Worlds of David Darling
Encyclopedia of Science
   
Home > Encyclopedia of Science

bladder cancer





Contents

  • The bladder
  • Who is at risk of bladder cancer?
  • Signs and symptoms
  • Diagnosis of bladder cancer
  • Staging the disease
  • Treatment of bladder cancer
  • female urinary tract
    male urinary tract
    Cancer that forms in tissues of the bladder (the organ that stores urine). Most bladder cancers are transitional cell carcinomas (cancer that begins in cells that normally make up the inner lining of the bladder). Other types include squamous cell carcinoma (cancer that begins in thin, flat cells) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids). The cells that form squamous cell carcinoma and adenocarcinoma develop in the inner lining of the bladder as a result of chronic irritation and inflammation.


    The bladder

    The bladder is a hollow organ in the lower abdomen. It stores urine, the liquid waste produced by the kidneys. Urine passes from each kidney into the bladder through a tube called a ureter.

    An outer layer of muscle surrounds the inner lining of the bladder. When the bladder is full, the muscles in the bladder wall can tighten to allow urination. Urine leaves the bladder through another tube, the urethra.


    Who is at risk from bladder cancer?


    No one knows the exact causes of bladder cancer. However, it is clear that this disease is not contagious. No one can "catch" cancer from another person.

    People who get bladder cancer are more likely than other people to have certain risk factors. A risk factor is something that increases a person's chance of developing the disease.

    Still, most people with known risk factors do not get bladder cancer, and many who do get this disease have none of these factors. Doctors can seldom explain why one person gets this cancer and another does not.

    Studies have found the following risk factors for bladder cancer:
    • Age. The chance of getting bladder cancer goes up as people get older. People under 40 rarely get this disease.


    • Tobacco. The use of tobacco is a major risk factor. Cigarette smokers are two to three times more likely than nonsmokers to get bladder cancer. Pipe and cigar smokers are also at increased risk.


    • Occupation. Some workers have a higher risk of getting bladder cancer because of carcinogens in the workplace. Workers in the rubber, chemical, and leather industries are at risk. So are hairdressers, machinists, metal workers, printers, painters, textile workers, and truck drivers.


    • Infections. Being infected with certain parasites increases the risk of bladder cancer. These parasites are common in tropical areas but not in the United States.


    • Treatment with cyclophosphamide or arsenic. These drugs are used to treat cancer and some other conditions. They raise the risk of bladder cancer.


    • Race. Whites get bladder cancer twice as often as African Americans and Hispanics. The lowest rates are among Asians.


    • Being a man. Men are two to three times more likely than women to get bladder cancer.


    • Family history. People with family members who have bladder cancer are more likely to get the disease. Researchers are studying changes in certain genes that may increase the risk of bladder cancer.


    • Personal history of bladder cancer. People who have had bladder cancer have an increased chance of getting the disease again.

    Chlorine is added to water to make it safe to drink. It kills deadly bacteria. However, chlorine by-products sometimes can form in chlorinated water. Researchers have been studying chlorine by-products for more than 25 years. So far, there is no proof that chlorinated water causes bladder cancer in people. Studies continue to look at this question.

    Some studies have found that saccharin, an artificial sweetener, causes bladder cancer in animals. However, research does not show that saccharin causes cancer in people.

    People who think they may be at risk for bladder cancer should discuss this concern with their doctor. The doctor may suggest ways to reduce the risk and can plan an appropriate schedule for checkups.





    What are the signs and symptoms of bladder cancer?

    Common symptoms of bladder cancer include:
    • Blood in the urine (making the urine slightly rusty to deep red),
    • Pain during urination, and
    • Frequent urination, or feeling the need to urinate without results.
    These symptoms are not sure signs of bladder cancer. Infections, benign tumors, bladder stones, or other problems also can cause these symptoms. Anyone with these symptoms should see a doctor so that the doctor can diagnose and treat any problem as early as possible. People with symptoms like these may see their family doctor or a urologist, a doctor who specializes in diseases of the urinary system.


    How is bladder cancer diagnosed?

    If a patient has symptoms that suggest bladder cancer, the doctor may check general signs of health and may order lab tests. The person may have one or more of the following procedures:
    • Physical exam. The doctor feels the abdomen and pelvis for tumors. The physical exam may include a rectal or vaginal exam.


    • Urine tests. The laboratory checks the urine for blood, cancer cells, and other signs of disease.


    • Intravenous pyelogram. The doctor injects dye into a blood vessel. The dye collects in the urine, making the bladder show up on X-rays.


    • Cystoscopy. The doctor uses a thin, lighted tube (cystoscope) to look directly into the bladder. The doctor inserts the cystoscope into the bladder through the urethra to examine the lining of the bladder. The patient may need anesthesia for this procedure.
    The doctor can remove samples of tissue with the cystoscope. A pathologist then examines the tissue under a microscope. The removal of tissue to look for cancer cells is called a biopsy. In many cases, a biopsy is the only sure way to tell whether cancer is present. For a small number of patients, the doctor removes the entire cancerous area during the biopsy. For these patients, bladder cancer is diagnosed and treated in a single procedure.

    A patient who needs a biopsy may want to ask the doctor some of the following questions:
    • Why do I need to have a biopsy?
    • How long will it take? Will I be awake? Will it hurt?
    • How soon will I know the results?
    • Are there any risks? What are the chances of infection or bleeding after the biopsy?
    • If I do have cancer, who will talk with me about treatment? When?

    Staging the disease

    If bladder cancer is diagnosed, the doctor needs to know the stage, or extent, of the disease to plan the best treatment. Staging is a careful attempt to find out whether the cancer has invaded the bladder wall, whether the disease has spread, and if so, to what parts of the body.

    The doctor may determine the stage of bladder cancer at the time of diagnosis, or may need to give the patient more tests. Such tests may include imaging tests – CT scan, magnetic resonance imaging (MRI), sonogram, intravenous pyelogram, bone scan, or chest X-ray. Sometimes staging is not complete until the patient has surgery.

    These are the main features of each stage of the disease:
    • Stage 0. The cancer cells are found only on the surface of the inner lining of the bladder. The doctor may call this superficial cancer or carcinoma in situ.


    • Stage I. The cancer cells are found deep in the inner lining of the bladder. They have not spread to the muscle of the bladder.


    • Stage II. The cancer cells have spread to the muscle of the bladder.


    • Stage III. The cancer cells have spread through the muscular wall of the bladder to the layer of tissue surrounding the bladder. The cancer cells may have spread to the prostate (in men) or to the uterus or vagina (in women).


    • Stage IV. The cancer extends to the wall of the abdomen or to the wall of the pelvis. The cancer cells may have spread to lymph nodes and other parts of the body far away from the bladder, such as the lungs.

    How is bladder cancer treated?

    Read about how bladder cancer is treated.


    Related category

       • HEALTH AND DISEASE

    Source: National Cancer Institute