Health & Fitness

Using your immune system to fight cancer is showing significant promise

Dr. Bruno Bastos, an oncologist with the Maroone Cancer Center at Cleveland Clinic Florida.
Dr. Bruno Bastos, an oncologist with the Maroone Cancer Center at Cleveland Clinic Florida.

What if the power to fight cancer more effectively was within you? Researchers are trying to harness that superpower, by studying how a patient’s own immune system battles cancer.

“Immunotherapy is a more natural way of treating cancer, rather than attacking the cancer cells with chemicals,” said Dr. Bruno Bastos, an oncologist with the Maroone Cancer Center at Cleveland Clinic Florida. “Immunotherapy allows the patient's own immune system to do the job it is supposed to do, which is to fight the cancer.”

Drugs, vaccines and clinical trials are being developed to help doctors find ways to boost the immune system. “We are all fighting cancer every day. Our bodies are always fighting,” Bastos said. “But cancer cells create a checkpoint, a shield, that block the immune system’s efforts to fight them.”

One type of immunotherapy removes that shield, so the immune system can fight cancer cells, he said. “What's exciting is that patients can get cancer treatment with minimal side effects,” Bastos said.

Immunotherapy is currently FDA approved for several types of cancer, but studies are ongoing, said Dr. Luis Raez, chief of hematology/oncology and medical director of Memorial Cancer Institute, part of Memorial Healthcare System in Broward County.

Memorial is studying how to find markers in the blood to determine if a patient is more receptive to immunotherapy. “This is very challenging, because nowadays the decision is based on tissue, and sometimes there is not enough tissue, or the tissue has been used for other tests,” Raez said. “We are trying to isolate and identify the markers for immunotherapy in the blood, to see which patients are the best candidates.”

Here are some advances in immunotherapy at local hospitals:

Lymphoma

A type of immunotherapy that genetically engineers a patient's own immune cells to better fight cancer has been successfully used in clinical trials at the Sylvester Comprehensive Cancer Center at the University of Miami Health System.

A recently concluded study treated 111 lymphoma patients who had not responded well to standard treatment. In the trial, a patient’s T cells, which are part of the immune system, were extracted from the blood and genetically modified to recognize a specific protein on cancer cells. The modified cells, called CAR T cells, were grown to large numbers outside of the body, then infused back into the patient to attack the cancer.

"It’s like if you told someone to go into a crowd and pick out everyone wearing a red jacket. That's how these therapies work,” said Dr. Krishna Komanduri, a blood cancer expert at Sylvester. “They recognize and destroy only cells that have a specific protein on their surface.”

Before the study, the patient group had very little chance of survival, because of poor response to prior treatment, he said. With more chemotherapy, typical results would be 20 percent of patients having a 50 percent reduction in tumor volume, and less than 10 percent having the disease completely go away, Komanduri said.

The study showed impressive results, he said, with 82 percent of patients having a 50 percent reduction in tumor volume, and 54 percent of all patients seeing the cancer completely go away.

“It is one of the most important immunotherapy studies done in cancer. The results are so dramatic, the FDA is now looking at approving CAR T cells as a treatment for lymphoma patients who are not responding to other treatment,” he said. “Technically the study has closed, but Kite Pharma is allowing us to continue to treat patients as the FDA reviews their application.”

Sylvester also has T cell immunotherapy studies open for sarcoma, other types of lymphoma, and ovarian, lung and liver cancers.

CAR T cell therapy has shown the most impressive results in blood cancers like aggressive, b-cell lymphoma, or acute lymphoblastic leukemia, known as ALL, the most common form of pediatric leukemia.

“There also have been isolated, dramatic responses in other diseases, including brain cancer,” Komanduri said.

CAR T cell therapy also may have long term benefits. “When cells are infused, they are living, so they can not only recognize and kill their target, they can divide and proliferate, and in some cases persist for months or longer, providing long-lasting immunity,” he said. “We have a completely different form of therapy, which has never really existed, and I think that these results in lymphoma demonstrate a really broad potential.”

Ewing’s Sarcoma

Nicklaus Children’s Hospital is recruiting patients ages 2 through adulthood with recurrent Ewing’s Sarcoma for a clinical trial of a personalized vaccine to help the immune system target cancer.

Ewing’s Sarcoma is a rare cancer in which a tumor can present either inside or outside of bone, said Dr. Guillermo DeAngulo, a pediatric oncologist at Nicklaus. To be eligible for the trial, patients must have had a tumor reoccur after treatment for Ewing’s Sarcoma.

In the study, diseased tissue will be removed at Nicklaus and sent to a lab in Dallas to create a monthly vaccine. Nicklaus is one of 10 hospitals nationwide and the only one in Florida conducting the trial.

“The idea is that the vaccine will target the tumor,” DeAngulo said. “When you inject a vaccine and stimulate the immune system, the idea is to give it a target,” he said. “If you have a target for the attack, you have an educated form of therapy, so you don’t have a lot of the typical side effects that you see with conventional chemotherapy.”

When you target a tumor, instead of giving medicine that goes after all dividing cells, you decrease side effects, DeAngulo said. “Cancer cells are cells that should no longer be dividing, but are undergoing cell division rapidly,” he said. “At the same time, you have a lot of healthy cells that are undergoing cell division, such as your blood, hair and mucus membranes. If you can give a therapy that just targets the cells in tumors, you will no longer affect healthy, dividing cells.”

Lung cancer

At Cleveland Clinic Florida, patients with early stage lung cancer, stages 1, 2, or 3, are being recruited for a trial that uses immunotherapy after surgery. In the study, after the cancer is surgically removed, all patients receive chemotherapy. Then in a randomized process, some patients will return every two weeks for immunotherapy for a year. The remaining patients will receive routine care.

Studies on the horizon may test other combinations of treatment, said Bastos of Cleveland Clinic. This trial studies the effectiveness of chemotherapy alone, along with the combination of chemo and immunotherapy, he said. "It would be interesting to see if immunotherapy alone does as well as chemo plus immunotherapy," Bastos said. A future study will look at radiation and immunotherapy. Other trials will soon open for stage 4 lung-cancer patients, Bastos said.

At Memorial, there are immunotherapy clinical trials for patients with tumors, those who have had surgery, and even those with immunotherapy-resistant tumors, said Raez of Memorial. Memorial also has participated in clinical trials for each of the three FDA-approved immunotherapy drugs for lung cancer.

In May, the FDA approved immunotherapy drug Keytruda to be used in combination with chemotherapy for lung cancer. "This is significant because immunotherapy is moving from second line (therapy) to first line," Raez said.

Giving the immunotherapy in combination with chemo to new patients with non-small cell lung cancer is a big step, he said. “That's very significant because it gives them the benefit from both from the beginning,” Raez said. “It is better than immunotherapy alone, or chemo alone.”

To find clinical trials

Sylvester Comprehensive Cancer Society at the University of Miami Health System: Sylvester.org or 305-243-1000

Nicklaus Children’s Hospital: Nicklauschildrens.org or 305-666-6511

Cleveland Clinic Florida: Clevelandclinicflorida.org or 954-487-2258

Memorial Health System: Mhs.net or 954-265-1847

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