What is the most important risk factor for bladder cancer?

• A. Obesity
• B. Cigarette smoking
• C. Alcohol consumption
• D. High-sodium diet

Answer: (B)

Cigarette smoking is the strongest risk factor for bladder cancer because carcinogens in tobacco smoke, especially aromatic amines and polycyclic aromatic hydrocarbons, are absorbed, processed, and excreted in urine. As these chemicals are concentrated in the urine, they come into direct contact with the bladder’s urothelium, causing DNA damage that drives malignant transformation. The risk increases with how much and how long a person smokes, and quitting lowers risk over time, though it may remain higher than in those who never smoked for many years. This makes smoking far more impactful than obesity, alcohol use, or a high-sodium diet when it comes to bladder cancer risk. In practice, smoking cessation is a key preventive measure for reducing risk.