Final answer:
The major risk factor of lung cancer is tobacco smoking, accounting for about 85% of cases and is compounded by additional environmental risk factors such as radon, asbestos, and air pollutants. Family history also plays a role in increasing the risk. Primary lung cancer originates in the lung, while secondary lung cancer spreads from other parts of the body.
Step-by-step explanation:
Major Risk Factor of Lung Cancer
The major risk factor of lung cancer is tobacco smoking, which is attributed to about 85 percent of cases. Cigarette smoke is laden with numerous cancer-causing chemicals which increase the risk of developing lung cancer. Additionally, environmental risk factors such as exposure to radon gas, asbestos, secondhand smoke, and other air pollutants are also significant contributors to the risk of lung cancer. It is particularly noteworthy that the combination of smoking with these environmental risk factors substantially raises the risk of lung cancer compared to each factor alone.
People with a family history of lung cancer have an increased risk as well. It is important to recognize that while primary lung cancer begins in the lungs, secondary lung cancer starts elsewhere in the body and metastasizes to the lungs. Symptoms of lung cancer often include coughing, wheezing, shortness of breath, chest pain, and weight loss. The mitigation of these risk factors, especially smoking cessation, is critical for lung cancer prevention.