ENDOBRONCHIAL BIOPSY FOR SARCOIDOSIS: TIME TO RECONSIDER?

Abstract

TOPIC: Procedures TYPE: Original Investigations PURPOSE: Endobronchial biopsy (EBB) following thoracic lymph node sampling has been reported to increase diagnostic yield for pulmonary sarcoidosis in two studies. Given the widespread use of endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA), the purpose of this study is to investigate the diagnostic yield for EBB in contemporary sarcoid population at University of Minnesota Sarcoidosis Center of Excellence. METHODS: We identified a cohort of patients who underwent bronchoscopy with EBUS-TBNA and EBB and were found to have granulomatous inflammation on histopathology. Each patient underwent a standardized workup for sarcoidosis which included imaging and pulmonary function testing. Data regarding transbronchial lung biopsy (TBB), TBB histopathology, location of EBB and the presence of visual endobronchial lesions were recorded. A biopsy was regarded as positive if pathology demonstrated non-caseating granulomatous inflammation for which no specific cause was present. RESULTS: Our cohort included 25 patients (mean age 52.5±8.0 years; 53.8% male; 3.8% Blacks). Five patients (20%) had a positive EBB. All patients with positive EBB also had a postive EBUS-TBNA or TBB. Four patients (16%) in our cohort had visible endobronchial lesions, three of which had a positive EBB. Three (12%) patients the EBB was performed using a cryoprobe and all were positive, for a diagnostic yield of 100%. The remainder of the cohort had EBB performed with forceps, with a diagnostic yield of 9.1%. CONCLUSIONS: Based on our experience, the diagnostic yiedl of EBB is lower than previously reported, with only 20% of EBBs demonstrating granulomatous inflammation, compared to prior reports by Schorr et al (62%) and Goktalay et al (43%). However, instrumentation used for obtaining EBB as well as the presence of visible lesions may influence the diagnostic yield. Studies with adequate power are needed before implementing changes in clinical practice. When performed alongside both EBUS-TBNA and TBB, EBB did not add to the diagnostic yield in sarcoidosis. CLINICAL IMPLICATIONS: Currently, the data informing expert opinion on performing EBB following EBUS is lacking. The existing data implies that EBB increases diagnostic yield for pulmonary sarcoidosis following EBUS or TBB; therefore, should be routinely performed. Our experience questions the diagnostic impact of EBB during these procedures; whereby, more robust studies are needed to confirm our findings. DISCLOSURES: No relevant relationships by Maneesh Bhargava, source=Web Response Consultant relationship with Toray Industries Please note: 1/2021 to 9/2021 Added 04/21/2021 by Roy Cho, source=Web Response, value=Grant/Research Support No relevant relationships by Vidhu Pandey, source=Web Response No relevant relationships by David Perlman, source=Web Response