title: Yield of EBUS-TBNA for the diagnosis of sarcoidosis: impact of operator and cytopathologist experience.
abstract: BACKGROUND
  Studies have reported a high diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the diagnosis of sarcoidosis. We sought to review the yield of EBUS-TBNA for the diagnosis of sarcoidosis at our institution over time, and examine factors that may influence this yield.
  
  
  METHODS
  Patients who underwent EBUS-TBNA for suspected sarcoidosis between December 2008 and November 2011 were identified. EBUS was performed without rapid on-site evaluation (ROSE) of samples. The final diagnosis was based on the results of all invasive diagnostic procedures and/or clinical follow-up. Logistic regression analysis was used to examine the effect of various factors on yield.
  
  
  RESULTS
  43 patients underwent 45 EBUS-TBNA procedures for suspected sarcoidosis. A total of 115 lymph nodes were sampled. The 21 G needle was used in 51% of procedures. The mean number of lymph node stations sampled was 2.6 (SD 0.7) and the mean number of needle passes per procedure was 7.8 (SD 2.0). Non-necrotising granulomatous inflammation was detected in EBUS-TBNA samples from 34/45 (76%) procedures. The overall diagnostic yield increased to 36/45 (80%) following a cytopathology review for this study. Needle gauge, number of lymph node stations sampled and number of needle passes were not associated with diagnostic yield. The yield of EBUS-TBNA increased significantly after the first 15 procedures performed for suspected sarcoidosis; the 2 additional cases diagnosed after the cytopathology review were part of this early experience.
  
  
  CONCLUSIONS
  EBUS-TBNA is a valuable technique for the diagnosis of sarcoidosis when performed without ROSE. The yield of the procedure improved significantly over time, based on operator and cytopathologist experience.
authors.affiliation: Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, McGill University Health Centre, Montreal, Quebec, Canada; Respiratory and Respiratory Critical Care Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand.
authors.forename: Asma
authors.initials: A
authors.lastname: Navasakulpong
authors.affiliation: Department of Pathology , McGill University and McGill University Health Centre , Montreal, Quebec , Canada.
authors.forename: Manon
authors.initials: M
authors.lastname: Auger
authors.affiliation: Respiratory Epidemiology and Clinical Research Unit , Montreal Chest Institute, McGill University Health Centre , Montreal, Quebec , Canada.
authors.forename: Anne V
authors.initials: AV
authors.lastname: Gonzalez
keywords: Bronchoscopy; Histology/Cytology; Sarcoidosis