PERFORMANCE OF 19-GAUGE NEEDLE DURING EBUS-TBNA IN THE DIAGNOSIS AND TESTING OF MOLECULAR MARKERS IN LUNG CANCER

Abstract

SESSION TITLE: Wednesday Electronic Posters 4 SESSION TYPE: Original Inv Poster Discussion PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM PURPOSE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has become the standard for diagnosis and staging of lung cancer. Needle aspirates of mediastinal lymph nodes can provide cytologic diagnosis as well as specific tumor biomarkers that provide important information to guide targeted therapy. Historically 21-gauge and 22-gauge needles have been paired with EBUS. We evaluated the performance of EBUS-TBNA using a 19-gauge needle in the assessment of tumor tissue obtained and success of testing for molecular markers. METHODS: We prospectively enrolled adult patients with mediastinal lymphadenopathy concerning for metastatic lung cancer in two academic medical centers. Patients underwent diagnostic EBUS-TBNA utilizing 19-gauge needles. All cases were evaluated with on-site cytology and cell blocks were prepared and evaluated by pathology. Cases of non-small cell lung cancer (NSCLC) were evaluated for presence of PD-L1. Cases of Adenocarcinoma were evaluated for three molecular markers: EGFR, ROS-1, and ALK. RESULTS: Fifty patients were enrolled and had the following cancer diagnoses: 32% with adenocarcinoma, 30% with small cell cancer, 26% with squamous cell carcinoma, 6% with undifferentiated NSCLC, 4% with other types of pulmonary cancers and 2% with carcinoma of unknown primary. Average number of needle passes was 5. Block quality was judged by total number of tumor cells per H&E stained slide of each cell block (58% of specimens had >500 cells and 22% had 200-500 cells), average number of tumor cells in 10 high power fields of the area containing the highest number of tumor cells (84% of specimens had more than 30 tumor cells) and percentage of tumor DNA in area selected for molecular analysis (62% had >40% and 10% had 21-40%) PD-L1 assay was successfully performed in 28 out of 31 NSCLC cases (90%). Of those cases, 68% demonstrated positive expression. In adenocarcinoma cases, the specimen adequacy for molecular marker testing was 90%. The success rate in testing was 90% for EGFR and 86% for ALK. For ROS-1, the success rate for testing was 67% (14 out of 21) while 24% of the specimens (5 out of 21) were deemed to have adequate tumor tissue but experienced technical difficulty with the assay. There were no adverse events. CONCLUSIONS: EBUS-TBNA using 19-gauge needles can obtain a high number of tumor cells and has a high rate of success in performing assays of PD-L1, EGFR, and ALK in non-small cell lung cancer patients without an increase in adverse events. The success rate of ROS-1 testing was lower. CLINICAL IMPLICATIONS: EBUS-TBNA of mediastinal lymphadenopathy with 19-gauge needle can suffice as a less invasive means to collect tumor cells and determine molecular marker status in patients with lung cancer. Larger comparative trials are needed. DISCLOSURES: Consultant relationship with Olympus Please note: $5001 - $20000 Added 11/25/2018 by Alexander Chen, source=Web Response, value=Consulting fee Consultant relationship with Auris Please note: $1001 - $5000 Added 11/25/2018 by Alexander Chen, source=Web Response, value=Consulting fee Consultant relationship with Intuitive Surgical Please note: $1001 - $5000 Added 11/25/2018 by Alexander Chen, source=Web Response, value=Consulting fee Consultant relationship with Boston Scientific Please note: $1001 - $5000 Added 11/25/2018 by Alexander Chen, source=Web Response, value=Consulting fee Research relationship with Veran Medical Please note: $5001 - $20000 Added 03/14/2019 by Alexander Chen, source=Web Response, value=Grant/Research Owner/Founder relationship with Restore3D Please note: $5001 - $20000 Added 11/27/2018 by George Cheng, source=Web Response, value=Ownership interest Consultant relationship with Medtronic Please note: $1-$1000 Added 11/27/2018 by George Cheng, source=Web Response, value=Consulting fee Research relationship with Intuitive Surgical Please note: $20001 - $100000 Added 11/27/2018 by George Cheng, source=Web Response, value=Grant/Research Consultant relationship with Boston Scientific Please note: $1001 - $5000 Added 11/27/2018 by George Cheng, source=Web Response, value=Consulting fee Speaker/Speaker's Bureau relationship with Pinnacle Biologics Please note: $1-$1000 Added 11/27/2018 by George Cheng, source=Web Response, value=Honoraria Research relationship with Veran Please note: $1001 - $5000 Added 11/27/2018 by George Cheng, source=Web Response, value=Grant/Research Support No relevant relationships by Kevin Davidson, source=Web Response No relevant relationships by Coral Giovacchini, source=Web Response No relevant relationships by Claudia Jones, source=Web Response No relevant relationships by Rachel Jug, source=Web Response No relevant relationships by Kamran Mahmood, source=Web Response no disclosure on file for elizabeth pavlisko; no disclosure on file for Scott Shofer; No relevant relationships by Momen Wahidi, source=Web Response no disclosure on file for Cody Weimholt; No relevant relationships by Zhongren Zhou, source=Web Response