Bladder cancer is one of the commonest conditions treated by urologists. Bladder cancer arises owing to damage to the lining of the bladder (bladder mucosa) caused by various chemicals, drugs and carcinogens in products such as cigarettes. These compounds are concentrated and excreted in the urine, and cause damage to the DNA of bladder mucosa cells, resulting in pre-cancerous changes. Accumulation of these changes eventually leads to cancer.
By far the commonest type of bladder cancer is "transitional cell" cancer, which arises from the typical lining cells of the bladder. This cancer can vary from a small, non-aggressive polyp on the surface of the bladder lining (much like a polyp in the colon) to an aggressive, invasive tumour, which invades through all the layers of the bladder, into the bladder muscle and sometimes beyond. Bladder cancer that has invaded into the muscle wall of the bladder is very serious and is most commonly treated by the removal of the bladder completely. Fortunately this aggressive form is not a common presentation, accounting for about 15% of first time cases.
Treatment of bladder cancer involves removing the tumour with a urological endoscope via the urethra. This is done carefully as the bladder is very thin, and the pieces of tissue are sent to the lab for analysis. This tells the surgeon what kind of tumour it was and how aggressive, and whether any further treatment is necessary.
Bladder cancer is characterised by its recurrent nature. This means that patients who have had one tumour are at high risk of getting another tumour in the bladder later, even many years after the first episode. For this reason, patients are advised to go regular surveillance of the bladder (check cystoscopies - "cysto" = bladder, "scope" = to look). This is initially done every 3 months for the first year, then less frequently, but at least annually in most patients. Some types of bladder cancer require extra treatment with chemicals that are instilled inside the bladder - these can be a form of mild chemotherapy that remains in the bladder only - for example "Mitomycin C", or a form of bladder immune therapy using BCG - Bacille Calmette Guerin - the same attenuated tuberculosis bacteria used for TB vaccinations. These therapies can reduce the frequency of recurrence of bladder tumours, and delay progression to more aggressive forms. However they do not work in every patient, and surveillance is still needed with regular check cystoscopies.