The percentage of smokers who get cancer varies depending on the type of cancer and the duration and frequency of smoking. According to the Centers for Disease Control and Prevention (CDC), lung cancer develops in around 10 to 20 percent of all smokers. However, this statistic only applies to lung cancer, and smoking is responsible for over 80 percent of lung cancers. The likelihood of getting lung cancer greatly increases after a few times smoking cigarettes due to the addictive nature of nicotine and the highly toxic chemicals from cigarettes released into the lungs. The percentage of developing lung cancer may also vary as the patient grows old.

A study led by scientists at Albert Einstein College of Medicine suggests that some smokers may have robust mechanisms that protect them from lung cancer by limiting mutations. The findings could help identify those smokers who face an increased risk for the disease and therefore warrant especially close monitoring.

Lifetime risks of developing lung cancer were estimated for six hypothetical cohorts in Canada. It was found that 172/1,000 of male current smokers will eventually develop lung cancer; the similar probability among female current smokers was 116/1,000. For those who never smoked on a regular basis, the lifetime risk was substantially reduced. Only 13/1,000 males and 14/1,000 females in this category will develop lung cancer.

A study found that, by 80 years of age, 48.3% of current smokers will develop cancer, as opposed to 41.1% of people who dont smoke. However, its difficult to quantify how long you have to smoke to get cancer, and any amount of smoking seems to increase your risk of developing cancer, especially lung cancer.

In summary, the percentage of smokers who get cancer varies depending on the type of cancer and the duration and frequency of smoking. For lung cancer, the percentage is around 10 to 20 percent of all smokers, but the likelihood of getting lung cancer greatly increases after a few times smoking cigarettes due to the addictive nature of nicotine and the highly toxic chemicals from cigarettes released into the lungs.