BCG Treatment

November 25, 2024

This page was reviewed under our medical and editorial policy by Kevin G. Chan, M.D., clinical professor, division of urology and urologic oncology, Department of Surgery, City of Hope^® Cancer Center Duarte 

BCG is short for bacillus Calmette-Guérin, a type of bacteria similar to the one that causes tuberculosis. A weakened form of BCG is commonly used as an immunotherapy drug for people with early-stage bladder cancer to stop or delay its progression or reduce the likelihood of a recurrence. In general, immunotherapies work by enhancing the immune system’s natural ability to fight tumors.

What Is BCG Treatment?

BCG has long been used as a vaccine against tuberculosis, particularly in countries where that disease is prevalent. For more than 30 years, BCG has also been used as a bladder cancer treatment. It is given in the form of a liquid drug and delivered directly to the bladder through a catheter — an approach known as intravesical therapy. Once inside the bladder, BCG stimulates the immune system to attack tumor cells there.

Intravesical BCG therapy is a routine treatment for many patients with non-muscle invasive bladder cancer (tumors that have not grown deeply enough into the bladder wall to reach its layer of muscular tissue). Typically, it is given after surgery to remove the tumor, with the goal of destroying any remaining tumor cells. Compared with surgery alone, adding BCG therapy helps reduce the likelihood of early-stage bladder tumors either progressing or recurring.

BCG Treatment Procedure

BCG therapy is usually done after TURBT (transurethral resection of bladder tumor), a procedure in which the visible cancer is removed with a thin scope threaded into the bladder through the urethra (the passage through which urine flows). Before beginning BCG, patients undergo a second TURBT to confirm that the cancer has not spread to the bladder muscle, as the therapy is not appropriate for tumors that have burrowed in that deeply.

The first course of BCG (also called an induction course) is given once a week for six weeks, usually in a doctor’s office rather than a hospital. Ahead of each treatment, the patient needs to refrain from drinking fluids for four hours, then void to make sure the bladder is empty. For the procedure:

• The doctor uses a local anesthetic to numb the treatment area.
• A catheter (a thin tube) is threaded through the urethra and into the bladder.
• The liquid BCG solution is injected into the catheter.
• The patient must hold the drug in the bladder for two hours before passing it by urinating. The first hour is typically spent lying down, alternating positions every 15 minutes.
• After the first hour, it is OK to get up and move around.

Once the six-week BCG course is completed, the doctor performs tests to see whether the cancer appears to be gone. This is done with a scope inserted through the urethra to visualize the bladder, and sometimes a tissue biopsy is taken at the same time. If there is no sign of cancer remaining, patients usually continue to receive periodic BCG maintenance doses to reduce the chances of a recurrence. Those treatments may be given for one to three years, depending on whether the patient is considered to be at intermediate or high risk of recurrence.

If the BCG induction round does not eliminate evidence of cancer, a second course may be an option. About half of patients who do not completely respond to the first induction course do respond to the second, according to treatment guidelines from the American Urological Association.

BCG Treatment Side Effects

While BCG therapy is generally considered safe, about 70% of patients have side effects — and for 8%, they are serious enough to discontinue treatment. Some of the possible side effects of BCG therapy may include:

• Burning sensation during urination
• Frequent urination
• Blood in the urine
• Fatigue
• Fever/chills
• Body aches

These types of symptoms may last for two to three days after treatment. There may also be longer term complications, though they are far less common, including infections of the urinary tract or other body tissues, such as the lungs, liver and joints.

BCG Is Contagious

For a short period after each procedure, the live, weakened BCG bacterium will be present in the urine, which means it is possible to transmit it to others.

Patients are asked to take precautions. For the first six hours after treatment, patients should sit on the toilet to urinate (to avoid splashing) and then disinfect the urine with an equal amount of undiluted bleach.

After adding the bleach, let it sit for 15 minutes before flushing.