BCG (Bacillus Calmette-Guérin) is a live but weakened strain of bacteria related to tuberculosis (TB). It was first developed as a TB vaccine, but doctors later discovered it could also help treat early-stage bladder cancer by boosting the immune system.
When BCG is placed directly into the bladder (via a catheter), it does two key things:
Triggers an Immune Response
The body recognizes BCG as an invader and sends immune cells (like white blood cells) to attack it.
These immune cells also attack nearby cancer cells, slowing or stopping tumor growth.
Creates Long-Term Defense
BCG helps “train” the immune system to recognize and fight cancer cells even after treatment ends.
This reduces the chance of cancer coming back.
Preparation
The patient empties their bladder before the procedure.
A doctor or nurse inserts a thin, flexible catheter through the urethra into the bladder.
Instillation (Delivery of BCG)
The BCG solution (liquid) is slowly dripped into the bladder through the catheter.
The catheter is removed, and the patient must hold the liquid in their bladder for about 1–2 hours.
After Treatment
The patient can then urinate normally (the BCG is flushed out).
To kill any remaining bacteria, patients may add bleach to the toilet before flushing.
Treatment Schedule
Induction Phase: Once a week for 6 weeks.
Maintenance Phase (if needed): Extra treatments over several months to keep cancer from returning.
BCG is mainly used for:
Non-Muscle-Invasive Bladder Cancer (NMIBC) – Cancer that hasn’t spread deep into the bladder wall.
Carcinoma in Situ (CIS) – A high-risk, early-stage cancer that looks like flat red patches inside the bladder.
After Tumor Removal Surgery – To prevent cancer from coming back.
Most side effects are mild but can include:
Common:
Burning or pain when urinating.
Frequent urination.
Mild fever or fatigue (like a mild flu).
Blood in urine (usually temporary).
Rare (but serious):
Severe infection (if BCG spreads outside the bladder).
Persistent high fever (needs medical attention).
Not Chemo or Radiation: Unlike most cancer treatments, BCG works by activating the immune system instead of poisoning cancer cells.
Highly Effective: It reduces recurrence rates by up to 50–70% in some patients.
Old but Useful: First used in the 1970s, it’s still a key treatment today!
BCG instillations are a bladder cancer treatment where weakened bacteria are placed inside the bladder to stimulate the immune system.
Given weekly for 6 weeks, sometimes longer.
Works best for early-stage bladder cancer after surgery.
Side effects are usually mild but can include discomfort and flu-like symptoms.
Learn More About: Bladder Cancer
