Contribution of fine needle capillary sampling in patients undergoing endobronchial ultrasonography (EBUS), a randomized controlled trial

Purpose: There is still no standard method for sampling techniques performed with endobronchial ultrasound (EBUS). Therefore, in our study, we aimed to compare transbronchial needle aspiration (EBUS-TBNA) and fine needle capillary sampling (EBUS-TBNCS) methods in mediastinal lymph node sampling using EBUS in terms of adequacy, diagnosis, and duration Material and methods: Patients who underwent EBUS in our clinic between 2021 and 2024 to elucidate the etiology of mediastinal LAP were included in our prospective, single-blind, and randomized study. EBUS was performed on each lymph node using both methods, TBNA and TBNCS. Results: A total of 114 samples were taken from 79 patients with pathological lymph nodes. The mean age of the patients was 62.85 ± 11.27 years, and the age range was between 21 and 85 years. 65.8% of the patients were male and 34.2% were female. The most frequent sampling localization was found to be the 7th station (36.8%). There was no statistically significant difference between EBUS-TBNA and EBUS-TBNCS methods in terms of pathological adequacy in the samples taken with EBUS (p=0.219). In terms of pathological adequacy of the samples taken, 103 were sufficient for both, 5 were insufficient for both, and 6 were discordant; overall global agreement was 94.74%; Cohen's Kappa was 0.599, defining moderate agreement (94.74%; 95% CI (88.9-92.04), κ = 0.599). When evaluated diagnostically, 93 were diagnostic for both, 7 were non-diagnostic for both, and 3 were discordant; overall global agreement was 97.09%; Cohen's Kappa was 0.808, defining significant agreement (97.09%; 95% CI (91.72-99.40), κ = 0.808). In addition, there was no statistically significant difference between the methods diagnostically (p=1). Near perfect agreement was found in terms of the main diagnosis (κ=0.954, p<0.001). In terms of procedure times, the average EBUS-TBNA was 4.28 ± 0.86 minutes and the EBUS-TBNCS was 3.07 ± 0.68 minutes, with a statistically significant difference between them (p<0.001) Conclusion: TBNCS, when performed under EBUS guidance, is a more practical and equally effective technique due to its shorter duration and lack of need for additional equipment. Since it does not affect diagnostic outcomes and reduces procedural complexity, it can be preferred over the conventional method. Keywords: EBUS, Aspiration, Capillery sampling