What is Neurotoxicity?
- CAR T-cell therapy modifies your immune cells to make them more effective cancer fighters.
- One possible side effect, called neurotoxicity, can affect your brain and cause symptoms such as confusion or seizures.
- Doctors monitor for this side effect, and treat it when necessary.
While CAR T-cell therapy can offer a lot of hope to people whose cancer has been resistant to other treatments or that has come back following treatment, there are some risks you should know about before you make the decision to undergo this therapy.
Read MoreWhat Causes Neurotoxicity?
Researchers don't fully understand the answer to that question. What happens after CAR T-cell therapy is that the modified T cells, which have been engineered to find and destroy your cancer, make their way into your brain and spinal cord.
Those cells stimulate the release of immune system chemicals called cytokines, which produce inflammation. Inflammation can damage the sensitive tissues in your brain.
What It Looks Like
Symptoms of neurotoxicity can range from mild to severe. With a mild case, you may feel a little fuzzy or confused.
Rarely, neurotoxicity can be severe enough to cause seizures, reduced awareness and even coma. Even if you have mild symptoms, your doctor will take neurotoxicity very seriously, Dr. Shah says. "It is something that we need to make sure we address."
Preventing Neurotoxicity
Most of the time, this side effect improves on its own within a few weeks after treatment. But because neurotoxicity can be difficult to treat, doctors focus on preventing it. "We might start you on an anti-seizure medication, just to prevent the possibility of seizures," Dr. Shah says.
Also expect your doctor to ask you some questions that you might find silly, such as, "Who are you?", "Where are you?" and "What day is it?" But there are good reasons for asking.
"It helps us to understand that you’re completely oriented and that you’re not confused," Dr. Shah says. Your doctor might also ask your family members how you're doing and whether you've shown any signs of confusion, just to confirm that you're ok.
Treating Neurotoxicity
If you do show signs of confusionfor example, you can't remember your name or the day, and you have a low score on a mental assessment, then your doctor will suspect that you have neurotoxicity. The next step is to start you on steroid medicines.
"Why do we start steroids? Because this confusion or neurotoxicity is usually related to extreme inflammation caused by the T cells," Dr. Shah explains. She likens it to having a severe case of the flu, where you get a little confused or mentally foggy. That's essentially what it feels like to have neurotoxicity. "We try to prevent this from progressing."
Neurotoxicity isn't the only possible side effect of CAR T-cell therapy. Some people develop an immune overreaction known as cytokine release syndrome, or CRS, which causes symptoms such as a high fever, chills, extreme fatigue and difficulty breathing.
Related: Cytokine Release Syndrome and CAR T-Cell Therapy: Understanding the Risks
Before you have this treatment, go over all of the possible side effects and the likelihood that you might experience them with your doctor. Make sure you're comfortable with the risks, and that you know how your doctor will treat any side effects if they do happen to you.
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