Bladder Cancer

Bladder Cancer: 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.

Estimated new cases and deaths from bladder cancer in the United States in 2009:
 
  New cases: 70,980
 
 
  Deaths: 14,330
 

Incidence & Mortality

 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.

There are three types of bladder cancer that begin in cells in the lining of the bladder. These cancers are named for the type of cells that become malignant:

Transitional cell carcinoma: Cancer that begins in cells in the innermost tissue layer of the bladder. These cells are able to stretch when the bladder is full and shrink when it is emptied. Most bladder cancers begin in transitional cells.

Squamous cell carcinoma: Cancer that begins in squamous cells, which are thin, flat cells that may form in the bladder after a long- term infection or irritation.

Adenocarcinoma: Cancer that begins in glandular (secretory) cells that may form in the bladder after a long-term inflammation or irritation.
Cancer that is only in cells in the lining of the bladder is called superficial bladder cancer. The doctor might call it carcinoma in situ. This type of bladder cancer often comes back after treatment. If this happens, the disease most often recurs as another superficial cancer in the bladder.

Cancer that begins as a superficial tumor may grow through the lining and into the muscular wall of the bladder. This is known as invasive cancer. Invasive cancer may extend through the bladder wall. It may grow into a nearby organ such as the uterus or vagina (in women) or the prostate gland (in men). It also may invade the wall of the abdomen.

When bladder cancer spreads outside the bladder, cancer cells are often found in nearby lymph nodes. If the cancer has reached these nodes, cancer cells may have spread to other lymph nodes or other organs, such as the lungs, liver, or bones.

When cancer spreads (metastasizes) from its original place to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the primary tumor. For example, if bladder cancer spreads to the lungs, the cancer cells in the lungs are actually bladder cancer cells. The disease is metastatic bladder cancer, not lung cancer. It is treated as bladder cancer, not as lung cancer. Doctors sometimes call the new tumor "distant" disease.

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.

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.

 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.

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.

 Statistics

From 2002-2006, the median age at diagnosis for cancer of the urinary bladder was 73 years of age3X Close. Approximately 0.1% were diagnosed under age 20; 0.5% between 20 and 34; 2.0% between 35 and 44; 7.5% between 45 and 54; 17.8% between 55 and 64; 27.5% between 65 and 74; 32.1% between 75 and 84; and 12.5% 85+ years of age.

The age-adjusted incidence rate was 21.0 per 100,000 men and women per year. These rates are based on cases diagnosed in 2002-2006 from 17 SEER geographic areas.

US Mortality

From 2002-2006, the median age at death for cancer of the urinary bladder was 78 years of age. Approximately 0.0% died under age 20; 0.1% between 20 and 34; 0.9% between 35 and 44; 4.0% between 45 and 54; 11.1% between 55 and 64; 21.5% between 65 and 74; 36.9% between 75 and 84; and 25.4% 85+ years of age.

The age-adjusted death rate was 4.3 per 100,000 men and women per year. These rates are based on patients who died in 2002-2006 in the US.

Trends in Rates

 Information for trends over a fixed period of time.
The average annual percent change over several years.

A statistical model for characterizing cancer trends which uses statistical criteria to determine how many times and when the trends in incidence or mortality rates have changed.

Survival & Stage

A measure of net survival that is calculated by comparing observed (overall) survival with expected survival from a comparable set of people that do not have cancer to measure the excess mortality that is associated with a cancer diagnosis., which measures the survival of the cancer patients in comparison to the general population to estimate the effect of cancer. The overall 5-year relative survival rate for 1999-2005 from 17 SEER geographic areas was 80.0%. Five-year relative survival rates by race and sex were: 81.7% for white men; 77.0% for white women; 71.5% for black men; 57.3% for black women.

Lifetime Risk

Based on rates from 2004-2006, 2.41% of men and women born today will be diagnosed with cancer of the urinary bladder at some time during their lifetime. This number can also be expressed as 1 in 41 men and women will be diagnosed with cancer of the urinary bladder during their lifetime. These statistics are called the lifetime risk.
The probability of developing cancer in the course of one's lifespan. Lifetime risk may also be discussed in terms of the probability of developing or of dying from cancer. Based on cancer rates from 2004 to 2006, it was estimated that men had about a 44 percent chance of developing cancer in their lifetimes, while women had about a 38 percent chance. of developing cancer.
The chance that a person will develop cancer in his/her lifetime. cancer of the urinary bladder between two age groups. For example, 1.19% of men will develop cancer of the urinary bladder between their 50th and 70th birthdays compared to 0.34% for women.

Prevalence

On January 1, 2006, in the United States there were approximately 527,496 men and women alive who had a history of cancer of the urinary bladder -- 388,965 men and 138,531 women. This includes any person alive on January 1, 2006 who had been diagnosed with cancer of the urinary bladder at any point prior to January 1, 2006 and includes persons with active disease and those who are cured of their disease.

The average annual percent change over several years. The APC is used to measure trends or the change in rates over time.

Joinpoint analyses

A statistical model for characterizing cancer trends which uses statistical criteria to determine how many times and when the trends in incidence or mortality rates have changed. The results of joinpoint are given as calendar year ranges, and the annual percent change (APC) in the rates over each period.

Survival rates

Survival examines how long after diagnosis people live. Cancer survival is measured in a number of different ways depending on the intended purpose.

Relative survival rate

A measure of net survival that is calculated by comparing observed (overall) survival with expected survival from a comparable set of people that do not have cancer to measure the excess mortality that is associated with a cancer diagnosis.

Stage distribution

Stage provides a measure of disease progression, detailing the degree to which the cancer has advanced. Two methods commonly used to determine stage are AJCC and SEER Summary Stage. The AJCC method (see Collaborative Staging Method) is more commonly used in the clinical settings, while SEER has strived to provide consistent definitions over time with their Local/Regional/Distant staging.

Lifetime risk

The probability of developing cancer in the course of one's lifespan. Lifetime risk may also be discussed in terms of the probability of developing or of dying from cancer. Based on cancer rates from 2004 to 2006, it was estimated that men had about a 44 percent chance of developing cancer in their lifetimes, while women had about a 38 percent chance.

Probability of developing cancer

The chance that a person will develop cancer in his/her lifetime.

Prevalence

The number of people who have received a diagnosis of cancer during a defined time period, and who are alive on the last day of that period. Most prevalence data in SEER is for limited duration because information on cases diagnosed before 1973 is not generally available.

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References
All statistics in this report are based on SEER incidence and NCHS mortality statistics.

Source: NCI (National Cancer Institute)