tracer to fully absorb into your bones so that medical professionals can get the best possible results. You may need to drink a few glasses of water to get rid of extra tracer material in your body.
  3. You’ll change into a gown, remove jewelry, and urinate to empty your bladder.
  4. You’ll be asked to lie down on a table within a small, enclosed space.
  5. A scan technician will use a device called a gamma camera to take pictures of your bones near your prostate and any other areas a healthcare professional believes may be affected by cancerous tissue. You shouldn’t feel any pain during this process.
  6. When the scan is done, you can get up and change back into your clothes. You’ll usually be able to go home shortly afterward.

A doctor or radiologist will be looking for tracer uptake on your bone scan results.

Tracer uptake indicates that cancer has metastasized in your bones or that your bones are injured from cancerous cells or cancer treatment.

If there’s no tracer uptake, it’s likely that cancer hasn’t spread to your bones.

Depending on your results, a doctor might recommend a follow-up test to look at specific areas more closely. Tests include:

Here are some of the most frequently asked questions about prostate cancer testing.

What is the most accurate test for prostate cancer?

Prostate cancer is usually diagnosed using a combination of tests:

  • PSA tests check PSA levels in your blood. High levels can be an early sign of prostate cancer.
  • A healthcare professional may perform a digital rectal exam to feel around the prostate gland for any growths or atypical structures.
  • A prostate biopsy allows healthcare professionals to check a sample of tissue from the prostate for the presence of cancerous cells.
  • Imaging tests like a CT scan or MRI give detailed views of the prostate and the surrounding tissues. Doctors can use these scans to check how much cancerous tumors have grown.

What stage is prostate cancer when it spreads to the bones?

Prostate cancer that spreads to bones is categorized as stage 4, the most advanced form of prostate cancer.

Prostate cancer can still be treated at this stage. But destroying or removing cancerous cells becomes more difficult as it spreads further into surrounding bones and tissues.

How long does a bone scan take for prostate cancer?

On average, a full-body bone scan can take between 1 and 4 hours. This includes the time it takes for a tracer to get into your body and be fully absorbed by your bones.

A bone scan cannot diagnose prostate cancer, but it can detect how far it may have spread.