Bladder cancer is the most common malignant tumor of the urinary system, and its incidence rate ranks first among malignant tumors of the urinary system. The cause of the disease is still unclear, but it is generally believed to be related to frequent contact with carcinogens such as naphthylamine and benzidine. Dyes, rubber, plastic products, paints, detergents, etc. commonly seen in daily life also have potential carcinogenic risks. Smoking is not only harmful to the respiratory system, but also causes bladder cancer. In addition, certain diseases such as leukoplakia, glandular cystitis, urethral stones, and urine retention may also induce bladder cancer. The incidence rate of bladder cancer in men and women is about 5:2, and there are about 54,500 new cases in the United States each year (estimated in 1997).