A whole-body bone scan is a nuclear medicine test: a very small amount of radioactive material is injected into a vein and collects in the parts of the bones that are repairing or changing; a special camera then takes pictures of the whole skeleton [1, 2]. In cancer, it is mostly used to see whether cancers such as prostate, breast, lung or kidney cancer have reached the bones; but it also shows hidden fractures, bone infection and arthritis [1]. Not every "hot spot" on a scan is cancer, and another test such as an X-ray, CT scan or MRI is often needed; in high-risk prostate cancer, a PSMA PET scan is more accurate [1, 4].
Key points
- A bone scan shows changes in bone very early, sometimes weeks or months before a plain X-ray, and looks at the whole skeleton in one test [1].
- The radiation dose is low: about the same as the radiation everyone receives from nature in about a year [1, 8]. No special measures are needed for your family [1].
- Not every dark spot (hot spot) is cancer; arthritis, old or new fractures and infection can look the same [1].
- In low-risk prostate cancer and in early-stage breast cancer without symptoms, a bone scan is usually not needed [3, 5].
- In high-risk prostate cancer, a PSMA PET scan is more accurate than a CT scan plus a bone scan, and gives less radiation [3, 4].
What is a bone scan and how does it work?
A bone scan (bone scintigraphy) is a test done in the nuclear medicine department. A very small amount of radioactive material (usually attached to a medicine similar to bone drugs) is injected into a vein in your arm and travels in the blood to the bones [1, 2]. It collects mostly where blood flow and bone remodelling are higher, that is, where bone is repairing or changing because of cancer, a fracture, infection or wear and tear [1]. A few hours later, a special camera takes pictures of the whole skeleton [1].
The advantage of a bone scan is that it shows all the bones of the body at once with a relatively low radiation dose and finds changes earlier than a plain X-ray [1]. Its drawback is that it does not tell you what has caused a dark spot; this is why three-dimensional pictures on the same day (SPECT or SPECT/CT) or another test are sometimes needed [1].
What is a whole-body bone scan used for? Bone scans in cancer and other conditions
Checking whether cancer has spread to bone
In cancers that often spread to bone, such as prostate, breast, lung and kidney cancer [1]. Read more: Bone metastases
Unexplained bone pain
Before treatment with radioactive bone medicines
Before treatments that deliver radioactive material directly to the affected parts of the bone, such as radium-223 [1].
Conditions other than cancer
Hidden or stress fractures, bone infection, arthritis and joint inflammation, Paget's disease and loosening of a joint replacement [1].
In prostate cancer and breast cancer, who needs a bone scan?
Prostate cancer. Your doctor works out your risk group from the PSA, the Gleason score and the size of the tumour [3]. In low-risk and favourable intermediate-risk cancer, the European guideline does not consider further imaging to look for spread necessary [3]. In unfavourable intermediate-risk and high-risk cancer, a check for spread is recommended: a PSMA PET scan if available, otherwise at least a CT scan (or MRI) of the abdomen and pelvis together with a bone scan [3]. If you have bone pain, a scan is needed however low the PSA is [2, 3]. See your risk group with the prostate cancer risk group tool and read about the Gleason score.
Breast cancer. In ductal carcinoma in situ (DCIS) and in stage 1 and 2 cancer without symptoms, which have a low risk of spread, routine bone scans, CT scans or PET scans have not been shown to help and can lead to further unnecessary tests [5]. If you have new bone pain that does not go away, tell your doctor [1]. Read more: Breast cancer
Read about which tests are needed after treatment ends: After cancer treatment ends.
How to prepare for a bone scan, and what happens on the day
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A few hours of waiting
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How much radiation does a bone scan give? Is it safe for family and children?
The radiation dose of a bone scan in adults is about 3 to 4 millisieverts [1]; roughly the same as the radiation everyone receives from natural sources in about a year (about 3 millisieverts), and less than a CT scan of the abdomen and pelvis (about 6 millisieverts) [8]. If a CT scan is done on the same day, its radiation is added separately [1]. Read more: Do CT scans and X-rays cause cancer?
- Family: according to the European Association of Nuclear Medicine guideline, no special measures are needed for the patient's family [1]. If your centre gives different advice, follow it.
- Anyone caring for the patient: for the first 24 hours, wear disposable gloves for tasks such as cleaning up urine or changing adult pads [1].
- Breastfeeding: to be on the safe side, stop breastfeeding for at least 4 hours and throw away one feed of expressed milk [1].
- Pregnancy: the test is usually put off until after pregnancy, or an ultrasound or MRI is chosen instead [1].
Bone scan results: what does a hot spot or increased uptake mean?
On a bone scan report, the places where more radioactive material has collected are called "increased uptake" or "hot spots" [1]. This means the bone is more active at that spot, not necessarily that there is cancer. A bone scan is very good at finding changes, but not good at telling what has caused them; this is why an X-ray, CT scan, MRI or PET scan is often needed [1].
| Term on the report | What it usually means | Next step |
|---|---|---|
| Normal bone scan | No sign of active change in the bones was seen [1] | As your doctor plans; a normal scan does not rule out every very small or purely destructive lesion [1, 4] |
| Degenerative changes | Wear and tear and arthritis of the joints or spine [1] | Your doctor compares it with your symptoms, examination and other imaging [1] |
| Focal increased uptake (in one or more spots) | This can be cancer spread, an old or new fracture, infection or Paget's disease [1] | A three-dimensional picture, plain X-ray, CT scan or MRI of that area [1] |
| Multiple lesions suggestive of metastases | Several spots whose shape and pattern look most like cancer that has spread to bone [1] | Your doctor weighs the result against the PSA or other tests, sometimes a biopsy, and plans treatment [1, 3] |
| Photopenic or cold lesion (reduced uptake) | Sometimes seen in lesions that only destroy bone without forming new bone [1] | Usually another test, such as a PET scan or MRI [1] |
Only your own doctor, looking at all your other test results, can tell you exactly what your report means.
Looking worse after treatment starts. If the scan is repeated less than 6 months after treatment begins, darker or more spots may mean the disease has progressed, but sometimes they are a "flare": the bone is healing and the treatment is working [1]. To decide, your doctor compares the result with the PSA, your symptoms and other tests.
Bone scan or PSMA PET scan for prostate cancer? How it compares with MRI and other PET scans
| Test | What it shows best | Where it is mostly used |
|---|---|---|
| Bone scan | Active changes throughout the skeleton, especially lesions that form new bone [1] | Checking for spread to bone when a PSMA PET scan is not available, bone pain, hidden fractures [1, 3] |
| PSMA PET scan | Prostate cancer cells in lymph nodes, bone and elsewhere; more accurate than CT and bone scans [3, 4] | High-risk or unfavourable intermediate-risk prostate cancer [3] |
| MRI | Shows the spine in detail and finds spread to the vertebrae better than a standard (two-dimensional) bone scan [1] | Back pain or suspected pressure on the spinal cord; sometimes whole-body MRI [3, 7] |
| FDG PET scan | Lesions that destroy bone are seen better than on a bone scan [1] | Cancers that mostly cause destructive bone lesions, such as lymphoma [1] |
| Fluoride (NaF) PET scan | In one study it was slightly more accurate than a three-dimensional bone scan [6] | High-risk prostate and breast cancer, in centres that have it [6] |
In a large study of men with high-risk prostate cancer, a PSMA PET scan showed cancer spread much more accurately than a CT scan plus a bone scan, gave fewer unclear results, led to changes in the treatment plan more often, and gave less than half the radiation [4]. This is why the European guideline prefers a PSMA PET scan for these patients, if available [3]. But the bone scan is still a sensitive test, and the European guideline bases its treatment recommendations on it, together with CT or MRI [3]. Read more: What is a PET scan and how is it used in cancer? and How is cancer diagnosed?
When should I call my doctor?
If you have or have had cancer, contact your doctor or care team within 24 hours if you have [7]:
- severe back pain that does not go away, or pain that gets worse day by day [7]
- pain that is worse when standing, sitting, moving, coughing, sneezing or straining, or that disturbs your sleep at night [7]
Go to an emergency department straight away or call your local emergency number if, along with back pain, you have any of these symptoms; the cancer may be pressing on the spinal cord [7]:
- weakness or heaviness in the legs, difficulty walking or falls
- numbness, tingling or loss of feeling in the legs, or pain shooting down the legs
- loss of bladder or bowel control
Frequently asked questions
How long does a bone scan take?
Is a bone scan painful?
You only feel the needle of the injection. While the pictures are taken you need to lie still for a few minutes; if you are in pain, say so before the test so that pain relief can be planned [1].
Can I hold my child after a bone scan?
My bone scan was normal; does that mean the cancer has not spread?
A normal scan is good news, because a bone scan is a sensitive test [1]. But very small lesions, or lesions that only destroy bone, may not show up [1]. In high-risk prostate cancer, a PSMA PET scan finds spread more often than a CT scan and bone scan [4]. Go over the result with your doctor alongside your other tests.
Does a hot spot on a bone scan mean I have cancer?
Not necessarily. Arthritis, old or new fractures, infection and other conditions also cause hot spots [1]. Your doctor usually finds the cause with another test, such as an X-ray, CT scan or MRI [1]. See the section “Bone scan results: what does a hot spot or increased uptake mean?”.
Related pages
Method, diagnostic accuracy and role in staging (for doctors)
For physicians
Method (EANM 2016). 99mTc-labelled bisphosphonate; average adult activity 500 MBq (300–740 MBq; usually 8–10 MBq/kg) intravenously. Early images 1–10 minutes after injection (when needed) and delayed images 2–5 hours later; late images at 6–24 hours in selected cases. Adult effective dose 3–4 mSv, not counting CT (diagnostic CT of spine and hips 4–10 mSv). Breastfeeding: interrupt for at least 4 hours and discard one feed. SPECT or SPECT/CT significantly increases sensitivity and specificity. FDG PET is more sensitive for lytic metastases and bone-seeking tracers for blastic metastases. An increase in the intensity or number of foci on scans less than 6 months apart may be progression or a flare phenomenon; low or absent soft tissue uptake may result from very high avidity of the axial skeleton (a "superscan" appearance) [1].
Accuracy in prostate cancer (EAU 2026). Meta-analysis: sensitivity 79% (95% CI 73–83) and specificity 82% (78–85) at patient level; diagnostic yield depends on PSA, clinical stage and ISUP grade group; perform in symptomatic patients regardless of PSA, ISUP grade group and stage. Recommendations: low and favourable intermediate risk: no additional staging imaging (strong); unfavourable intermediate risk: PSMA PET/CT if available, or at least cross-sectional abdominopelvic imaging and a bone scan (weak); high-risk/locally advanced: PSMA PET/CT if available, or at least cross-sectional abdominopelvic imaging and a bone scan (strong) [3].
proPSMA (302 high-risk men). Accuracy of PSMA PET-CT 92% (95% CI 88–95) versus 65% (60–69) for CT plus bone scan (difference 27%; P<0.0001); sensitivity of conventional imaging 38% versus 85% and specificity 91% versus 98%; equivocal findings 23% versus 7%; management change 15% versus 28%; radiation exposure 19.2 versus 8.4 mSv [4]. In MITNEC-A1 (261 patients with high-risk prostate or breast cancer), patient-level accuracy of 18F-NaF PET-CT was 84.3% versus 77.4% for 99mTc-MDP SPECT (difference 6.9%; P=0.016) [6].
Breast cancer. ASCO "top five" list: do not perform PET, CT or bone scans to stage early breast cancer at low risk of metastasis (asymptomatic DCIS and clinical stage I and II), as there is no evidence of benefit [5].
Related cancer types
Related questions
References
9 referencesShow all references, 2 with a study cardClose the reference list
Numbers in the text, such as [1], refer to these sources. Sources with a “Study card” button are summarised in the site’s evidence library.
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- 9Management of Osteoporosis in Survivors of Adult Cancers With Nonmetastatic Disease: ASCO Clinical Practice Guideline
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