Key Statistics

Global Incidence: 600,000 new cases annually, and 220 000 deaths per year.

US Incidence: About 84530 new cases of bladder cancer (64730 in men and 19800 in women) will be diagnosed in 2026.

Risk: Men are four times more likely to develop bladder cancer than women and bladder cancer is the fourth most common cancer in men.

What is Immunotherapy for Bladder Cancer?

Immunotherapy is a type of cancer treatment that activates the immune system to help eradicate cancer cells. Bladder cancer has long been a model of disease for immunotherapy research.

Bladder cancer is often sorted by whether or not it has spread to the muscles. Non-muscle-invasive bladder cancer (NMIBC) is confined to the inner lining of the bladder at diagnosis. In 1990, the U.S. Food and Drug Administration approved Bacillus Calmette–Guérin (BCG) treatment, one of the earliest immunotherapies available to treat NMIBC.

What is BCG therapy?

BCG uses a weakened strain of Mycobacterium bovis, the bacterium in the tuberculosis vaccine, and delivers the bacteria directly to the bladder. The presence of the bacteria triggers an immune response, which ends up also fighting the cancer cells. BCG treatment works best for early-stage bladder cancers and, unlike some other cancer treatments, has fewer whole-body side effects.

Can BCG therapy treat other types of bladder cancer?

Muscle-invasive bladder cancer (MIBC) is when bladder cancer has spread from the lining of the bladder into the muscles that make up the bladder wall. The tumor microenvironment (TME) of MIBC, the area immediately surrounding the tumor, tends to be immunosuppressive, which means it turns off the immune system when it tries to fight the cancer. This allows the cancer to spread more easily and makes treatment more difficult. Researchers are seeking to better understand this tumor microenvironment so they can better treat MIBC.

What Bladder Cancer Treatments Are Being Developed?

Researchers at Memorial Sloan Kettering Cancer Center and Weill Cornell Medicine recently expanded our understanding of how BCG treatment works. In addition to working locally in the bladder, BCG treatment reprograms and amplifies cells in the bone marrow, which is where new immune cells are made. The researchers saw that in patients who received BCG treatment, the treatment altered stem cells and early-stage blood cells in the bone marrow, which led to new immune cells that were better at fighting tumors.

Can you combine BCG therapy with checkpoint inhibitors?

The researchers also saw that when BCG treatment was combined with checkpoint inhibitors, a type of immunotherapy that removes the brakes from the immune system, the combined treatment was better at shrinking tumors. The researchers say this has implications for immunotherapy beyond bladder cancer given that BCG treatment enhances immune responses overall.

Why some bladder cancers do not respond well to immunotherapy?

In 2026, researchers at the Ichan School of Medicine at Mount Sinai discovered that common makers for inflammation that can be detected in the blood, are linked to immune cells inside of tumors that are hijacked to shut down cancer-fighting cells. The researchers say this helps to explain why some bladder cancers do not respond well to immunotherapy. Connecting these markers of inflammation to immune dysfunction may help researchers develop future therapies.