The issue is, if you continue to smoke it's VERY unlikely you'll remain at only 1 -2 cigs per day.
However, some people smoke moderately to heavily all their lives and never develop lung cancer. Some people never smoke a single drag and do develop lung cancer.
No one can tell you if you will develop it or not...but smoking does increase the risks, as well as risks of heart disease and other illnesses because of the effects it has on the body. For example, smoking causes your blood to thicken, thus blood pressure issues could arise. That can be potentially serious.
The best way to prevent cancer, is to not participate in the behaviors that raise your risk of getting it. ☺