Health encyclopaedia - Alphabetical Topic List
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Causes of Cancer of the bladder
The causes of most bladder cancers remain uncertain, but some causes are known.
These include:
- The products of tobacco tars acquired by cigarette smoking and excreted in the urine.
- Certain chemicals such as aniline dyes, beta-naphthylamine and benzidine
- Some chemicals encountered in rubber manufacture
- Drugs such as phenacetin and cyclophosphamide
- Long-term bladder inflammation
- The African parasitic disease schistosomiasisThe presence of bladder stones
The changes in the bladder lining that lead to cancer occur gradually and progressively. The most important of the known causal factors are the substances alpha and beta naphthylamine, which are excreted into the urine of cigarette smokers. Heavy cigarette smoking is believed to be the cause in half the cases in men and a third of the cases in women.
Exposure to occupational chemicals, especially in the rubber, petroleum, leather and dye industries, probably cause about 30 per cent of cases in men. Artificial sweeteners were at one time suspected of causing bladder cancer, but several research projects have failed to confirm any causal link.
In almost all bladder cancers, the cancer cells show a loss of part of the long arm of chromosome number 9. Many bladder cancers also show loss of the short arms of chromosomes 11 and 17. The supposition is that the cancer may be caused by loss of suppressor genes on these chromosomes.
