The occurrence of bladder cancer is a complex, multifactorial and multi-step pathological process, with both intrinsic genetic factors and extrinsic environmental factors. Two of the more clearly defined causative risk factors are smoking and long-term exposure to industrial chemical products. Chemical exposures can damage the DNA of normal cells, such as smoking, industrial chemicals, chemotherapy, etc. The environmental exposures mentioned above are called risk factors. Risk factors do not directly cause bladder cancer, just as not every smoker will get bladder cancer. However, in a population-based concept, smokers have an increased risk of developing cancer compared to nonsmokers. Exposure to these factors can increase the chance of DNA damage. When specific DNA that controls cell growth is damaged, normal cells have the potential to become cancerous. Cancer is characterized by an overgrowth of cells that push down and destroy surrounding normal tissue.
1. Tobacco: 25%-65% of bladder cancer patients smoke. The risk of bladder cancer in smokers is two to four times higher than in nonsmokers. The risk increases with the number of cigarettes smoked, the duration of smoking, and is related to the amount inhaled each time, regardless of gender. Quitting smoking can reduce the risk of bladder cancer, so it is not too late to quit. Other tobaccos such as cigars and smokeless tobacco, although to a lesser extent, can also increase the risk of bladder cancer. About half of all bladder cancers in Western countries are associated with smoking. The specific carcinogens in tobacco that cause bladder cancer have not been identified, and studies have shown that the presence of nitrosamines, 2-naphthylamines and p-aminobiphenyl in smoke increases the urinary metabolites of tryptophan in smokers. So all bladder cancer patients are advised to quit smoking immediately and permanently!
2. Occupational factors: Exposure to benzene dyes is the most common industrial risk factor for bladder cancer. Benzene dyes are a by-product of coal combustion. These fuels are used to dye wool or textiles. Other chemicals associated with bladder cancer include 2-naphthylamine, 4-aminobenzyl, 4-nitrobenzyl, 4-4-diaminobenzyl (p-diaminobiphenyl), and 2-amino-1-naphthylamine, as well as certain aldehydes used in the rubber and textile industries, coal combustion gases and soot, and possibly hydrocarbons. An increased risk of bladder cancer has been reported in the following occupations: auto workers, painters, truck drivers, drillers, leather workers, metallurgists, mechanics, dry cleaners, paper makers, weavers, dental technicians, barbers, cosmetologists, internists, garment workers, and plumbers.
3, chronic infection: chronic bacterial infection, schistosomiasis infection, foreign body, urinary tract obstruction, stones, bladder leukoplakia, pelvic leukoplakia, adenocystitis, etc. may be the cause of squamous carcinoma and adenocarcinoma. Adenocarcinoma often occurs in those with bladder exstrophy and unclosed umbilical ureter.
4.Drugs: Taking large amounts of painkillers containing finasteride can increase the risk of bladder cancer, and the drug is now discontinued. The risk of bladder cancer in patients with lymphoma treated with cyclophosphamide can be increased several times, and the tumor is often infiltrative.
5.Pelvic radiotherapy: pelvic radiotherapy can increase the risk of bladder cancer. Women who receive pelvic radiotherapy for cervical or ovarian cancer have a 2-4 times increased risk of bladder cancer. This risk increases even more when radiotherapy is combined with chemotherapy. The risk of bladder cancer is also increased in male patients receiving radiotherapy for prostate cancer.
6. Chemotherapy and immunosuppressive therapy: Chemotherapy with cyclophosphamide can increase the risk of bladder cancer by 9 times and the aggressiveness of the tumor is higher. In addition, patients who receive kidney transplants or other organ transplants are more likely to develop bladder cancer because of the use of immunosuppressive drugs (steroids and other drugs).
7. Dehydration: The risk of bladder cancer is increased in people who consume very little fluid. Very little fluid intake concentrates the urine and prolongs the interval between urination. Retaining concentrated urine in the bladder for a long time may increase the risk of bladder cancer.
8.Artificial sweeteners: Studies in the late 1970s reported that sweeteners could increase the risk of bladder cancer in men by 60%, but studies since then have failed to confirm the correlation, so currently the International Agency for Research on Cancer no longer includes sweeteners as carcinogens of human bladder cancer.
Carcinogens in drinking water: Drinking tap water disinfected by chlorine and containing chlorinated by-products can increase the risk of bladder cancer; arsenic contamination in drinking water in Taiwan and Argentina, South America is also associated with increased risk of bladder cancer.
10.Coffee: The risk of bladder cancer is higher in coffee drinkers than in non-drinkers, but there is no dose and time trend between the two.
11. Heredity and infectiousness: There is no very conclusive evidence that bladder cancer is inherited from parents to their children. Family members are prone to be exposed to similar risk factors. In some cases, several people within a family develop bladder cancer at the same time, but there may be different risk factors among family members, such as smoking or environmental factors. However, it is safe to assume that most people with bladder cancer do not have a clear family history of bladder cancer. Bladder cancer is not an infectious disease, so it is not contagious to your family or friends. However, as mentioned above, family members of bladder cancer patients are prone to be exposed to similar risk factors, such as smoking, environmental chemicals and other harmful substances. Therefore, they may have a higher risk of developing bladder cancer than normal people. The risk of bladder cancer in the immediate family of bladder cancer patients is about twice as high as that of those without a family history, and the risk is even higher in the immediate family of young bladder cancer patients.
12. Fat and cholesterol intake: Some studies suggest a low-fat, low-cholesterol diet to reduce the risk of bladder cancer. A recent study from Japan found that a diet rich in green vegetables or carrots can reduce bladder cancer risk. Soy protein and garlic intake may also reduce this risk. Garlic has a direct killing effect on bladder cancer cells. This is due to the body’s natural defense mechanism to kill cancer cells being triggered.
13, vitamins: In a study involving one million adult smokers, the risk of dying from bladder cancer was reduced in people who took vitamin E as a rule for more than ten years. This had a smaller effect in the non-smokers. However, smokers who consumed vitamin E still had a high risk of bladder cancer; therefore, quitting smoking is quite important! The risk of bladder cancer was not reduced in those who consumed vitamin C.