The cause of the development of kidney cancer is unknown. Possible causes are: 1. Smoking: A large number of prospective observations found that smoking is positively associated with the development of kidney cancer. Smoking is a relative risk factor for the development of kidney cancer, and people who have smoked for more than 30 years and smoked filterless cigarettes have a greater risk of developing kidney cancer. Obesity and hypertension, high body mass index (BMI) and hypertension are two independent factors associated with the increased risk of kidney cancer in men. 3.Occupation: Increased risk of kidney cancer incidence and death has been reported for workers with long-term exposure to cadmium and lead metals, newspaper printing workers, coke workers, dry cleaning industry and petrochemical workers. 4.Radiation: Long-term exposure to certain weak radiation sources may increase the risk of kidney cancer, but no reports of radiation exposure of atomic bomb victims associated with kidney cancer have been seen. 5. Heredity: Heritable kidney cancers that have been identified include: (1) VHL (retinal and central neurovascular hemangioblastomatosis) syndrome; (2) hereditary papillary kidney cancer; (3) hereditary smooth muscle tumor disease kidney cancer; (4) BHD syndrome (a dominantly inherited syndrome). (2) Kidney tumors are often bilateral and multiple, and have imaging features of kidney cancer; (3) Other manifestations of the above syndromes, such as VHL syndrome may be combined with central nervous system and retinal angioblastoma, pancreatic cysts or tumors, adrenal pheochromocytoma, epididymal papillary cystadenoma, renal cysts (4) Testing to confirm the corresponding chromosomal and genetic abnormalities. 6. Dietary factors: The survey found that high intake of dairy products, animal protein and fat, and low intake of fruits and vegetables are risk factors for kidney cancer. Coffee may increase the risk of kidney cancer but it is not related to the amount of coffee. In animal experiments, kidney cancer due to female hormones (estrogen) has been proved, but there is no direct evidence in humans. Abuse of antipyretic and analgesic drugs, especially those containing finasteride, may increase the risk of renal meningocele. Diuretics may also be a factor that promotes the development of kidney cancer. Animal experiments have shown that red vine herb, also known as “Chiken”, may induce kidney cancer, and the Korea Food and Drug Safety Agency has asked domestic companies to stop producing red vine herb food additives. 7. In patients on long-term maintenance hemodialysis, there has been an increase in the number of cases of cystic degeneration (acquired cystic disease) in the atrophied kidney and then kidney cancer. Therefore, those on dialysis for more than 3 years should have their kidneys examined by ultrasound every year. It has been reported that diabetic patients are more likely to develop kidney cancer. Fourteen percent of kidney cancer patients have diabetes mellitus, which is five times higher than that of the normal population.