What Is Bladder Cancer?
Bladder cancer is the growth of malignant cells in the lining of the bladder. Often, more than one tumor is present at a time, and the cancer may spread into and through the wall of the bladder. The most frequent symptom of bladder cancer is painless hematuria (blood in the urine), although commonly there are no symptoms at all. Therefore, when symptoms of a bladder disorder do arise, they are most often due to other, less serious, conditions such as infections, benign prostate enlargement, or bladder stones. Bladder cancer is rare before the age of 40 and is more common among men.
Superficial tumors affect only the bladder lining. They grow up and out from the lining tissue and extend into the bladder's hollow cavity. Invasive tumors grow down into the deeper layers of bladder tissue, and they may involve surrounding muscle, fat, and/or nearby organs. Invasive tumors are more dangerous than superficial tumors, since they are more likely to metastasize (spread).
Superficial bladder cancer has a 5-year survival rate of about 85%. Invasive bladder cancer has a less favorable prognosis: Approximately 5% of patients with metastasized bladder cancer live 2 years after diagnosis. Cases of recurrent bladder cancer indicate an aggressive tumor and a poor prognosis.
Who Gets Bladder Cancer?
According to the National Cancer Institute, the highest incidence of bladder cancer occurs in industrialized countries such as the United States, Canada, and France. Incidence is lowest in Asia and South America, where it is about 70% lower than in the United States.
Incidence of bladder cancer increases with age. People over the age of 70 develop the disease 2 to 3 times more often than those aged 55–69 and 15 to 20 times more often than those aged 30–54.
Bladder cancer is 2 to 3 times more common in men. In the United States, approximately 38,000 men and 15,000 women are diagnosed with the disease each year. Bladder cancer is the fourth most common type of cancer in men and the eighth most common type in women. The disease is more prevalent in Caucasians than in African Americans and Hispanics.
- Blood in the urine.
- Difficult, frequent, or painful urination.
- Pain in the pelvic region.
- Feeling of pressure in the back.
- Persistent fever.
- Smoking is associated with an increased incidence of bladder cancer.
- Exposure to toxic chemicals (such as those used in the rubber industry as well as industrial dyes and solvents) is a potential risk factor.
- A family history of bladder cancer is associated with an increased risk.
Other bladder cancer risk factors include the following:
- Chronic bladder inflammation (recurrent urinary tract infections, urinary stones).
- Consumption of Aristolochia fangchi (herb used in some weight-loss formulas).
- Diet high in saturated fat.
- Exposure to second-hand smoke.
- External beam radiation.
- Gender (male).
- Infection with Schistosoma haematobium (parasite found in many developing countries).
- Race (Caucasian).
- Treatment with certain drugs (e.g., cyclophosfamide—used to treat cancer).
Workers at increased risk include the following:
- Truck drivers.
- Medical workers who prepare antineoplastic drugs (used in chemotherapy).
- Workers in rubber, chemical, textile, metal, and leather industries.
- Patient history and physical exam help to establish the presence of a bladder disorder.
- Cystoscopy (the use of a thin, lighted tube that allows a surgeon to see the bladder directly) and biopsy (removal and analysis of tissue samples) are required for a definitive diagnosis. If the sample is positive, the cancer is staged using the tumor, node, metastases (TNM) system.
- Urinalysis may be used to detect cancer cells and blood in the urine. NMP22BladderChek is a urine test used to detect elevated levels of a nuclear matrix protein (called NMP22). Bladder cancer increases levels of this protein in the urine, even during early stages of the disease. Studies have shown that when NMP22BladderChek is used with cystoscopy, it may increase the clinical sensitivity of the evaluation, compared to cystoscopy and urinalysis alone.
- CT (computed tomography) scans provide a view of the bladder and surrounding tissues to reveal any structural abnormalities. Other imaging tests include MRI scan, bone scan, and ultrasound.
- There is a strong correlation between tumor stage (depth of penetration) and tumor grade (speed of growth). Nearly all superficial tumors are low grade; that is, they are Grade 1 tumors, with cells that are distinctly specialized and well-differentiated, whereas nearly all muscle-invasive tumors are high grade; that is, they are Grade 3 tumors, with cells that are nonspecialized and poorly differentiated. More importantly, there is a strong correlation between tumor stage and prognosis (the probable outcome of a disease), with superficial tumors having the most chance of a favorable result.
- Tumors in the early stages may be removed surgically through the cystoscope. Such tumors may recur, thus requiring repeated cystoscopy every three months for one to two years, then every six months for one to two more years, and then yearly for life.
- Recurrences may also be treated with chemotherapeutic agents instilled directly into the bladder with a catheter.
- Chemotherapy given intravenously may be used prior to radical surgery to downgrade the stage of tumor or if there is evidence that the cancer has spread.
- If the cancer is advanced, partial or radical removal of the bladder is required (cystectomy). Radiation and chemotherapy may also be used. Until recently, most bladder cancer patients who underwent cystectomy required an ostomy (surgical creation of an artificial opening) and an external bag to collect urine. Newer reconstructive surgical methods that divert the urinary tract include the continent urinary reservoir or the neobladder.
- External beam radiation is emitted from a machine outside the body and internal radiation is emitted from radioactive "seeds" implanted into the tumor. Either type of radiation therapy may be used after surgery to destroy cancer cells that may remain. Radiation therapy is also used to relieve symptoms (called palliative treatment) of advanced bladder.
- Immunotherapy, also called biological therapy, may be used in some cases of superficial bladder cancer. This treatment is used to enhance the immune system's ability to fight disease. A vaccine derived from the bacteria that causes tuberculosis (BCG) is infused through the urethra into the bladder, once a week for 6 weeks to stimulate the immune system to destroy cancer cells. Sometimes BCG is used with interferon.
- Photodynamic therapy is a new treatment for early bladder cancer. It involves administering drugs to make cancer cells more sensitive to light and then shining a special light onto the bladder. This treatment is being studied in clinical trials.
- Chemotherapy can be administered before surgery (neoadjuvant therapy) or after surgery (adjuvant therapy). Drugs commonly used to treat bladder cancer include thiotepa (Thioplex), mitomycin, and doxorubicin (Rubex). Intravesical chemotherapy (e.g., valrubicin [Valstar]) may be used to treat early bladder cancer as an alternative to surgery.
- Don’t smoke cigarettes.
- Exercise caution if you work with industrial dyes or in the rubber industry.
- If you have a family history of the disease, get regular checkups.
- See your doctor regularly if you have had bladder cancer to screen for recurrences.
When To Call Your Doctor
Call a doctor if you have blood in the urine or you experience other symptoms of bladder cancer.
Reviewed by Sovrin M. Shah, M.D., F.A.C.S., Assistant Professor of Urology, Icahn School of Medicine at Mount Sinai, Pelvic Medicine and Reconstructive Surgery, Sol and Margaret Berger Department of Urology, Mount Sinai Beth Israel, and Phillips Ambulatory Care Center, New York, NY. Review provided by VeriMed Healthcare Network.