Non-small cell lung cancer is one of the types of lung cancer, and non-small cell lung cancer includes squamous carcinoma, adenocarcinoma, large cell lung cancer, etc. Common causes of lung cancer include smoking, air pollution, exposure to carcinogens and genetic factors. 1. Squamous carcinoma: squamous epithelial cell carcinoma, or squamous carcinoma for short, is one of the common types of lung cancer, accounting for about 85% of the total incidence rate of lung cancer, which is characterized by a history of smoking, and is more common in elderly men. 2. Adenocarcinoma: adenocarcinoma mainly originates from bronchial mucous glands, characterized by more females than males, local infiltration and hematogenous metastasis are earlier than squamous carcinoma, and it is easy to be metastasized to the liver, brain and bone, which is mainly due to the abundance of blood vessels in adenocarcinoma. 3. Large cell carcinoma: It is also known as large cell undifferentiated carcinoma, including giant cell carcinoma and clear cell carcinoma, with tumors occurring in the bronchial tubes near the hilum or the edge of the lungs, which is characterized by high malignancy, rapid growth and easy invasion of blood vessels to form extensive metastasis. Besides, non-small cell lung cancer also includes sarcomatoid carcinoma, adenosquamous carcinoma, salivary gland carcinoma and so on. When lung cancer is diagnosed, one should go to regular hospitals for consultation and treatment under the guidance of doctors.