Each year, more than 80,000 Americans are diagnosed with bladder cancer. Anyone can get bladder cancer, but factors such as age, race and gender may increase the risk of the disease. Knowing behavior-related risk factors for bladder cancer may help you take preventive measures to reduce your chances of developing the disease or may help you and your doctor detect signs of bladder cancer earlier.
Bladder cancer forms when the DNA in cells in the bladder mutate or change, disabling the functions that control cell growth. In many cases, these mutated cells die or are attacked by the immune system. But some mutated cells may escape the immune system and grow out of control, forming a tumor in the bladder.
While the exact cause of bladder cancer is not known, certain risk factors are linked to the disease, including tobacco smoking and exposure to certain chemicals and gases. Also, people with a family history of bladder cancer have a high risk of developing the disease.
Known risk factors for bladder cancer include:
Gender: Men are at a higher risk than women of getting bladder cancer. According to the American Cancer Society, men have an approximately 1 in 26 chance of developing bladder cancer in their lifetime. For women, this chance is about 1 in 86.
Age: Most people who get bladder cancer are older in age. The average age at diagnosis is 73, and 90 percent of patients are over age 55.
Race: Bladder cancer is twice as common among Caucasians as African Americans. This disease is less common among Hispanics, Asians and Native Americans.
Family history: Individuals with a family member who has or has had bladder cancer are at an increased risk for developing this disease. Sometimes, family members with bladder cancer have been exposed to the same carcinogen. Other times, they may all have certain genetic abnormalities associated with bladder cancer. Specifically, mutations in genes known as GNT and NAT may trigger changes in the body’s breakdown of some toxins, which may in turn cause cancer cells to form in the bladder wall.
Other inherited genetic syndromes are also considered bladder cancer risk factors, such as:
Rb1: An altered form of Rb1, retinoblastoma gene, is associated with cancer of the eye in infants, and may increase your bladder cancer risks.
Lynch syndrome: This genetic condition, also known as hereditary non-polyposis colorectal cancer, is usually tied to colon and endometrial cancer. However, this syndrome may also increase the risk of bladder cancer and cancer of the ureter.
Smoking: Cigarette smoking is the single greatest risk factor for bladder cancer. Smokers are more than twice as likely to get bladder cancer compared to nonsmokers. Inhalation during cigarette smoking brings some of the cancer-causing chemicals in cigarettes out of the lungs and into the blood. These carcinogens are then filtered by the kidneys and deposited into the urine. As urine is held in the bladder, the carcinogens in the fluid may damage the cells on the bladder wall, increasing the risk of cancer.
Workplace exposure: Some chemicals used in the dye industry, such as benzidine and beta-naphthylamine, have been associated with bladder cancer. Other industries where chemicals are used that may cause bladder cancer include rubber, leather, textiles, paint manufacturing and printing. People with jobs that may raise the risk of bladder cancer include painters, machinists, printers, hairdressers (due to hair dye exposure) and truck drivers (due to diesel fume exposure).
Arsenic: Drinking water that contains arsenic has been linked to bladder cancer. Exposure depends on where a person lives and the water source. In the United States, safety measures have been put in place to limit the level of arsenic in public drinking water.
Low fluid consumption: Drinking plenty of fluids daily helps lower your bladder cancer risks. Likewise, not drinking enough may increase this risk because chemicals are left in the bladder longer.
Chronic bladder infections and irritation: Problems associated with increased bladder cancer risks include urinary infections, kidney and bladder stones, and other causes of bladder irritation. Schistosomiasis, a parasitic infection, may reach the bladder and is associated with an increased risk of squamous cell bladder cancer. In the United States, schistosomiasis is very rare. In Africa and the Middle East, where this parasite is more common, squamous cell bladder cancer is more common.
Personal history of bladder cancer: Cancer can occur in other regions of the urothelium, such as in the lining of the kidneys, ureter and urethra. Cancer in any of these areas may increase the risk of another tumor in this layer of cells. People who have bladder cancer need to be closely monitored following treatment because additional tumors in the urothelium are so common.
Bladder defects from birth: Normally, the connection between the belly button and the bladder that forms before we are born disappears before birth. Sometimes, part of this connection remains after birth, and may become cancerous. In another birth defect, the bladder and abdominal wall become fused together, leaving the inner lining of the bladder exposed to other areas of the body. Even following corrective surgery, people who have or had this condition are at a higher risk for bladder cancer.
Chemotherapy and radiation therapy: Long-term use of the chemotherapy drug cyclophosphamide is associated with an increased risk of bladder cancer. Drinking extra fluids while taking this drug can help lower this risk. Radiation aimed at the pelvis is also considered a risk factor for bladder cancer.