What should I expect during a PET scan for Leukemia

What to Expect During a PET Scan for Leukemia

A PET scan is an imaging test that can help your care team see where leukemia cells might be located in your body and how active they are. Let me walk you through what this procedure involves.

How a PET Scan Works

PET stands for positron emission tomography. During the test, a small amount of radioactive substance called a tracer (usually a glucose-based compound called FDG) is injected into a vein in your arm. Cancer cells typically use more sugar (glucose) than normal cells, so they absorb more of this tracer and show up as bright spots on the scan.

According to the NCCN Guidelines for Patients: Acute Myeloid Leukemia, a PET scan may be used if leukemia is suspected outside the blood and bone marrow (called extramedullary disease).

The Actual Procedure

Here's what typically happens:

1. Injection: A technician injects the radioactive tracer into your vein (usually in your arm)
2. Waiting period: You'll wait 30-60 minutes while the tracer circulates through your body and is absorbed by cells
3. Scanning: You'll lie on a table that slides into a PET scanner (a large, donut-shaped machine)
4. Duration: The actual scan usually takes 20-30 minutes
5. Imaging: A special camera detects the radiation and creates detailed pictures

Important Things to Know

Before your scan:

• Tell your care team about any allergies or medical conditions
• You may be asked to fast (not eat) for several hours beforehand
• Wear comfortable, loose clothing without metal (zippers, buttons with metal)
• Leave jewelry and metal objects at home

During the scan:

• You need to stay still while the camera takes pictures
• The machine makes clicking sounds—this is normal
• You won't feel the radiation
• The procedure is painless

After the scan:

• The radioactive tracer leaves your body naturally through urine and bowel movements
• You can return to normal activities immediately
• Drink plenty of fluids to help flush the tracer from your system

What the Results Mean

According to the NCCN Guidelines, cancer cells show up as bright spots on PET scans. However, it's important to understand:

• Not all bright spots are cancer — inflammation or infection can also appear bright
• Not all cancers show up on PET scans
• Normal tissues like your brain, heart, kidneys, and bladder naturally show up as bright areas

When a PET scan is combined with a CT scan (called a PET/CT scan), it provides both detailed pictures of your organs and information about where cells are most active.

Questions to Ask Your Care Team

Before your PET scan, consider asking:

1. Why am I having this PET scan? What specific information will it help you find?
2. Will this be a PET scan alone or a PET/CT scan? (Combined scans provide more information)
3. How long will the entire appointment take, including waiting time?
4. When will I get the results, and who will discuss them with me?
5. How will this scan affect my treatment plan? What decisions will be made based on the results?

Important Reminder

Your care team will interpret the PET scan results in the context of all your other tests (blood work, bone marrow biopsy, and other imaging). A single test doesn't tell the whole story—your doctors use all the information together to understand your leukemia and plan the best treatment for you.

This information is for educational purposes only. Always consult your healthcare team for personalized medical advice and decisions.