[Mediastinoscopy--indications, efficiency, and morphologic findings in more than 2250 investigations (author's transl)].

2276 diagnostic mediastinoscopies were performed and their efficiency was analysed. Except from patients with bronchial carcinomas, in 80% of all cases pathologic findings with diagnostic significance could be found in the lymph-nodes. CARLENS mediastinoscopy proved to be less efficient in the prognostic evaluation of bronchial carcinomas. In 521 patients with bronchial carcinomas only 146 (28%) showed mediastinal lymph-node metastasis detected by mediastinoscopy. But in the remaining 375 cases the operation revealed in 51.5% the occurence of perihilar metastatic lymph-nodes. The most important morphological findings in lymph-nodes and their differentialdiagnostical problems are discussed with reference to sarcoidosis, sarcoid-like reaction, tuberculosis, and silicosis.