General Information About Bladder and Other Urothelial Cancers
Key Points for This Section
Bladder and other urothelial cancers are diseases in which malignant (cancer) cells form in the urothelium.
The bladder is a hollow organ in the lower part of the abdomen. It is shaped like a small balloon and has a muscle wall that allows it to get larger or smaller. The bladder holds urine until it is passed out of the body. Urine is the liquid waste that is made by the kidneys as they clean the blood. The urine passes from the two kidneys into the bladder through two tubes called ureters. When the bladder is emptied during urination, the urine goes from the bladder to the outside of the body through another tube called the urethra.
The urothelium is a layer of tissue that lines the urethra, bladder, ureters, prostate, and renal pelvis. Cancer that begins in the urothelium of the bladder is much more common than cancer that begins in the urothelium of the urethra, ureters, prostate, or renal pelvis. Because it is the most common form of urothelial cancer, bladder cancer is the focus of this summary.
- Transitional cell carcinoma: Cancer that begins in cells in the innermost layer of the bladder urothelium. These cells are able to stretch when the bladder is full and shrink when it is emptied. Most bladder cancers begin in the transitional cells.
- Squamous cell carcinoma: Cancer that forms in squamous cells, which are thin, flat cells that may form in the bladder urothelium after long-term infection or irritation.
- Adenocarcinoma: Cancer that begins in glandular (secretory) cells. Glandular cells in the bladder urothelium make substances such as mucus.
See the following PDQ summaries for more information about bladder and other urothelial cancers:
The risk of bladder cancer increases with age.
In the United States, bladder cancer occurs more often in men than in women, and more often in whites than in blacks. As the U.S. population has gotten older, the number of people diagnosed with bladder cancer has increased, but the number of deaths from bladder cancer has decreased. This is true for men and women of all races over the last 30 years.
Smoking can affect the risk of bladder cancer.
Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk to your doctor if you think you may be at risk for bladder cancer. Risk factors for bladder cancer include:
- Using tobacco, especially smoking cigarettes.
- Having a family history of bladder cancer.
- Having certain changes in the genes.
- Being exposed to paints, dyes, metals or petroleum products in the workplace.
- Past treatment with radiation therapy to the pelvis or with certain anticancer drugs, such as cyclophosphamide or ifosfamide.
- Taking Aristolochia fangchi, a Chinese herb.
- Drinking well water that has high levels of arsenic.
- Drinking water that has been treated with chlorine.
- Having a history of bladder infections, including bladder infections caused by Schistosoma haematobium.
- Using urinary catheters for a long time.