肺癌在中老年人中较为常见,但在40岁以下年龄组中则较为少见。美国西弗吉尼亚州Charleston Area医疗中心,自1965年至1985年收治肺癌4024例,其中52例年龄在40岁以下(1.2％)。 52例患者年龄20～39岁,平均36岁,男35例,女17例。男女比例约为2:1。咳嗽、胸痛、咯血和呼吸困难等最常见症状较40岁以上 Lung cancer is more common in middle-aged and elderly people, but it is rarer in the 40-year-old age group. The Charleston Area Medical Center in West Virginia, USA, had 4,024 lung cancers treated from 1965 to 1985, 52 of which were under 40 (1.2%). 52 patients aged 20 to 39 years old, an average of 36 years old, 35 males and 17 females. The ratio of male to female is about 2:1. The most common symptoms are cough, chest pain, hemoptysis and dyspnea more than 40 years old