Chromobronchoscopy in the diagnosis of bronchial tumors

Staining of the bronchi with methylene blue was performed during bronchoscopy in 140 patients with various bronchopulmonary diseases. It was found that malignant bronchial tumors selectively stain dark blue; normal mucous membranes remain unstained. On this basis one can judge rather accurately how far the cancerous growth has spread along the bronchus, and so reach the target area by biopsy in those cases where visual signs of abnormality are indistinct or absent.