Risk factors include the following: Smoking (the most common risk factor, causing ≥ 50% of new cases) Excess phenacetin use (analgesic abuse) Long-term cyclophosphamide use Chronic irritation (eg, in schistosomiasis, by chronic catheterization, or by bladder calculi) Exposure to hydrocarbons, tryptophan metabolites, or industrial chemicals, notably aromatic amines (aniline dyes, such as naphthylamine used in the dye industry) and chemicals used in the rubber, electric, cable, paint, and textile industries Types of bladder cancer include Transitional cell carcinomas (urothelial carcinoma), which account for > 90% of bladder cancers.