Utility of endobronchial ultrasound-guided-fine-needle aspiration and additional value of cell block in the diagnosis of mediastinal granulomatous lymphadenopathy.

Background: Endobronchial ultrasound-guided transbronchial fine-needle aspiration is a minimally invasive technique for diagnosis of mediastinal lesions. Although most studies have reported the utility of EBUS-FNA in malignancy, its use has been extended to the benign conditions as well.
Objective: To evaluate the diagnostic yield and cytologic accuracy of endobronchial ultrasound-guided transbronchial fine-needle aspiration (EBUS-FNA) in cases of clinically and radiologically suspected granulomatous diseases.
Patients and Method: From May 2010 to April 2015, 43 of 115 patients who underwent EBUS-FNA at one center for radiologically and clinically suspicious granulomatous lesions, and with no definite histological diagnosis, were included in this retrospective study.
Results: When the histological diagnosis was taken as the gold standard, the sensitivity of EBUS-FNA was 85% and specificity was 100% with the positive predictive value of 100. The combined diagnostic sensitivity of EBUS-FNA and transbronchial lung biopsy was 100%. In 4 cases, cell block provided an exclusive morphological diagnosis of sarcoidosis which was noncontributory by EBUS-FNA.
Conclusion: Our study supports the use of EBUS-FNA, by virtue of being a safe, minimally invasive, and an outpatient procedure, in the diagnosis of granulomatous mediastinal lymphadenopathy, thereby obviating more invasive testing in a significant number of patients. Also, cell block provides additional data in the diagnosis in these benign mediastinal diseases.