At a glance
A PET scan (Positron Emission Tomography) is an imaging test that shows how tissues and organs in your body are working at a cellular level, not just what they look like.
Before the scan, a small amount of a radioactive tracer, a sugar-like substance that cells absorb, is injected into a vein. Cancer cells and other highly active cells consume more of this tracer than normal cells do, so they appear as bright spots on the image. A computer then builds a detailed map of activity across your body, helping doctors locate tumours, see how large they are, and check whether cancer has spread to other areas.
Medical Condition
Doctors order a PET scan when they need to understand how active a disease is, not just where it sits. It is used most often in oncology (cancer medicine) and nuclear medicine.
- Detecting cancer that is suspected but not yet confirmed, or finding where it has spread (metastasis)
- Staging cancer, meaning deciding how far along the disease is before treatment begins
- Checking whether a tumour is responding to chemotherapy or radiotherapy
- Finding cancer that has come back after treatment (recurrence)
- Evaluating brain conditions such as epilepsy (repeated seizures) or dementia (progressive memory loss), when other scans are inconclusive
- Assessing heart muscle that may be alive but not pumping well, to guide decisions about cardiac surgery
A PET scan is generally not used when a simpler test such as an ultrasound or CT scan can answer the clinical question adequately. It is also avoided in pregnancy unless the benefit to the mother clearly outweighs the very small radiation exposure to the baby. Patients with very high blood sugar at the time of the scan may get unclear images, so doctors usually reschedule if diabetes is poorly controlled on the day.
- Pregnancy, unless medically urgent
- Uncontrolled high blood sugar (hyperglycaemia) on the day of the scan
- Breastfeeding mothers, who are usually asked to pause nursing for a short period after the scan
- Patients who cannot lie still for the full duration of the scan
Risks & Complications
A PET scan is a low-risk diagnostic test. The radiation dose is small and leaves your body within hours, and the procedure involves no surgery or incisions.
- Mild discomfort or bruising at the injection site where the tracer is given
- Allergic reaction to the radioactive tracer, which is rare and usually mild (flushing, rash, or nausea)
- Small amount of radiation exposure, comparable to what is used in some CT scans; the body clears it naturally
- Slightly unclear images if blood sugar is elevated on the day, which may mean the scan needs to be repeated
- Anxiety or claustrophobia (discomfort in enclosed spaces) inside the scanner, which staff can help manage
- In breastfeeding women, a brief pause in nursing is needed to avoid passing any tracer to the baby through breast milk
Preparation & Procedure
Getting ready for a PET scan takes a bit more planning than most imaging tests, mainly because your blood sugar level directly affects the quality of the images.
Most hospitals ask you to stop eating and drinking anything other than plain water for four to six hours before the scan. You should avoid strenuous exercise for at least 24 hours beforehand, because active muscles take up the tracer and can confuse the results. If you take metformin or other diabetes medications, your care team will advise you on adjusting them in the days leading up to the scan. Tell the team about any medications you take, including blood thinners, as some may need to be paused. Avoid caffeine and alcohol for at least 24 hours before.
Wear comfortable, loose clothing without metal (zips, underwire bras, and belt buckles can interfere with the images). Leave jewellery at home. Arrive on time, as the tracer must be prepared fresh for each patient and delays affect the whole schedule.
Before the scan, your team will usually check your blood sugar with a simple finger-prick test to make sure it is in a suitable range. Some centres combine the PET scan with a CT scan (called a PET-CT) taken at the same session, which adds detail about the exact location and shape of anything the PET finds.
- Step 1: You arrive and your blood sugar is measured. If it is too high, the scan may be rescheduled.
- Step 2: A small needle is placed in a vein in your arm, and the radioactive tracer is injected. The injection itself takes only a few seconds.
- Step 3: You wait quietly in a reclining chair for about 45 to 90 minutes while the tracer spreads through your body. You are asked to stay still and avoid talking, as muscle movement changes where the tracer collects.
- Step 4: You lie on a flat, padded table that moves slowly through the PET scanner, a large ring-shaped machine. The scan itself usually takes 20 to 45 minutes, though this varies.
- Step 5: If a combined PET-CT is being done, the CT part is usually taken immediately before or after, in the same session.
- Step 6: The needle is removed. You can usually eat, drink, and move normally straight away. The radiologist (imaging specialist) analyses the images, and results are sent to your referring doctor, usually within a few days.
Aftercare
Recovery from a PET scan is straightforward. Because no surgery is involved, most people leave the imaging centre within minutes of the scan finishing and feel completely normal for the rest of the day.
- Drink plenty of water for the rest of the day. This helps your kidneys flush the radioactive tracer out of your body more quickly.
- You can eat normally as soon as the scan is done.
- Avoid prolonged close contact with pregnant women, babies, and young children for the rest of the scan day, as a small amount of radioactivity remains in your body. By the next day, this is no longer a concern.
- If you are breastfeeding, your nuclear medicine team will tell you how long to pause nursing before resuming.
- You can drive yourself home and return to work or normal activities the same day in most cases.
- Results are interpreted by a radiologist and passed to your referring doctor, who will discuss findings with you at a follow-up appointment. Ask when and how you will receive your results before you leave.
- If you felt any discomfort at the injection site, mild warmth or a cool cloth usually helps. Report any redness, swelling, or pain that worsens over the following day to your care team.
- No wound care, stitches, or special diet is needed after the scan.
Cost & What Determines It
A PET scan is one of the more expensive imaging tests available, and the price can differ substantially from one hospital or country to another. The gap exists because several factors are specific to how each centre operates and how complex your individual case is.
- Type of scan ordered: a standard PET scan costs less than a combined PET-CT or PET-MRI, which are more information-rich but also more resource-intensive
- The radioactive tracer used: different tracers are used for cancer, heart, or brain studies, and some are significantly more expensive to produce than others
- Body area covered: a scan of the whole body from head to thigh costs more than a scan limited to one region
- Hospital class and country: pricing at a private specialist centre, a university hospital, or a facility in a higher-income country will differ considerably
- Whether the scan requires an anaesthesiologist or sedation, for patients who cannot stay still
- Radiologist fees for interpreting and reporting the images, which may or may not be bundled into the scan price
- Any blood tests, particularly a blood sugar check, done on the same day
- Follow-up consultation with a specialist to discuss the results
A hospital package for a PET scan typically covers the tracer preparation and injection, the scan time itself, and the radiologist's written report. Items that are often billed separately include the specialist consultation to discuss results, additional imaging taken in the same session, sedation if needed, and any follow-up blood tests ordered after the scan.
BPJS Kesehatan does not cover medical procedures performed abroad, and most Indonesian private health insurance policies also exclude overseas treatment. Patients who choose to have a PET scan in another country usually pay out of pocket or through an international private health insurance plan that specifically covers treatment abroad. Before travelling, ask the hospital for a written cost estimate that itemises every component of the scan and the consultation. This document protects you from unexpected charges and allows you to compare offers from different hospitals accurately.
Frequently Asked Questions
Does a PET scan hurt?
A PET scan is not painful. A small injection of a tracer (a mildly radioactive sugar solution that helps the scanner detect abnormal activity in your body) is given through a vein before the scan, which may feel like a brief pinch. You then lie still inside the scanner, which makes no contact with your body.
How do I prepare for a PET scan, and do I need to fast?
Most patients are asked to fast for about four to six hours before the scan, because eating raises your blood sugar and can interfere with how well the tracer is absorbed. Your medical team will also usually ask you to avoid strenuous exercise for a day or two beforehand and to drink plenty of water on the day. Always follow the specific instructions given by your hospital, as preparation can vary slightly depending on which part of the body is being examined.
How long does a PET scan take?
The full appointment usually takes two to three hours in total. This includes a waiting period of roughly one hour after the tracer injection to let it spread through your body, followed by the actual scanning, which typically lasts between twenty and forty minutes. You can usually go home shortly after the scan is finished.
How much does a PET scan cost?
The cost of a PET scan depends on several factors, including the hospital class, whether the scan covers one area or your whole body, and whether a combined PET-CT (a scan that pairs the PET with a detailed X-ray image) is requested. A written cost estimate from the hospital is the most reliable way to know what you will be paying before you travel.
This page is general information, not a substitute for medical advice. Every case is different. Your doctor decides what is right for you.
