A “chemo wash” is a common term for Intravesical Chemotherapy, a specialized, localized treatment for bladder cancer. This method involves delivering liquid chemotherapy medication directly into the bladder cavity, which is highly effective for tumors confined to the bladder lining. The goal of this targeted approach is to expose the cancer cells to a very high concentration of the drug while minimizing its circulation throughout the rest of the body.
How Intravesical Chemotherapy Works
The mechanism of intravesical chemotherapy differs significantly from systemic chemotherapy, which is typically infused into a vein. Systemic therapy travels through the bloodstream to target cancer cells throughout the body, often leading to widespread side effects. Conversely, the “chemo wash” delivers the drug through a catheter directly into the bladder, keeping the treatment concentrated exactly where the cancer resides.
This localized delivery is effective because bladder cancer often begins in the urothelium, the innermost layer of the bladder wall. By instilling chemotherapy agents—such as Mitomycin C or Gemcitabine—directly into the bladder, the drugs are absorbed into the superficial layers where the cancer cells are located. The high concentration allows the drug to kill these cells directly.
Because the drug has minimal absorption into the bloodstream, it largely avoids the systemic toxicity associated with traditional chemotherapy, such as nausea or hair loss. The treatment acts by disrupting the growth and division of cancer cells lining the bladder. This targeted action helps prevent the cancer from recurring.
Bladder Cancer Types Treated by This Method
Intravesical chemotherapy is primarily used to treat Non-Muscle Invasive Bladder Cancer (NMIBC), which accounts for about 70% of new bladder cancer diagnoses. NMIBC is cancer confined to the inner lining of the bladder, including stage Ta, stage T1, and carcinoma in situ (CIS) tumors.
The therapy is often administered immediately following transurethral resection of bladder tumor (TURBT), which surgically removes the visible tumor. This immediate dose, typically given within 24 hours of surgery, is designed to eliminate any residual cancer cells floating in the bladder. This prophylactic measure reduces the risk of recurrence.
For patients with intermediate-risk NMIBC, a course of intravesical chemotherapy may be recommended as adjuvant therapy to prevent recurrence. In contrast, muscle-invasive bladder cancer (MIBC), which has penetrated the deeper muscle layer, requires more aggressive treatments, such as systemic chemotherapy, radiation, or surgical removal of the bladder.
The Step-by-Step Treatment Procedure
Preparation involves restricting fluid intake for several hours before the appointment so the chemotherapy drug is not diluted by urine. Patients must also empty their bladder completely just before treatment begins. This ensures the highest possible concentration of the medication is maintained during the dwell time.
The treatment starts with a healthcare professional inserting a small, flexible tube called a catheter through the urethra into the bladder. Once the catheter is in place, the liquid chemotherapy drug is slowly instilled into the bladder through the tube, which takes only a few minutes. The catheter is then typically clamped or removed.
The chemotherapy agent must remain in the bladder for a specific period, known as the “dwell time,” which is usually between one and two hours. Patients may be asked to change positions—such as lying on their back, side, and stomach—to ensure the medication washes over the entire inner surface of the bladder. Once the dwell time is complete, the patient voids the drug by urinating, often into a special receptacle.
Strict safety precautions are necessary when expelling the drug to protect others from exposure. Patients are often instructed to flush the toilet twice after urinating and to wash their hands and genital area thoroughly. These precautions are typically followed for up to 48 hours after the treatment, as trace amounts of the drug may remain in the urine.
Patient Experience and Side Effects
The insertion of the catheter may cause mild, temporary discomfort or a burning sensation as it passes through the urethra. During the dwell time, patients may experience a cool sensation as the liquid is instilled, along with bladder pressure or an increased urge to urinate. Treatment is generally performed in an outpatient setting, allowing the patient to return home shortly after the procedure.
The most common side effects are localized to the bladder, reflecting a temporary chemical irritation known as cystitis. These symptoms include increased urinary frequency, urgency, and discomfort or a burning sensation during urination, known as dysuria. Patients may also notice a small amount of blood or tissue fragments in their urine, which are typically fragments of the shedding bladder lining.
These localized side effects are mild and transient for most patients, usually resolving within 24 to 48 hours. Since the drug is not widely absorbed, patients rarely experience systemic effects like hair loss or severe nausea. However, patients should contact their healthcare provider if they develop a fever, severe abdominal pain, or symptoms that persist beyond a few days, as this could indicate an infection or complication.