A comparison of standard and novel bronchoscopic endobronchial biopsy retrieval methods

Background: The targets of bronchoscopic biopsy now include not only adequate tissue for histologic diagnosis but also tissue for further analysis. We prospectively compared standard and novel bronchoscopic endobronchial biopsy (EBB) retrieval methods attempting to increase tissue yield. Methods: EBB samples were retrieved using techniques A, B, and C using a standard forceps. Method A is routinely performed conventional method, where as in method B, biopsy forceps was left protruded from the bronchoscope and in method C, both valve and forceps were removed to prevent the loss of specimen. At least 6 EBB were retrieved per patient. Results were compared with gold standard composite of confirmatory pathological or clinic-radiologic follow up. Results: A total of 42 of 43 patients completed the study. The final gold standard diagnosis was cancer [non-small cell lung cancer, metastatic, carcinoid, carcinoma in situ (24)], benign disease [sarcoid, amyloid, hamartoma, and chondroid tumor (4)], and benign/nonspecific inflammation (14). EBB retrieved using standard method A were smaller than novel methods B and C (P=0.03). However, the percentage of cases where blood was the predominant component ( > 50%) was less by standard methods A (4/42) than B (16/42) and C (20/42) (P=0.001). There was no difference in mean viable tumor area (n=23, sensitivity for EBB for cancer 96%) between groups A compared with B and C (P 0.27) and adequacy in benign cases by subepithelial depth ( > 0.3 mm) (P=0.38). Conclusion: Standard retrieval of endobronchial biopsies through the bronchoscope and cap does not reduce the size of viable tissue and reduces contaminating blood and necrotic material.