肺癌的发病率随年龄的增长而升高,普遍认为40岁以后发病开始增高,在40岁前较少见。因此公认的肺癌高危人群系指40岁以上男性,每日吸烟20支以上,特别是吸烟20年以上者。我们的统计发现低年龄组小于39岁(含39岁)的肺癌已并不少见,应当引起足够重视。1　临床资料1.1　一般资料　我 The incidence of lung cancer increases with age, and it is generally believed that after the age of 40, the onset begins to increase and it is less common before the age of 40. Therefore, the recognized high-risk population of lung cancer refers to men over the age of 40 who smoke more than 20 cigarettes per day, especially those who smoke for more than 20 years. Our statistics show that lung cancer in the younger age group, less than 39 years old (including 39 years old), is not uncommon and should be given enough attention. 1 Clinical Data 1.1 General Information I