Objective: To evaluate the efficacy of Endobronchial ultrasound guided-transbronchial needle aspiration (EBUS-TBNA) for biopsy specimens with adequate evaluable lymphocytes and mediastinal lymph node diagnosis.
Material and Method: Prospective cohort study. Over 18 year old patients with mediastinal or hilar lymphadenopathy, with short axis diameter greater than 10 mm on chest CT were indicated to undergo EBUS-TBNA. When a node was detected, an aspiration was performed under ultrasound guided. The primary end point was the percentage of biopsy specimen with adequate evaluable lymphocytes that had been evaluated by cytopathologist. Secondary end point was the percentage of EBUS-TBNA diagnosis result.
Results: 82 patients with mediastinal or hilar lymphadenopathy underwent EBUS-TBNA. Average size of lymph node was 1.57 x 1.49 cm. The overall of the diagnostic accuracy was a percentage of biopsy specimen with adequate evaluable lymphocytes as 97.7%. For mediastinal lymph node diagnosis, the cytological evaluation demonstrated that the positive for malignancy, atypical or suspicious for malignancy, negative for malignancy and non-diagnosis were 37.2%, 9.3%, 2.3% and 51.2%, respectively. In case of positive for malignancy, non-small cell carcinoma, adenocarcinoma, bronchoalveolar cell carcinoma and small cell carcinoma were found 62.5%, 15.6%, 3.1% and 18.8% , respectively. Additionally, the pathological examination showed that positive for malignancy, atypical or suspicious for malignancy, negative for malignancy and non-diagnosis were found 35.4%, 7.3%, 3.6% and 53.7%, respectively. There were no complications during all of the procedures.
Conclusion: High percentage of biopsy specimen with adequate evaluable lymphocytes can be obtained in EBUS-TBNA. This finding suggested that this method should be considered for mediastinal lymph node diagnosis.

Keywords: Endobronchial ultrasound guided-transbronchial needle aspiration (EBUS-TBNA)