Are there different types of bladder cancer?
The most common type of bladder cancer that we see in the United States and the Western world is transitional cell carcinoma of the urinary bladder. Transitional cell refers to the cell type that lines the urinary bladder. This type of cell lines the bladder, the ureters that drain urine from the kidney down to the bladder, and also the urethra, where urine is transported outside the bladder. The cancer that starts from these cells is therefore called transitional cell carcinoma. About 85 to nearly 90% of the bladder cancer that we see in this country is of the transitional cell variety. There are different types of cancers - squamous carcinoma is also seen. This tends to be a little bit more of an aggressive type of cancer. It tends to be associated with different risk factors, primarily chronic infection and chronic inflammation and irritation. It can be seen in this country associated with chronic catheter use or bladder stones. In other parts of the world, especially Northern Africa and Egypt up the Nile Valley, there's a strong association with a parasitic infection called Schistosomiasis or Bilharziasis, in which the parasite invades the bladder. The most common type of cancer seen in that part of the world is not transitional cell carcinoma but squamous cell carcinoma, and the treatment is quite different for that kind of tumor. In addition to these two, there are some rarer cancers - adenocarcinoma of the bladder is seen, ring cell carcinoma, and mucinous carcinoma of the bladder. There is finally a urachal carcinoma or a urachal variant, which is probably the rarest in this country. Urachal carcinoma refers to its origins in the urachus, which is the remnant of the umbilical cord connecting to the dome of the bladder.
