Tumor-infiltrating lymphocyte (TIL) therapy

Tumor-infiltrating lymphocyte (TIL) therapy is a type of immunotherapy that uses your own immune system to help fight cancer. Many tumors already contain immune cells (lymphocytes) that try to attack cancer, but there usually aren’t enough of them to do the job on their own. With TIL therapy, your doctor takes those immune cells, grows more of them in a lab, and then puts them back into your body to help fight the cancer more effectively.

At Penn Medicine, our experience with advanced therapies like TIL therapy is built on world-leading research, highly experienced doctors, and personalized cancer care. We offer access to innovative approaches and coordinated support, so patients receive expert care every step of the way.

TIL therapy may be an option for people who:

• Have certain types of cancer, such as melanoma or some solid tumors
• Have cancer that has not responded to other treatments
• Are healthy enough to go through the treatment and recovery process

Your Penn Medicine care team will carefully review your health, cancer type, and past treatments to see if TIL therapy is right for you.

TIL therapy begins with a procedure to remove a small piece of the tumor, which contains the lymphocytes. Unlike CAR T cell therapy, which engineers T cells from your blood to target cancer, TIL therapy uses the tumor’s own immune cells and boosts them to work more effectively. Once collected, the cells are sent to a lab, where they are carefully grown over several weeks into millions—or even billions—of cancer-fighting cells.

Before the cells are returned to your body, you’ll receive a short course of chemotherapy. This helps prepare your immune system so the TILs can work at their best. The lab-grown TILs are then infused through an IV (intravenous line), similar to a blood transfusion. You may also receive additional medicine to help keep the TILs active and strong.

Throughout the process, your care team will monitor you closely, explain what to expect, and help manage any side effects.

Recovery looks different for everyone. Many people need several weeks to regain their strength after treatment. Fatigue is common at first, but it often improves over time.

You’ll have regular follow-up visits so your care team can:

• Check how the cancer is responding
• Manage any lingering side effects
• Support your recovery and overall well-being

If you’re considering TIL therapy, it’s normal to have a lot of questions. Your Penn Medicine care team is here to explain each step and support you and your family throughout your treatment journey.