An Imaging Test Can Spot the Transformation
- A slow-growing lymphoma can transform into a more aggressive form of the disease
- PET/CT scan is an imaging test your doctor will use to see if your cancer has changed
- This test highlights problematic lymph nodes for your doctor to biopsy
“Where I use PET/CT in my practice quite a bit is if I’m observing a patient … and there is some new symptom or situation which makes me concerned that the patient may be changing from an indolent lymphoma to a more aggressive lymphoma,” Dr. Jakub Svoboda, medical oncologist at Penn Medicine, tells SurvivorNet. “We refer to it as transformation.”
Which Lymphomas Transform?
Read More- Chronic lymphocytic leukemia/small lymphocytic lymphoma can transform into diffuse large B-cell lymphoma or Hodgkin lymphoma
- Follicular lymphoma can transform into diffuse large B-cell lymphoma or aggressive B-cell lymphoma
- Mantle cell lymphoma (MCL) can transform into blastic (or blastoid) MCL
- Marginal zone lymphomas (MZL) can transform into diffuse large B-cell lymphoma
How PET/CT Finds a Transformation
If your doctor suspects there’s been a change to your cancer — for example, because you’ve started to have symptoms — he or she might send you for a positron emission tomography (PET)/computed tomography (CT) scan. This test combines two imaging tests in one.
A CT scan takes x-rays of your body from many different angles. Then a computer combines them to make cross-sectional images. A CT scan can identify areas where your cancer has grown.
A PET scan starts with an injection of a small amount of a radioactive sugar called fluorodeoxyglucose-18 (FDG-18). Cancer cells are more metabolically active than healthy cells, so they take up more of the radioactive sugar. The areas of cancer essentially light up on a computer screen. When the PET and CT scans are combined, they create very detailed, three-dimensional images of any abnormal lymph nodes.
Finding the Right Nodes
A lymph node biopsy is the only way to confirm that your cancer has undergone a transformation. Looking for active areas on the PET/CT scan can point your doctor to the right lymph nodes to biopsy.
Doctors use a measurement called standard uptake value (SUV) to show how much radioactive sugar the lymph nodes have taken up. The higher the number, the more abnormal the tissue. “So if the SUV is 15 in the armpit and three in the groin, you really want to take out the lymph node from the armpit, because that may provide the most useful information,” Dr. Svoboda says.
Your doctor will remove all or part of a suspicious lymph node and send the sample out to a lab, where a pathologist will look at it under a microscope. “The lymph node will look different under the microscope when the disease is transformed into more aggressive lymphoma,” Dr. Svoboda adds. If your cancer has undergone a transformation, the pathologist will see large, fast-growing cancer cells in your biopsy sample.
At that point you’ll have a conversation with your doctor about starting treatment, or switching to a more aggressive therapy. Transformed lymphoma is treated differently than indolent lymphoma, often with chemotherapy-drug cocktails tailored to the new aggressive lymphoma. It may require a stem cell transplant.
Learning that your once slow-growing cancer has transformed into something more aggressive can be worrisome. You may be contemplating treatment, along with the side effects it can bring, for the very first time since you were diagnosed. Remember that your cancer is still manageable. Give yourself time to wrap your head around your new situation, and make sure that you fully understand all of the treatments that are available to you.
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