How Does Immunotherapy Work?

How does immunotherapy work?  Peter H. O’Donnell, MD, from The University of Chicago, Section of Hematology/Oncology, explains immunotherapy as a bladder cancer treatment and addresses questions about how immune therapies work.
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In this video about immunotherapy for bladder cancer treatment, Peter H. O’Donnell, MD, meets with Kevin, a bladder cancer patient and his wife. They discuss the Kevin’s treatments to date, the results of his scans, and his immune therapy options as the next best treatment for his bladder cancer.

The patient’s scans show that rounds of chemotherapy did not eliminate the bladder cancer and it is growing again. Since the chemotherapy did not kill the cancer, Dr. O’Donnell offers immunotherapy, as his recommended next step. This newer IV-administered treatment is different than Bacillus Calmette-Guerin (BCG) therapy, an older bladder cancer treatment which is administered directly to the bladder.

Dr. O’Donnell explains how immunotherapy works. Animations then show bladder cancer cells, immune cells, and how they interact. A protein on the surface of bladder tumor cells allows it to hide from the body’s immune cells. As a result, the body’s blinded immune cells can’t fight and destroy the bladder cancer tumor, so it grows.

When successful, immune therapy drugs remove the surface protein signals from the cancer cells, allowing the body’s own immune cells to recognize and fight the cancer cells and shrink the bladder tumor. In addition, the immune therapy stimulates and revs up the immune cells.

Side effects of immunotherapy differ from those of chemotherapy for bladder cancer. Most people receiving immunotherapy have minimal side effects, such as rashes and tiredness. In rare instances though, the immune system gets too revved up. This can result in immune cells attacking the body’s other healthy cells in an auto-immune response. If this response occurs, the auto-immune attacks can usually be reversed with steroids.

Of the two main bladder cancer treatment options, chemotherapy, even with its bladder cancer treatment side effects, is the usual first “tried and true treatment” for a patient with a bladder cancer diagnosis.

In patients who cannot tolerate chemotherapy or for whom chemotherapy stops working, immunotherapy can be the second step standard of care for bladder tumor treatment. It has been shown to shrink tumors in 20 percent of patients, and it freezes the tumor size in another 20 percent. So almost half of patients benefit from immunotherapy. And for the patients who do benefit, the bladder tumor may not grow again for many years.

Immunotherapy is administered by IV infusion, usually in an outpatient medical center.

When chemotherapy hasn’t worked, immunotherapy can give hope to bladder cancer patients and improve bladder cancer survival.


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