BCG-Unresponsive Bladder Cancer Defined
The most common treatment for non-muscle-invasive bladder cancer (NMIBC) is called Bacillus Calmette-Guérin (BCG). BCG involves filling the bladder with a live strain of the bacteria Mycobacterium bovis, which works to fight the cancer.1-3
BCG is currently the only FDA-approved treatment for NMIBC that takes place in the bladder itself. Treatments like bladder removal surgery are also effective, but BCG replaced surgery as the leading NMIBC treatment in the mid-1980s. BCG does not involve bladder removal, so many doctors and people with NMIBC prefer it.1,3
Though BCG has been shown to help 70 percent of people with NMIBC who are good candidates, it does not work for everyone. Because it is the primary treatment for NMIBC, other treatments may not be as well-known. But there are alternatives when BCG treatment does not work for a person with NMIBC.1
What is BCG?
BCG is a type of therapy where a solution of bacteria is placed in the bladder with a catheter or a slow drip (instillation). A person holds this solution inside for about 2 hours before urinating it out. Multiple cycles of instillation are done to kill off as much of the tumor as possible.1
How can bladder cancer be "unresponsive" to BCG?
BCG does not work for everyone who tries it. Treatment effectiveness varies from person to person. About one-third of people with NMIBC who do BCG therapy do not respond to it. The reasons for this are not fully understood.2
BCG unresponsiveness is defined by at least one of the following:2
What are my options if my cancer is not responsive to BCG?
People whose cancer does not respond to BCG are unlikely to benefit from trying BCG again. Because of this, it is important for doctors to find other treatment options that do work for people. Some newer lines of research have shown great promise. Experts are trying to find a treatment that will help as many people as possible.2-4
Bladder removal surgery is the primary treatment for BCG-unresponsive NMIBC because it is so effective. However, the goal of treatment for people with BCG-unresponsive NMIBC is to avoid bladder removal surgery. This is because removing the bladder can damage a person's body and quality of life.2,3
Different chemotherapy drugs can be used in the bladder and have similar results to BCG in people with medium-risk and low-risk NMIBC. Most of the research into chemotherapy in the bladder looks at using a combination of multiple drugs to increase effectiveness. However, no clinical study has been done yet.3
Immunotherapy using pembrolizumab was approved for people with NMIBC by the U.S. Food and Drug Administration (FDA) in January 2020. Pembrolizumab is a drug that uses antibodies to fight tumors. Though it was not evaluated specifically in people with BCG-unresponsive NMIBC, experts are learning more about how it could help.3
BCG plus other agents
Researchers are looking into whether adding other agents or treatments can make BCG more effective for people whose cancer was not responsive to it the first time. Using a small electric current on the abdomen to move more BCG into the tissue (ElectroMotive drug administration) is an example. Supplementing BCG with other drugs is also becoming more common. But nothing has been approved by the FDA yet.3,4
There is still a lot to be learned about all of these treatments, their side effects, and how well they can treat BCG-unresponsive NMIBC. Talk to your doctor and care team about what types of treatment could be right for you.
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