患者男,41岁。因反复咳嗽伴左胸隐痛3个月余入院。入院前在外院行胸部X线片检查诊断为左胸腔积液合并左下肺炎,予抗感染治疗后无好转,遂于外院行胸部CT检查示:左前下纵隔大片均质低密度影,延伸到前上纵隔,拟畸胎瘤可能,伴左下肺受压不张。于我院行CT检查诊断:脂肪瘤 Patient male, 41 years old. Due to repeated cough with left chest pain more than 3 months admitted to hospital. Before admission in the hospital outside the chest X-ray examination was diagnosed with left pleural effusion with left lower pneumonia, to anti-infection treatment did not improve, then in the outside hospital chest CT examination showed: large anterior left inferior mediastinum large homogeneous low density, extending to the front The mediastinum, the teratoma may be accompanied by left lower pulmonary compression atelectasis. CT examination in our hospital diagnosis: lipoma