Supplementary Material for: Feasibility of Modified Endobronchial Ultrasound-Guided Intranodal Forceps Biopsy: A Retrospective Analysis

Background: Endobronchial ultrasound (EBUS)-guided intranodal forceps biopsy (IFB), a diagnostic bronchoscopic technique for intrathoracic lymphadenopathy, is performed following EBUS-guided transbronchial needle aspiration (TBNA). The current EBUS-IFB technique is complex and provides small sample volumes. We modified this technique to allow the use of standard-sized forceps. Objectives: The aim of this study was to assess the feasibility of the modified EBUS-IFB technique, which combines standard-sized forceps with standard EBUS-TBNA equipment. Method: This retrospective analysis included consecutive patients scheduled for EBUS-TBNA with attempted additional IFB between July 2020 and March 2021. The feasibility indices of IFB, technical success rate, diagnostic accuracy, and major complications were retrospectively investigated. We performed semi-quantitative evaluation of the histological specimens and univariable analyses to identify factors associated with IFB failure. Results: During the study period, 295 patients underwent 307 EBUS-TBNAs; 195 cases were included in the analyses. Target lesions were mainly mediastinal lymph nodes (134 cases, 68.7%); the most frequent sites were #7 (61 cases) and #4R (50 cases). The median lesion size was 16.1 mm, the technical IFB success rate was 90.8%, and the diagnostic accuracy of the TBNA and IFB combination was 99.5%. One patient was lost to follow-up. Univariable analyses did not identify any factors involved in technical IFB failure. Major complications of pneumonia and pneumothorax occurred in 2 cases (1.0%). The median histological score was significantly higher in the IFB group than in the TBNA group (1.67 vs. 1.50, p = 0.032). Conclusions: Modified EBUS-IFB, combining standard-sized forceps with common EBUS-TBNA equipment, is feasible with few major complications.