Hai doc my cousin is 15 your old she is smoker but she stop to smoke she can get a lung cancer or not?

Unlikely: If she is only 15 years old it would be very unlikely to have lung cancer at this age. However, this is a great time to stop smoking completely. Otherwise the risk of lung cancer will be higher and higher with every cigarette that she smokes. So please encourage her to stop. This is the perfect age to do it. This is the best she can do for her health. Best wishes and good luck. Ariel.

Yes, but...: The most important thing is to stop now and not continue. Cancers for the most part develop over numerous years. Smoking related lung cancer at age 15 is unlikely. But, any smoking does add increase for risk in the future. Further, individuals that "never smoked" can still develop lung cancer. Check this link: http://goo.Gl/q3itr.

85%+ of: Lung cancer caused by tobacco, more in males. Stopping before age 35 decreased risk to that of non-smokers. But there is no guarantee. Never smoking is best quitting young second best, but quitting at any age decreases risk. And it is not just ling cancer (head and neck, esophagus, bladder), heart, vascular, and lung deaths too.