ObjectiveTo investigate whether liquid-based cytology (LBC) can improve diagnostic value of cytological assessment of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). MethodsA cohort of 600 cases who underwent EBUS-TBNA from June 2012 to September 2013 was enrolled in this prospective study in West China Hospital. EBUS-TBNA was carried out under local anesthesia and moderate sedation. The procedure was performed with echobronchoscopes. Histological tissues were stained with hematoxylin and eosin for further study. Additional immunohistological analysis was performed for establishing a reliable diagnosis as necessary. Aspirates were smeared on glass slides and separate aspirates were processed by the monolayer SurePath method. ResultsIn total, 480 cases of malignant tumors and 120 cases of benign lesions were confirmed by histological examination. The sensitivity of SurePath liquid-based preparations and conventional smears was 82.1% and 56.0%, and the specificity was 87.5% and 82.5%, respectively. The combined specificity was 100.0%. The positive predictive value of two methods combined was 96.3% and 92.8%, whereas the negative predictive value was 54.9% and 31.9%, respectively. The difference between the two methods was significant (P < 0.05). ConclusionsLBC preparation can improve cytological assessment of EBUS-TBNA. Histological study is necessary when the cytological diagnosis is obscure.