Abstract

Cancer refers to diseases in which abnormal cells divide out of control and are able to invade other tissues. Cancer
cells can spread to other parts of the body through the blood and lymph systems, which help the body get rid of
toxins, Lung cancer is the most frequent malignant tumor with the highest mortality around the world. The most
common clinical manifestations are coughing, weight loss, and shortness of breath and chest pain. Globally, lung
cancer is the most common cancer and the leading cause of cancer death in men and is the third most common cancer
and the second leading cause of cancer death in women. About 1.8 million new cases of lung cancer were diagnosed
in 2012, which accounted for 12.9% of the world’s total cancer incidence. The worldwide lung cancer mortality rate
amounted to 1.59 million deaths in 2012, accounting for 19.4% of the total cancer deaths. Lung cancers was
uncommon before the advent of cigarette smoking it was not even recognized as a distinct disease until
1769.Smoking is a known major risk factor for lung cancer, so lung cancer epidemiologic trends, and its variations,
reflect the past trends of cigarette smoking to a great extent. In the United States, most states drew up legislation for
smoking restrictions in public areas about 20 years ago and have continually promoted the awareness of smoking
hazards to their residents. Many states have passed the peak of the tobacco related epidemic, therefore both the
incidence and mortality rates of lung cancer in these areas are decreasing. Healthy lifestyle behaviors for cancer risk
reduction include a healthy diet, weight management, regular exercise, reduction in alcohol consumption and smoking
cessation lifestyle could modify cancer risk factors