What is intravesical therapy?
Intravesical therapy is usually an option for people with noninvasive (stage 0) or minimally invasive (stage I) bladder cancer. With intravesical therapy for bladder cancer, drugs are put directly into the bladder through a catheter, instead of being injected into a vein or swallowed. Both immunotherapy and chemotherapy drugs can be given this way.
This approach is useful for earlier stage cancers because the drugs kill malignant cells on the bladder lining only. Intravesical therapy does not reach the deeper layers of the bladder wall, the kidneys, ureters or urethra. If cancer has spread to other organs, those tumors would also not be treated with intravesical therapy.
Intravesical therapy for bladder cancer
There are a few types of intravesical immunotherapy:
- Bacillus calmette-guerin (BCG) therapy: BCG is a type of intravesical immunotherapy, and can be an appropriate way to treat early-stage bladder cancer. BCG is a bacterium that does not cause any serious disease, but is related to the germ that causes tuberculosis. For bladder cancer treatment, BCG is inserted into the bladder through a catheter. The natural immune system becomes activated by the presence of the foreign bacteria, which then affects bladder cancer cells. BCG is usually given for one to six weeks, and may be given alongside transurethral resection. Less commonly, BCG is given as a long-term maintenance treatment.
- Interferon: Several types of cells in the body produce substances called interferons, which help stimulate the immune system. These natural chemicals can also be made artificially for use as medications to treat various diseases. One application of synthesized interferon is as an intravesical immunotherapy treatment for early-stage bladder cancer.
As described above, with intravesical chemotherapy, anticancer drugs that directly kill active cancer cells are inserted directly into the bladder through a catheter. This approach helps avoid many harsh side effects that occur as a result of the drugs harming normal cells.
The drugs most commonly used in intravesical chemotherapy are mitomycin and thiotepa. Other drugs used in this approach include valrubicin, doxorubucin and gemcitabine. Sometimes, mitomycin is given as “electromotive mitomycin therapy,” which means that the bladder is heated while the drug is inserted.