Skip Navigation

Bladder Cancer

Last Updated: Mar 1, 2019


Bladder cancer is a cancer that occurs in the bladder - the balloon-shaped organ that collects urine until it is excreted. It is caused by an uncontrolled growth of cells that form lumps called tumors. While some tumors are harmless, others continue to grow and eventually invade other organs. Bladder cancer is characterized by its location and growth through the four layers of the bladder wall. These include:

picture of urinary bladder along with ureters and prostate

The most common type of bladder cancer is transitional cell (urothelial) carcinoma, which accounts for 90% of diagnosed cases. The affected cells resemble the urothelium cells of the inner bladder lining. Since urothelium cells also line other organs in the urinary tract, this type of cancer may also be found in the kidneys, ureters and urethra.

There are two subtypes of urothelial carcinomas, based on how the cells grow; papillary carcinomas form finger-like projections toward the inner hollow cavity of the bladder, while flat carcinomas do not form projections. Cancers are also classified as invasive or non-invasive based on the extent of growth through the bladder lining. Non-invasive tumors stay confined to the urothelium, while invasive tumors infiltrate the lamina propria and beyond - these cancers are more challenging to treat.

Other bladder cancers are squamous cell carcinoma, adenocarcinoma, small cell carcinoma and sarcoma. These cancers are much less common and each make up ~1% or less of all bladder cancers. Bladder cancer is often diagnosed early with good outcomes for patients. However, due to its high recurrence rate, continued monitoring is necessary.

Causes and Risk Factors

The cell cycle has built-in checks and balances that prevent uncontrolled cell division. When these checkpoints fail - as a result of mutations in the genetic code of key genes - cells grow into tumors. The molecular details of how cancer begins are not fully understood, but the known risk factors include:


The symptoms of bladder cancer include:

Symptoms of advanced bladder cancer are:

Diagnosis and Treatment

The following tests are used to diagnose bladder cancer:

Imaging tests are used to “stage” the cancer and determine the extent to which it has spread to other organs. Bladder cancer is staged from 1-4 (represented as Roman numerals I-IV).

Treatment options vary depending on the stage of the bladder cancer and the health of the patient. In most cases, bladder cancer is caught early and is fully treatable. Treatment options for bladder cancer include:


Bladder cancer is caused by random molecular events that cannot be prevented. The best way to reduce the risk of developing bladder cancer is by eating a healthy diet, drinking plenty of fluids, avoiding hazardous chemicals and not smoking. Those with a family or personal history of urinary tract cancers can discuss screening options with their physician.


Additional Resources

Home Health Testing Guides

Testing Company Reviews

Related Topics

Tina Shahian, PhD

Tina is a writer for Innerbody Research, where she has written a large body of informative guides about health conditions.


A communication specialist in life science and biotech subjects, Tina’s successful career is rooted in her ability to convey complex scientific topics to diverse audiences. Tina earned her PhD in Biochemistry from the University of California, San Francisco and her BS degree in Cell Biology from U.C. Davis. Tina Shahian’s Linkedin profile.


In her spare time, Tina enjoys drawing science-related cartoons.