The microcentrifuge tube cell block technique improves mediastinal mass and lymphadenopathy diagnosis and cellularity yield in endobronchial ultrasound transbronchial needle aspiration specimens.

<bold>Background:</bold> Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a technique for collecting samples from mediastinal regions for cell block method. The collection of cell blocks specimens differed between laboratories and lack of standardization. The purpose of the study was to compare the efficiency of microcentrifuge tube cell block (MCT-CB) and tissue coagulum cell block (TCC-CB) in diagnosing yield. <bold>Objectives:</bold> To evaluate the diagnostic yields and the cellularity of cell block using the MCT-CB in comparison to TCC-CB. <bold>Methods:</bold> We conducted a randomized crossover trial to study the effectiveness of cell blocks with the TCC-CB and the MCT-CB. Three experienced bronchoscopists performed the EBUS TBNA and two pathologists assessed the cell block specimens. The primary outcomes are cellularity and diagnostic yield of cell blocks. <bold>Results:</bold> A total of 55 mediastinal lymph nodes were collected from 37 patients. The MCT-CB group achieved a yield of 89.09%. The TCC-CB yielded 85.45%. There was no statistically significant difference in diagnosis yield between the two groups (p=0.567). The sensitivity of MCT-CB and TCC-CB were 85.7% and 81%, respectively. In term of cellularity, 14 lymph nodes (25.45%) having equal cellularity, 23 lymph nodes (41.82%) showing higher cellularity in the MC-CB group, and 18 lymph nodes (32.73%) exhibiting higher cellularity in the tissue filter CB group. <bold>Conclusions:</bold> The MCT-CB employed in EBUS-TBNA has comparable cellularity and diagnostic yield as the TCC-CB. However, MCT-CB has the ability to increase cellularity.