Background: Bronchoscopy is a minimally invasive procedure used for the diagnosis of lung cancer. Aim: To report our experience with bronchoscopy and transbronchial biopsies for the diagnosis of potentially malignant pulmonary lesions. Material and methods: Revision of electronic records from patients who underwent transbronchial biopsies seeking for lung cancer. The diagnostic yield of the procedure was evaluated using pathology reports or a 24 months follow up. Results: 261 patients were included. Bronchoscopy was diagnostic in 65% of cases. Lesions mean diameter was 51 mm (range 9-120 mm). Diagnostic yield for lesions less than 30 mm was 59%, for lesions less than 35 mm was 61%, and for lesions over 40 mm was 69%. The presence of malignant lesions and their location in the superior or middle lobe were associated with a better predictive value of the procedure. TNM staging was IIIB/IV in 80% of the patient at the time of diagnosis. Conclusions: The diagnostic yield of bronchoscopy is influenced by the etiology and location of lung lesions.Background: Bronchoscopy is a minimally invasive procedure used for the diagnosis of lung cancer. Aim: To report our experience with bronchoscopy and transbronchial biopsies for the diagnosis of potentially malignant pulmonary lesions. Material and methods: Revision of electronic records from patients who underwent transbronchial biopsies seeking for lung cancer. The diagnostic yield of the procedure was evaluated using pathology reports or a 24 months follow up. Results: 261 patients were included. Bronchoscopy was diagnostic in 65% of cases. Lesions mean diameter was 51 mm (range 9-120 mm). Diagnostic yield for lesions less than 30 mm was 59%, for lesions less than 35 mm was 61%, and for lesions over 40 mm was 69%. The presence of malignant lesions and their location in the superior or middle lobe were associated with a better predictive value of the procedure. TNM staging was IIIB/IV in 80% of the patient at the time of diagnosis. Conclusions: The diagnostic yield of bronchoscopy is influenced by the etiology and location of lung lesions.