回顾总结由X线平片发现，经支气管体层摄影、CT扫描、纤维支气管镜检查，最后由手术、病理证实的中心型肺癌42例。这42例在首次X线胸片检查时均无肺癌诊断。追溯其首次X线平片表现：均有不同程度的阻塞性肺气肺、阻塞性肺炎、阻塞性肺不张，即“三阻征”。“三阻征”是中心型肺 Review and summarize the findings of X-ray plain film, transbronchial tomography, CT scan, fiberoptic bronchoscopy, and finally 42 cases of central lung cancer confirmed by surgery and pathology. These 42 patients had no lung cancer diagnosis on the first X-ray examination. To trace its first X-ray film performance: There are different degrees of obstructive pulmonary pneumoconiosis, obstructive pneumonia, obstructive atelectasis, the “triple resistance sign.” “Three resistance sign” is a central lung