Bladder Cancer

Overview

The bladder is a hollow organ in the lower abdomen. Its primary function is to store urine, the waste that is produced when the kidneys filter the blood. Urine passes from the two kidneys into the bladder through two tubes called ureters and urine leaves the bladder through another tube called the urethra. The bladder has a muscular wall that allows it to get larger and smaller as urine is stored or emptied.

The wall of the bladder is lined with several layers of cells called transitional cells. Cancer arising from these cells makes up more than 90% of all bladder cancers and these are referred to as transitional cell carcinomas. Because transitional cell carcinomas are the most common type of bladder cancer, the information in this section only addresses treatment of transitional cell cancer of the bladder.

Bladder cancer occurs predominantly in elderly men and less frequently in women and younger men. Many bladder cancers are thought to be caused by exposure to cancer-causing agents that pass through the urine and come into contact with the bladder lining. The most important risk factor for bladder cancer is smoking, which increases risk by at least four-fold.[1]

The most common sign of bladder cancer is hematuria or blood in the urine, which will turn the urine rust or red in color.[2] Other signs of bladder cancer may include pain during urination and frequent urination. Most patients with bladder cancer do not have symptoms other than hematuria. Unfortunately, most bladder cancers are not diagnosed until they have become very large. As a result, research is ongoing in order to develop urine tests that would enable earlier detection of bladder cancer when it is small and more easily treated. There are several promising tests under evaluation, but currently none are reliable enough for routine use.

An outpatient procedure called a cystoscopy is usually used to diagnose bladder cancer. During a cystoscopy, the physician (a urologist) inserts a thin, lighted tube (cystoscope) into the bladder through the urethra to examine the internal lining of the bladder. The procedure enables the urologist to remove (biopsy) small samples of any abnormal appearing areas of the bladder and examine them under the microscope. When bladder cancer is diagnosed, the urologist will want to learn the stage or extent of the cancer, as well as the grade (aggressiveness) of the cancer as determined by its appearance under the microscope. Grade is important because it indicates how closely the cancer resembles normal tissue and suggests how fast the cancer is likely to grow. Low-grade cancers more closely resemble normal tissue and are likely to grow and spread more slowly than high-grade cancers.