Background: Guidelines recommend multiple types of cytologic and tissue samplings in the diagnosis of lung cancer by bronchoscopy, but differences of opinion exist as to the relative value of bronchial brushings and endobronchial or transbronchial biopsies. Our objective was to determine concordance of these procedures by a test of symmetry in a historical cohort referred to the pulmonary diagnostic laboratory.
Methods: From 1988 to 2001, patients with pathologic confirmation of primary lung cancer were examined by standard bronchoscopic techniques of that period. An electronic medical record system was used, with statistical analysis of symmetry between brushings and biopsies establishing the diagnosis.
Results: Of 968 patients, 98% had bronchoscopy for 624 central and 322 peripheral suspect lesions. Bronchial brushings from 915 patients confirmed pulmonary malignancy in 811 (89%) patients. Endobronchial or transbronchial biopsies from 739 patients showed lung cancer in 603 (82%) cases. Bronchial washings in 16 patients and transthoracic needle biopsies in 30 patients established diagnosis. Transbronchial needle aspiration of mediastinal nodes identified metastases in 94 patients. Only 14 patients required a surgical procedure for diagnosis, but 188 received surgical excision as primary treatment. Statistical evaluation used only patients with both bronchial brushings and endobronchial or transbronchial biopsies. Analysis by a test of symmetry showed a significant difference (P<0.0001).
Conclusions: Positive, suspicious, and negative specimens were consistent, with bronchial brushings being more sensitive with a lower false-negative rate than endobronchial or transbronchial biopsies. Multiple techniques are recommended for bronchoscopic confirmation of lung cancer, but bronchial brushings should be collected initially, as technical or patient limitations might preclude diagnostic tissue biopsies.