Usefulness of combined endobronchial and endoscopic ultrasound-guided needle aspiration in the diagnosis of sarcoidosis: a prospective multicenter trial.

INTRODUCTION: Needle biopsy of enlarged lymph nodes is an accepted method for the diagnostic workup of sarcoidosis, but the optimal endosonography­guided approach is yet to be determined. OBJECTIVES: The aim of our study was to assess the relative diagnostic yield of combined ultrasound­guided needle aspiration (CUS­b­NA), which includes endobronchial ultrasound­guided transbronchial needle aspiration (EBUS­TBNA) with endoscopic ultrasound fine­needle aspiration (EUS­b­FNA), as well as the role of the cell block (CB) technique and lymph node localization in the diagnostic workup of sarcoidosis. PATIENTS AND METHODS: This was a prospective multicenter study including consecutive patients with clinical suspicion of stage I or II sarcoidosis. CUS­b­NA with smears and CB technique were performed in the whole study group. If a biopsy result was not conclusive, an invasive diagnostic workup and a 6-month follow­up were scheduled. RESULTS: Out of 77 screened patients, 54 signed written consent and 50 were enrolled for the final analysis. The overall sensitivity of EBUS­TBNA, EUS­b­FNA, and CUS­b­NA was 76.6%, 70.2%, and 91.7%, respectively. There were no differences between EBUS­TBNA and EUS­b­FNA (P = 0.52) but CUS­b­NA had a higher diagnostic yield (P = 0.005 and P = 0.001, respectively). Adding the CB method to smear technique (P = 0.008) and biopsy of the subcarinal lymph nodes increased the diagnostic yield (P = 0.001).  Conclusions: The diagnostic yield of CUS­b­NA is higher than that of endosonographic techniques alone in the diagnostic workup of stage I and II sarcoidosis. The preparation of cytological material including CB and the choice of the subcarinal lymph node station for the biopsy increase the diagnostic efficacy.