What is BCG treatment?

Some people may know BCG as a vaccine used to prevent tuberculosis (TB). But it is also a main treatment for non-muscle-invasive bladder cancer.

BCG is a type of immunotherapy drug. Immunotherapy drugs encourage the body’s immune system to fight cancer cells. For bladder cancer, BCG is given directly into the bladder (intravesical). This can make the bladder react in a way that makes the immune system get rid of cancer cells.

When is BCG treatment used?

You may have BCG directly into your bladder after surgery to remove non-muscle-invasive bladder cancer. This type of surgery is called a transurethral resection of a bladder tumour (TURBT).

This treatment helps prevent the cancer from coming back in the bladder lining. It also reduces the risk of the cancer becoming muscle-invasive. Doctors usually suggest this treatment if you have a high-risk bladder cancer, or sometimes if you have an intermediate-risk bladder cancer.

There is usually at least 2 weeks between the surgery to remove the cancer and the start of BCG treatment. This is to give your bladder enough time to heal from the surgery.

You usually have BCG treatment once a week for 6 weeks. This is sometimes called the induction course. You may be offered more BCG treatments. This is usually called maintenance treatment.

Treatment times vary. Your doctor will explain what is best for you.

Having BCG treatment

If you are having a course of BCG directly into your bladder (intravesical BCG), you have it in the hospital outpatient department. Your nurse or doctor will give you advice on preparing for your treatment. For example, they will ask you to limit the amount of fluids you drink 4 to 6 hours before BCG treatment. This can:

  • make it easier for you to keep the BCG in your bladder for the required time (stops you needing to pass urine (pee) too early)
  • increase the concentration of the BCG drug in your bladder.

People who take water tablets (diuretics) should take them after the treatment. Tell your doctor if you take any medications.

Before you have the BCG treatment, you are asked to lie down on a couch. A nurse passes a tube (catheter) through your urethra and into your bladder. The nurse then slowly puts the BCG directly into your bladder through the catheter.

During treatment

Once the drug is in your bladder, the nurse usually takes the catheter out. They ask you not to pass urine for 2 hours. This gives the BCG time to work.

You can get up and walk around while waiting for the treatment to finish. Your bladder may feel full and a bit uncomfortable. You can go to the toilet as soon as the treatment is finished.

Sometimes, the nurse leaves the catheter in and clamps it to keep the BCG in your bladder. When the treatment is over, the nurse removes the clamp and the BCG drains from your bladder into a urine bag. Your nurse can then take the catheter out.

After treatment

It is important to remember that BCG is a live vaccine and other people should not be exposed to it. The nurse will ask you to take certain precautions for 6 hours after treatment. This will protect you and others from coming into contact with the BCG.

You will be asked to:

  • sit down to pass urine – this avoids splashing urine on the toilet seat
  • wash the skin in and around your genital area with soap and water after you pass urine – this cleans any drops of BCG that may have splashed on to your skin
  • put undiluted bleach into the toilet bowl after you have passed urine and leave it for 15 minutes before flushing
  • wash your hands carefully after passing urine with soap and water.

For about 2 days after each treatment, you will usually be asked to drink at least 2 litres (3 ½ pints) of fluid a day. This helps to flush the drug out of your bladder.

Talk to your nurse if you are worried. They will tell you what you need to do after treatment.

Side effects of BCG treatment

You may have some side effects after your treatment. These include:

  • needing to pass urine often
  • pain when you pass urine
  • blood in the urine
  • flu-like symptoms, such as tiredness, general aching and a raised temperature.

These effects should get better in 48 to 72 hours. Tell your doctor straight away if they do not get better after this time. Taking painkillers can help.

Rare side effects include:

  • a continuing high temperature (fever)
  • pain in your joints
  • a cough.

If you have any of these or feel generally unwell, tell your doctor straight away. It could be a sign of a more serious infection due to BCG that needs treatment straight away. If this happens, you will be treated with antibiotic drugs used to treat tuberculosis (TB).

Sex after BCG treatment

Men should use a condom during sex for the first week after each BCG treatment. If you are a woman having the treatment, your partner should use a condom during this time. This protects your partner from any BCG that may be present in semen or vaginal fluid. Your doctor or specialist nurse can give you more information about this.

Doctors do not yet know how BCG may affect an unborn baby. They will recommend you do not become pregnant or make someone pregnant while having it. You should use effective contraception during treatment. Your doctor or specialist nurse can give you more information about this.

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