CAR T-cell therapy

CAR T-cell therapy changes your own immune cells in a lab so they can find and kill certain blood cancers.

Rosa: Hi, I'm Rosa. CAR T-cell therapy uses your own immune cells, trained in a lab to fight certain blood cancers. Let's walk through each step together.

CAR T-cell therapy is a type of immunotherapy made from your own blood cells. It is approved in the US for certain blood cancers, such as some types of lymphoma, leukemia, and multiple myeloma. It is usually used when cancer has come back or did not respond to other treatments, though for some cancers it is now used earlier.

Your T cells are immune cells that fight infection. In CAR T-cell therapy, some of your T cells are collected and sent to a lab. There, they are given a new gene that adds a receptor, called a CAR. The CAR works like a homing device that helps the T cells find a marker on cancer cells, such as CD19 or BCMA. The changed cells are grown into millions of copies and given back to you.

The process takes several weeks. First, your blood is collected through a process called apheresis, which is a bit like donating blood. While the cells are being made, you may get treatment to keep the cancer under control. A few days before the infusion, you get a short course of low-dose chemo to make room for the new cells. The CAR T cells are then given through a vein, usually in one session.

Two important side effects can happen in the first days to weeks. Cytokine release syndrome (CRS) is a strong immune reaction that can cause fever, chills, low blood pressure, and trouble breathing. Nerve system effects, called ICANS, can cause confusion, trouble speaking or writing, shakiness, or seizures. Care teams are trained to watch for these and have medicines to treat them. Low blood counts and a higher risk of infection can last for weeks to months.

Because of these risks, you will need to stay close to the treatment center for a period of time after the infusion, and you should not drive for a while. Current US labels advise about 2 weeks for each, but your center may have its own rules. You will need a caregiver with you around the clock during this time. Rarely, new blood cancers have been reported after CAR T-cell therapy, so you will have follow-up for life.

Call your care team right away, any time of day, for fever of 100.4°F (38°C) or higher, chills, dizziness or fainting, fast heartbeat, trouble breathing, confusion, trouble finding words, unusual sleepiness, shaking, or seizures. Caregivers should call if they notice any change in thinking or behavior. If it feels very bad, call 911.

Caregiver plan

You will need a caregiver who can stay with you 24 hours a day for the first weeks. Plan this early. Ask the center about lodging nearby if you live far away.

Handwriting check

Some centers ask you to write a short sentence each day. Changes in handwriting can be an early sign of ICANS. Your caregiver can help keep track.

Wallet card

Carry the card the center gives you. Show it at any emergency room so staff know you had CAR T-cell therapy and call your treatment team.

Insurance and approval

CAR T-cell therapy needs insurance approval and is given at specialized treatment centers. Ask your team and a financial counselor to help early, since getting started can take time.

Questions to ask

Am I a candidate for CAR T-cell therapy? How long will it take to make my cells? How long must I stay near the center? What follow-up will I need afterward?

Myth: CAR T is a last resort only

Fact: For some lymphomas and myeloma, CAR T-cell therapy is now an option after just one or two earlier treatments. Ask whether it fits your situation.

Myth: CAR T works for all cancers

Fact: In the US, approved CAR T-cell therapies are for certain blood cancers. Research in solid tumors is ongoing, mainly in clinical trials.

Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.