[Radiographic diagnosis of lung cancer and lymph nodal metastasis of the mediastinum].

Primary lung cancer is divided into two types: peripheral type and hilar or central type. Peripheral lung cancer appears as a solitary mass or patchy shadow and is typically lobulated or irregular in shape. Any regular or scattered calcification within or around the lesion on routine radiographs indicates that it is benign. Hilar or central lung cancer may accompany hilar and mediastinal lymphadenopathy, lobar collapse and consolidation, and pneumonitis distal to a mass in a large bronchus. In addition, it is very important that the metastases of the hilar and mediastinal lymph nodes are detected preoperatively or prior to conservative therapy. On 44 cases of lung cancer pathologically proved, the diagnostic accuracy of the metastases of the hilar or mediastinal lymph nodes is 42.4% preoperatively on routine radiographs.