Overview of Bladder Cancer
The bladder is a hollow and muscular organ that sits low in the abdomen, near the pelvis. It can expand and stretch to accommodate waste in the form of urine. Tubes called the ureters transfer urine from the kidneys into the bladder for storage. When the bladder is full, the muscles in the organ contract and expel urine out of the bladder, through a tube called the urethra, and out of the body.
Typically, cancers begin when cells begin to divide and grow uncontrollably. Bladder cancer generally follows the same pattern. Cells in the lining of the bladder begin to grow out of control and can form a tumor. If not caught and treated early, this growth can continue and spread to other parts of the body. The National Cancer Institute estimates that in 2021, there will be approximately 83,730 new cases of bladder cancer diagnosed in the United States. That number accounts for 4.4 percent of all new cancer cases in the country.
There are several different types of bladder cancer, including:
- Urothelial carcinoma. This is the most common type of bladder cancer. Urothelial carcinoma starts as the uncontrolled growth of the cells that line the inside of the bladder itself. However, urothelial cells which line the bladder are also found in other areas of the body, such as the ureters, urethra, and part of the kidneys. If the cancer is urothelial carcinoma, a physician will typically also check these other areas of the body for the presence of tumors.
- Squamous cell carcinoma. This form of cancer begins in thin, flat cells called squamous cells. Some of these cells can be found in the lining inside the bladder. Squamous cell carcinoma accounts for only one to two percent of all bladder cancer cases in the U.S. However, almost all types of squamous cell carcinomas can be invasive. This type of cancer is more prevalent in patients who suffer long-term infections, inflammation, or irritation of the bladder.
- Adenocarcinoma. This form of bladder cancer is also fairly rare and begins in the cells that make up the mucus-secreting glands in the bladder. This form of cancer tends to be on the invasive side.
- Small cell carcinoma. This is among the rarest forms of bladder cancer. The disease begins in cells called neuroendocrine cells, which are nerve-like cells. This type of cancer can grow rapidly.
- Sarcoma. This type of bladder cancer begins in the muscle cells of the bladder and is on the rare side of the bladder cancer spectrum.
When describing bladder cancer, physicians may use terms like invasive and non-invasive to describe a person’s condition. “Invasive” means that the cancer has grown into the deeper layers of the bladder wall. Invasive cancers can be harder to treat and are generally more likely to spread to other parts of the body. “Non-invasive” typically means that the cancer has only impacted the inner layer of cells of the bladder and has not reached deeper layers of the organ.
Symptoms of Bladder Cancer
One of the most common symptoms of bladder cancer is blood in the urine. When the urine suddenly changes colors, this symptom may be so alarming that people rush to their physician right away. Talking to a physician at the first sign of abnormal urination can be the key to the early detection of bladder cancer. Spotting the potential warning signs of cancer early typically gives people a better chance at beating the disease. Other symptoms of bladder cancer can include:
- Blood in the urine
- Urine that is orange, pink, or dark red
- Urinating more frequently than normal
- Painful urination
- Burning sensation while urinating
- Trouble urinating
- Inability to urinate
- Lower back pain
Many of these symptoms may seem general in nature or point toward bladder infections, urinary tract issues, or prostate problems. However, if you are experiencing any of these symptoms, it is important to talk to your doctor to narrow down the cause.
Bladder Cancer Causes
The development of bladder cancer has been linked to both genetics and environmental exposure. Some bladder cancers, according to the American Cancer Society, are caused by genetics. Individuals may inherit some gene abnormalities, which may increase their risk of developing the disease, although bladder cancer does not commonly run in families.
Bladder cancer is more commonly caused by acquired gene mutations rather than inherited ones. In essence, these gene mutations are the result of exposure to certain environmental factors. The TP53 and RB1 tumor suppressor genes and FGFR and RAS oncogenes are thought to be the genes most likely involved in the development of bladder cancers. Things that can impact these genes and cause mutations include exposure to certain chemicals, especially those found in tobacco smoke. Exposure to some paints, dyes, metals, and petroleum products may also lead to the formation of bladder cancer.
Bladder cancer may also be the result of chronic bladder irritation from the use of catheters. It may also develop in those who have a history of bladder infections and chronic bladder inflammation.
Risk Factors for Developing Bladder Cancer
There are several different risk factors for developing bladder cancer. These causes can range from genetic factors to health and lifestyle choices and even workplace exposure to certain chemicals. Some of the risk factors for bladder cancer tend to involve:
- Increasing age
- Being male
- Smoking
- Exposure to certain chemicals
- Exposure to arsenic
- Taking certain herbal supplements with aristolochic acid or Aristolochia fangchi
- Taking certain pharmaceuticals such as pioglitazone
- Taking the chemotherapy drug cyclophosphamide
- Not drinking enough fluids
- Having chronic bladder infections
- Family history of bladder cancer
- Certain bladder birth defects
Survival Rates
Surviving a bladder cancer diagnosis depends on a variety of factors, including how early the cancer was caught and whether it has had a chance to spread to other areas of the body. In general, according to statistics from the National Cancer Institute, about 77 percent of people diagnosed with bladder cancer will survive for five years or more.