Not only is smoking a leading cause of lung cancer, but the nicotine in cigarettes might hurt the immune system's response to growths, a doctor said Thursday.
The length of time and the number of cigarettes per day a person smokes both factor into the chances of lung cancer, said Dr. Taing Tek Hong, as a guest on "Hello VOA" Thursday.
The sooner a person stops smoking, the lower the risk of lung cancer, he said.
Symptoms of lung cancer include shortness of breath, chronic coughing, coughing up blood, chest pain, a hoarse voice and difficulty breathing, Taing Tek Hong said.
Other causes of lung cancer include radon gas and asbestos, he said.