Tumor-Infiltrating Lymphocyte (TIL) Therapy

About Tumor-Infiltrating Lymphocyte (TIL) Therapy

Tumor-infiltrating lymphocyte (TIL) therapy is used to treat some advanced cases of melanoma, an aggressive skin cancer. Researchers are studying how they might use TIL therapy to treat other types of cancer, but it is currently only available for melanoma.

When melanoma returns or spreads through a person’s body, it’s often treated using therapies like checkpoint inhibitor drugs or surgery. If these do not work, the patient may be out of options. TIL therapy can provide a lasting treatment option for patients who meet certain criteria.

To have TIL therapy, a patient must:

• Have melanoma that has spread to other parts of the body (metastasized)
• Have exhausted all other therapies first
• Have a tumor that can be removed surgically
• Be able to physically tolerate surgery, chemotherapy and infusion of Interleukin-2 (IL-2), a protein that helps grow more lymphocytes
• Not be using steroids
• Not have certain kinds of brain metastases

Even if a patient meets all the criteria above, their lymphocytes may not be available or suitable for TIL therapy. Your doctor will need to perform more testing to determine if you are a candidate.

How it works

The goal for TIL therapy is to encourage your own immune system to attack your tumor. Lymphocytes are a type of white blood cell that recognizes and kills mutated or infected cells, such as tumor cells. They are like your immune system’s army. Some lymphocytes enter the tumor and try to destroy it, but there aren’t enough of them to finish the job. In this case, your doctor may be able to perform TIL therapy to collect some successful lymphocytes that have infiltrated the tumor and multiply the army.

If you are a candidate, TIL therapy works like this:

1. You have surgery to remove your tumor(s).
2. A lab collects lymphocytes that have successfully attacked the tumor (called tumor-infiltrating lymphocytes).
3. In the lab, the TILs are grown using a protein called interleukin-2 (IL-2) until there are billions of these immune cells available.
4. You undergo lower-dose (non-myeloablative) chemotherapy to temporarily clear away some of your old T cells and make room for the reinforcements.
5. You receive your new TILs and then several doses of IL-2 to encourage the new lymphocytes to grow and thrive in your body.

In studies of patients whose cancer had stopped responding to treatment, about 30% responded to TIL therapy. Since TIL therapy uses your own lymphocytes, you only need one round of treatment, and the results seem to last for some patients. The longest response for patients in initial studies is five years.

At IU Health Cancer Center, each patient’s TIL therapy is monitored and discussed at the weekly tumor board conferences, where a group of cancer doctors reviews cases together. By evaluating your case from all angles, your care team can ensure you receive the best, most personalized treatment.

What to Expect with TIL therapy

There are specific requirements to undergo TIL therapy. Some patients who meet these requirements may still be unable to undergo TIL therapy. This could be because they do not have lymphocytes available in their tumor, or the tumor suppresses all the lymphocytes or the person’s health becomes too poor to undergo surgery or chemotherapy. This is why it is important to be evaluated for TIL therapy as soon as possible to ensure you are a candidate early.

When you come to IU Health for TIL therapy evaluation, you will meet with a medical oncologist and a surgeon who specialize in treating melanoma. They will talk to you about whether you are a candidate for this treatment and discuss a plan for your care.

Side effects

Undergoing TIL therapy means you’ll face potential side effects from surgery and chemotherapy. Surgery side effects can include pain, lymph node swelling or infection. Most of the risks from this therapy come from chemotherapy and IL-2 infusion, which can cause nausea, vomiting, fever, chills, loss of appetite, dizziness, shortness of breath and other issues. There can be life-threatening complications from TIL therapy, so you will be hospitalized when undergoing this treatment to allow your care team to monitor you closely.

Preparing for TIL Therapy

Your TIL therapy treatment begins with surgery to remove your tumor and check it for lymphocytes. You will need to have a tumor available for this step, so it’s important to discuss TIL therapy with your doctor before having a tumor removed.

It takes about 32 days for the laboratory to process and grow your lymphocytes. If the process is successful, you will return to IU Health for chemotherapy. This might be done as outpatient treatment, which means you may not stay overnight in the hospital. Chemotherapy is followed by a few days of rest, so this part of the process can take about a week.

Next, you return to IU Health for TIL infusion, which means using an IV to deliver it directly into your blood. Care teams in the IU Health Bone Marrow Transplant and Cellular Therapy Program deliver this treatment, which takes a few hours to complete. After the TIL infusion, you’ll receive IL-2 immunotherapy to help the lymphocytes grow. This process may take seven to 10 days or more as your care team monitors you for any toxicity or side effects.

After Your Procedure

After you leave the hospital, your doctors will monitor you for several weeks. IU Health has a structure in place to continue monitoring your recovery and coordinating care with your doctor, especially if you do not live near Indianapolis.

Questions to Ask

• If my current treatment isn’t working, am I a candidate for TIL therapy?
• How do I begin the process for undergoing TIL therapy?
• Do I need to have my tumor removed now, or can it be used for TIL therapy?