Comparison of endobronchial ultrasound-guided transbronchial needle aspiration with stylet retracted partially versus completely for molecular testing

Background:Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is considered to be the initial diagnostic modality for most patients with lung cancer. However the optimal technique for maximizing yield continues to vary in the real-world setting.Objectives:To evaluate the diagnostic yield of EBUS-TBNA with capillary sampling compared with complete stylet removal for molecular testing.Methods:Retrospective study data from patients between January to May 2017 with indication of EBUS-TBNA whom ancillary testing that is next-generation sequencing anaplastic lymphoma kinase (ALK) and programed death ligand-1 (PD-L1) expression was reviewed. The yield of 2 techniques stylet retracted halfway (group 1) versus complete retraction (group 2) was compared.Results:A total of 24/27 (88.88%) samples were adequate for next-generation sequencing analysis in group 1 and 21/23 (91.30%) in group 2. For other molecular analyses 24/27 (88.88%) samples in group 1 and 20/23 (86.95%) samples in group 2 were adequate for ALK analysis. 23/27 (85.18%) samples for group 1 and 20/23 (86.95%) samples for group 2 were adequate for PD-L1 analysis. Positive expression of PD-L1>50% was achieved in 9/23 (39.13%) of group 1 and 5/20 (25%) of group 2. There was no statistical difference in the yield between the 2 groups.Conclusion:EBUS-TBNA using either capillary sampling or complete stylet removal are effective and has a high proportion of satisfactory results for ancillary testing.