What is bladder cancer?

Bladder cancer starts in the cells of the bladder. A cancerous (malignant) tumour is a group of cancer cells that can grow into nearby tissue and destroy it. The tumour can also spread (metastasize) to other parts of the body.

The bladder is part of the urinary system. It is a hollow organ in the pelvis that stores urine (pee) (a liquid waste product) before it passes out of the body.

Diagram of the location of the bladder
Diagram of the location of the bladder

Cells in the bladder sometimes change and no longer grow or behave normally. These changes may lead to non-cancerous (benign) tumours such as papillomas. They can also lead to non-cancerous conditions such as urinary tract infections (UTIs).

But in some cases, changes to bladder cells can cause bladder cancer. Most often, bladder cancer starts in urothelial cells that line the inside of the bladder. This type of cancer is called urothelial carcinoma of the bladder (also called transitional cell carcinoma). Urothelial carcinomas make up more than 90% of all bladder cancers. They are often diagnosed at an early stage and have not grown into the deeper muscle layer of the bladder wall.

Rare types of bladder cancer can also develop. These include squamous cell carcinoma and adenocarcinoma of the bladder.

Expert review and references

  • Al-Ahmadie H, Lin O, Reuter VE . Pathology and cytology of tumors of the urinary tract. Scardino PT, Lineham WM, Zelefsky MJ, Vogelzang NJ (eds.). Comprehensive Textbook of Genitourinary Oncology. 4th ed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins; 2011: 16:295-316.
  • American Society of Clinical Oncology . Bladder Cancer . 2017 : https://www.cancer.net/.
  • Feldman AS, Efstathiou JA, Lee RJ, Dahl DM, Michaelson MD, Zietman AL . Cancer of the bladder, ureter, and renal pelvis. DeVita VT Jr, Lawrence TS, Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 65:896-916.
  • Martini FH, Timmons MJ, Tallitsch RB. Human Anatomy. 7th ed. San Francisco: Pearson Benjamin Cummings; 2012.
  • Penn Medicine . All About Bladder Cancer . University of Pennsylvania ; 2017 : https://www.oncolink.org/.

The bladder

The bladder is part of the urinary system. Learn about the bladder, including the structure and function of the bladder.

Cancerous tumours of the bladder

Learn about the most common type of cancerous tumour of the bladder called urothelial carcinoma. It is also called transitional cell carcinoma (TCC).

Non-cancerous tumours and conditions of the bladder

Learn about non-cancerous tumours of the bladder. They do not spread to other parts of the body and are not usually life-threatening.

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