An Introduction to Bladder Cancer Treatment
The treatment strategy for bladder cancer is critically dependent on the stage of the disease, specifically the depth to which the tumor has penetrated the bladder wall. A treatment plan is developed after a thorough evaluation that includes the tumor’s stage and grade (how aggressive the cells appear), its size and location, and the patient’s overall health and kidney function.
The most important distinction in bladder cancer is whether it is “non-muscle invasive” or “muscle-invasive.” This single factor dictates the entire treatment pathway and the overall goals of therapy. For non-muscle invasive disease, the goal is to remove the tumors and prevent them from recurring or progressing. For muscle-invasive and more advanced disease, the goals are curative with aggressive therapy or, if the cancer has spread widely, palliative, aiming to control the cancer’s growth and manage symptoms.
The Role of the Multidisciplinary Team
The management of bladder cancer, especially muscle-invasive and advanced disease, requires the coordinated expertise of a multidisciplinary team (MDT). This collaborative approach ensures that all aspects of the patient’s condition are considered, leading to a comprehensive treatment plan.
The core members of a bladder cancer MDT typically include:
- Urologist or Urologic Oncologist: A surgeon who specializes in the urinary system and is the primary physician for diagnosing, staging, and treating bladder cancer, especially with surgical procedures like TURBT and cystectomy.
- Medical Oncologist: A physician who manages systemic therapies, including chemotherapy and immunotherapy, which are essential for muscle-invasive and metastatic disease.
- Radiation Oncologist: A specialist who plans and delivers radiation therapy, a key component of bladder-preserving treatments.
- Pathologist: A physician who examines the tumor tissue removed during biopsy or surgery to determine its type, grade, and depth of invasion.
- Radiologist: A physician who interprets imaging studies, such as CT and MRI scans, to help determine the cancer’s stage.
Understanding Non-Muscle Invasive vs. Muscle-Invasive Disease
The bladder wall has several layers. The innermost layer is the urothelium, and beneath it is a layer of connective tissue, followed by a thick layer of muscle.
- Non-Muscle Invasive Bladder Cancer (NMIBC): This is the most common form, accounting for about 75% of new diagnoses. In NMIBC, the cancer is confined to the inner lining of the bladder (the urothelium) and has not grown into the deeper muscle layer. Treatment focuses on removing the tumors from within the bladder and preventing recurrence.
- Muscle-Invasive Bladder Cancer (MIBC): This occurs when the cancer has grown into the muscle layer of the bladder wall. It is a more serious and aggressive form of the disease because it has a high potential to spread to other parts of the body. Treatment is much more intensive and aims to remove or destroy the entire bladder.
Treatment for Non-Muscle Invasive Bladder Cancer (NMIBC)
The treatment for NMIBC is focused on eradicating existing tumors and reducing the high rate of recurrence.
Transurethral Resection of Bladder Tumor (TURBT)
A TURBT is the first and most important procedure for anyone with a suspected bladder tumor. Performed by a urologist, a thin, rigid instrument called a resectoscope is passed through the urethra into the bladder. The surgeon uses a wire loop at the end of the scope to cut away the tumor and a sample of the underlying muscle. This procedure is crucial for both diagnosis and treatment. It removes the visible tumor and provides the pathologist with the necessary tissue to determine the cancer’s type, grade, and, most importantly, whether it is non-muscle invasive or muscle-invasive.
Intravesical Therapy
Following a TURBT, further treatment is often needed to reduce the risk of the cancer returning. This involves administering medication directly into the bladder through a temporary catheter. This is called intravesical therapy.
- Intravesical Chemotherapy: A single dose of liquid chemotherapy is often given inside the bladder within 24 hours of the TURBT. This is done to kill any floating cancer cells that may have been dislodged during the resection, reducing the chance that they will implant elsewhere in the bladder.
- Intravesical Immunotherapy with BCG (Bacillus Calmette-Guérin): For patients with higher-risk NMIBC (tumors that are larger, higher grade, or recurrent), a course of intravesical immunotherapy with BCG is the standard of care. BCG is a weakened, live bacterium that was originally developed as a vaccine for tuberculosis. When instilled in the bladder, it stimulates a powerful local immune response that attacks and destroys any remaining bladder cancer cells. Treatment typically involves a six-week induction course followed by a longer-term maintenance schedule.
Treatment for Muscle-Invasive Bladder Cancer (MIBC)
When cancer invades the muscle wall, it requires a much more aggressive, multi-modal treatment approach with curative intent.
Neoadjuvant Chemotherapy
For patients with MIBC who are candidates for surgery, the current standard of care is to give several cycles of systemic, platinum-based chemotherapy before the surgery. This is called neoadjuvant chemotherapy. It has two main benefits: it can shrink the tumor in the bladder, and more importantly, it treats any microscopic cancer cells (micrometastases) that may have already escaped the bladder but are too small to see on scans.
Radical Cystectomy and Urinary Diversion
A radical cystectomy is the definitive surgical treatment for MIBC. This is a major operation that involves the complete removal of the bladder and nearby lymph nodes. In men, the prostate and seminal vesicles are also removed. In women, the uterus, cervix, ovaries, and part of the vagina are typically removed.
Because the bladder is removed, the surgeon must create a new way for urine to exit the body. This is called a urinary diversion. The two most common types are:
- Ileal Conduit: The surgeon takes a short piece of the small intestine (the ileum), closes one end, and attaches the ureters (the tubes from the kidneys) to it. The other end is brought out through the abdominal wall to create a stoma. Urine continuously drains from the kidneys, through the conduit, and out the stoma into a small bag (an ostomy pouch) that is worn on the outside of the body.
- Neobladder: The surgeon creates a new, sphere-shaped bladder out of a longer piece of small intestine. The ureters are attached to this new bladder, which is then connected to the urethra. This allows the patient to urinate through the urethra, avoiding the need for an external bag.
Bladder-Preserving Therapy (Trimodal Therapy)
For a select group of patients with MIBC who are unwilling or unable to undergo a radical cystectomy, a bladder-preserving approach called trimodal therapy may be an option. This intensive treatment combines three modalities: a maximally safe TURBT to remove as much tumor as possible, followed by a course of radiation therapy to the pelvis combined with concurrent radiosensitizing chemotherapy.
Treatment for Metastatic Bladder Cancer
If bladder cancer spreads to distant organs like the lungs, liver, or bones, it is considered metastatic and is not curable. Treatment focuses on controlling the disease with systemic medications.
- Systemic Chemotherapy: Platinum-based chemotherapy has long been the foundation of treatment for metastatic bladder cancer.
- Immunotherapy: Immune checkpoint inhibitors have revolutionized the treatment of advanced bladder cancer. These drugs “unleash” the body’s own immune system to fight the cancer and have become a standard of care, either as an initial treatment in combination with chemotherapy or as a “switch maintenance” therapy for patients whose cancer has not progressed after initial chemotherapy.
Frequently Asked Questions
1. What is the most important factor in deciding bladder cancer treatment?
The most critical factor is the stage of the cancer, specifically its depth of invasion. The distinction between non-muscle invasive bladder cancer (NMIBC), which is confined to the bladder lining, and muscle-invasive bladder cancer (MIBC), which has grown into the muscle wall, determines the entire treatment pathway.
2. What is a TURBT and why is it performed?
A TURBT (Transurethral Resection of Bladder Tumor) is a procedure where a surgeon passes an instrument through the urethra to cut away a tumor from the bladder lining. It is essential for both diagnosis and treatment. It removes the visible tumor and provides tissue for the pathologist to determine the cancer’s type, grade, and depth, thereby establishing whether it is NMIBC or MIBC.
3. How does BCG work for bladder cancer?
BCG (Bacillus Calmette-Guérin) is a type of intravesical immunotherapy. It is a weakened bacterium that, when placed into the bladder, provokes a strong, localized immune response. The body’s own immune cells are drawn to the bladder lining, where they attack and destroy any remaining cancer cells, reducing the risk of recurrence.
4. Why is chemotherapy often given before bladder removal surgery?
Chemotherapy given before a radical cystectomy is called neoadjuvant chemotherapy. Its primary purpose is to treat any microscopic cancer cells that may have already spread outside the bladder but are too small to be seen on scans. This has been shown to improve long-term survival rates. It can also help shrink the tumor in the bladder itself.
5. What happens to urine after a radical cystectomy?
After the bladder is removed, the surgeon must create a new path for urine to leave the body, called a urinary diversion. The most common method is an ileal conduit, where urine drains through a stoma on the abdomen into an external pouch. Another option is a neobladder, where a new bladder is constructed from intestine and connected to the urethra, allowing for urination without an external bag.
6. Is it possible to treat muscle-invasive bladder cancer without removing the bladder?
Yes, in some select cases. An approach called trimodal therapy offers a bladder-preserving option. It involves a combination of a thorough surgical resection of the tumor via TURBT, followed by a course of radiation therapy combined with chemotherapy. This is an intensive treatment and is only suitable for certain patients.
7. How has immunotherapy changed the treatment of advanced bladder cancer?
Immunotherapy with drugs known as checkpoint inhibitors has become a cornerstone of treatment for advanced or metastatic bladder cancer. These drugs help the body’s own immune system to recognize and attack cancer cells. They have shown significant benefit and are now used as a standard part of treatment, often in combination with or following chemotherapy.
