With intravesical therapy, the doctor puts a liquid drug right into your bladder rather than giving it by mouth or injecting it into your blood. The drug is given through a tube (urinary catheter) that's been put into your bladder through your urethra.
When is intravesical therapy used?
Intravesical therapy is used mainly for some early-stage bladder cancers that are still only in (or very close to) the inner lining of the bladder (where almost all bladder cancers start). Drugs given directly into the bladder affect the cells lining the inside of the bladder and have little to no effect on cells elsewhere. This means that any cancer cells outside of the bladder lining, including those that have grown deeply into the bladder wall, aren’t treated by intravesical therapy. Drugs put into the bladder also can’t reach any cancer cells in other parts of the body.
To treat non-muscle invasive bladder cancer (NMIBC)
These early-stage cancers have not grown deep enough to reach the muscle layer of the bladder wall (nor have they spread to other parts of the body). They are:
- Only in the inner lining of the bladder (called carcinoma in situ (CIS) or stage 0 cancer), or
- Have grown only into the layer below the lining (stage I bladder cancer)
Most often, intravesical therapy is used after transurethral resection of bladder tumor (TURBT). A dose of intravesical chemotherapy (see below) is usually given within 24 hours of the procedure.
If further intravesical treatments (immunotherapy or chemotherapy) are needed, they're usually started a few weeks later. Treatment schedules vary, depending on the risk of the bladder cancer coming back after treatment, which treatment is used, how well the cancer responds to the treatment, and other factors. For some low-risk cancers, no further treatment might be needed. For higher-risk cancers, intravesical therapy might be given weekly (or less often) for up to 3 years. Your doctor will talk with you about the best plan based on the details of your bladder cancer and how it responds to treatment.
To treat higher-stage, invasive bladder cancers
These cancers have reached the muscle layer of the bladder wall. If a transurethral resection of bladder tumor (TURBT) is done as the initial surgery (which isn’t often), a dose of intravesical chemotherapy is often given within 24 hours. But intravesical therapy isn’t likely to be helpful for most stage II or higher bladder cancers because they have already spread beyond the inner lining of the bladder wall.
Sometimes if surgery can’t be done for a stage II or III bladder cancer for some reason, chemotherapy (given into the blood) and radiation therapy might be the first treatments, after which intravesical immunotherapy might be used if the cancer has shrunk enough. More advanced bladder cancers are rarely treated with intravesical therapy.
Types of intravesical therapy
There are 2 main types of intravesical therapy:
- Immunotherapy
- Chemotherapy
Intravesical immunotherapy
Immunotherapy causes the body’s own immune system to attack the cancer cells.
Bacillus Calmette-Guerin (BCG)
BCG is the most common intravesical immunotherapy for treating early-stage bladder cancer.
BCG is a germ that's related to the one that causes tuberculosis (TB), but it doesn’t usually cause serious disease. When BCG is put into the bladder as a liquid through a catheter, it helps "turn on" the immune system cells there, which then attack the bladder cancer cells.
Side effects of BCG: Treatment with BCG can cause a wide range of symptoms. It's common to have flu-like symptoms, such as fever, aches, chills, and fatigue, which can last for 2 to 3 days after treatment. It also commonly causes a burning feeling in the bladder, the need to urinate often, and even blood in the urine.
While getting BCG doesn’t usually make people very sick, serious BCG infections are more likely in people who have a weakened immune system, so this treatment typically isn’t recommended for these people.
If a serious infection does happen, one sign of this can be a high fever that doesn't go away. If this happens, call your doctor right away.
You might want to ask about other serious side effects you should watch for and call your doctor about.
Nadofaragene firadenovec (Adstiladrin)
This treatment is made up of a virus that contains the gene to make interferon alfa-2b, an important immune system protein. When the virus is put into the bladder as part of a liquid, it delivers the gene into the cells lining the bladder wall. The cells then start making extra interferon alfa-2b, which helps the body’s immune system attack the cancer cells. Because this treatment involves adding a gene to some cells in the body, it can be thought of as a type of gene therapy.
Adstiladrin can be used to treat NMIBC that is at high risk of returning and that isn’t being helped by treatment with BCG. It is typically given once every 3 months.
Side effects of Adstiladrin: Some people getting this treatment might have side effects such as feeling tired, having bladder spasms, feeling the need to urinate often, or having blood in the urine.
The virus used in this treatment doesn’t usually cause disease in people with normally functioning immune systems – it’s just a way to get the gene inside the cells. Still, this is a live virus that might cause more serious infections in people who have weakened immune systems. Because of this, this treatment typically isn’t recommended for people with a weakened immune system.
Intravesical chemotherapy
For this treatment, chemotherapy (chemo) drugs are put right into the bladder through a catheter. These drugs kill actively growing cancer cells. Many of these same drugs can also be given systemically (usually into a vein) to treat more advanced stages of bladder cancer. Intravesical chemotherapy is most often used when intravesical immunotherapy doesn't work.
The chemotherapy solution might be heated up before it's put into the bladder. Some experts believe that this makes the drug work better and helps it get into the cancer cells. When the chemo is heated, it might be called hyperthermic intravesical therapy.
Mitomycin and gemcitabine are the drugs used most often for intravesical chemotherapy. Delivery of mitomycin into the bladder along with heating the inside of the bladder, a treatment called electromotive mitomycin therapy, may work even better than giving intravesical mitomycin the usual way.
Valrubicin or other chemo drugs might also be options in some situations.
Side effects of intravesical chemo: The main side effects of intravesical chemo are irritation and a burning feeling in the bladder, and blood in the urine.
A major advantage of giving chemo right into the bladder instead of injecting it into the bloodstream is that the drugs usually do not reach and affect other parts of the body. This helps people avoid many of the side effects linked to chemo.
