Endobronchial Biopsies in the Diagnosis of Lung Lesions — A Study of 204 Consecutive Cases from a Single Center in Southern India

Abstract

Objectives: The objective of this study is to evaluate the diagnostic yield of endobronchial biopsy in various neoplastic and nonneoplastic lung lesions. Patients and Methods: A total number of 204 consecutive cases of fiberoptic bronchoscopic-guided endobronchial biopsies was analyzed. The bronchial wash (BW) samples collected simultaneously during the biopsy were correlated with final histopathology diagnosis. Results: The bronchoscopic findings mainly included endobronchial mass, increased mucosal vascularity, and mucosal irregularities. Of the 184 adequate biopsy samples, 32.3% were neoplastic, 20.5% nonneoplastic, and remaining 41.3% revealed normal histology. The nonneoplastic lesions included mainly nonspecific inflammation, granulomatous inflammation followed by few cases of squamous metaplasia, one case each of tracheobronchopathia osteochondroplastica, mycobacterium spindle cell pseudotumor, and cytomegalovirus infection. Among the malignant tumors, adenocarcinoma (ADC) was the most common followed by squamous cell carcinoma (SQCC) and non-small cell carcinoma-not otherwise specified. On immunohistochemistry, Napsin-A showed better sensitivity than thyroid transcription factor-1 for ADC. P40 was found to be most sensitive and specific markers for SQCC. Neuroendocrine tumors included seven small cell carcinoma and three carcinoids. Both chromogranin and synaptophysin were found to be equally sensitive neuroendocrine markers. The bronchoscopically normal airways mostly revealed normal histology with few showing mild nonspecific inflammation. On the contrary, all except one case of neoplasm had mass lesions on bronchoscopy. Conclusion: EBB provides sufficient tissue for morphological and immunohistochemical characterization of malignant lesions. BW cytology has poor concordance with EBB in the diagnosis of malignancies with nearly 70% cases being false negative.