Causes And Statistics Of Bladder Cancer
From WebHealth
Causes And Statistics Of Bladder Cancer
Bladder cancer is a disease of the elderly with a peak at around 60 to 70 years. In the U.S. the male to female ratio is about 3 to 1. However, in the last few years more women are seen to develop it due to the increased number of women who started to smoke in the past decades. The lag period for developing bladder cancer from exposure to cigarette smoke is 19 plus minus 3 years.
The relative risk ratio for both whites and blacks is about 1.6 every year of exposure. Occupational risks are common: exposure to aniline with dye workers, working with organic chemicals such as aryl amines, aniline, dye, rubber and paint leads to an increased risk of bladder cancer. Exposure to diesel fumes or exhaust from cars in urban areas has not been linked to bladder cancer. Chronic abuse of phenacetin in the past, particularly in the Swiss watch industry, was linked to bladder cancer.
After initial suggestions in animal models that dietary sweeteners might promote bladder cancer development when carcinogens were given at the same time, four well controlled studies in humans could not show any bladder cancer from cyclamate and saccharin. It is interesting that many people still hold on to the fears that were generated by the popular press generated from these poorly conducted animal experiments despite the proof that diet sweeteners are safe from a cancer perspective. The strongest association that is reported in the literature is that between cigarette smoking and bladder cancer.
Study after study shows an association between the amount of cigarettes smoked, the duration of years of exposure and bladder cancer risk. The more and the longer people smoke, the more the carcinogens attack the very susceptible bladder lining leading to changes in the cell structure.
The end result is whqat physicians call a "transitional cell carcinoma", just a fancy name for "bladder cancer". 95% of bladder cancers are of this pathological type (Ref. 1 and 2).
Chronic bilharziasis (also called "schistosomiasis") leads to a chronic bladder irritation and bladder ulcerations, followed by the development of papillomatous masses in the bladder, which often turn into bladder cancer. This is not a problem in the U.S., but is very common in other countries such as in African countries, also in Brazil, Venezuela, some Carribbean islands, China, the Phillipines, Laos and Cambodia.
The bladder cancer producing effect of bilharziasis is as strong as exposure to cigarette smoking and if the person affected with bilharziasis smokes at the same time, the bladder cancer causing effect gets even more pronounced.
Patients with bladder infections, particularly when these are chronic recurrent, have a higher risk for bladder cancer. The mechanism for this has been well researched and was found to be due nitrates as well as nitrosurea, which is produced by the bacteria in chronic bladder infections. This type of mechanism leads to a different histological type of bladder cancer, called "squamous cell carcinoma", which is only found in about 3% of all bladder cancers. A minority of bladder cancer cases is caused by genetic factors, partially because of chromosomal breaks, chromosomal deletions or alterations. There are also familial genetic syndromes, where patients younger than 45 years of age come down with bladder cancer.
There is a suggestion that milk and vitamin A protects from the development of bladder cancer.
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References:
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