EBUS versus EUS-B for diagnosing sarcoidosis: The International Sarcoidosis Assessment (ISA) randomized clinical trial

Background and objective: Endosonography with intrathoracic nodal sampling is proposed as the single test with the highest granuloma detection rate in suspected sarcoidosis stage I/II. However, most studies have been performed in limited geographical regions. Studies suggest that oesophageal endosonographic nodal sampling has higher diagnostic yield than endobronchial endosonographic nodal sampling, but a head-to-head comparison of both routes has never been performed.Methods: Global (14 hospitals, nine countries, four continents) randomized clinical trial was conducted in consecutive patients with suspected sarcoidosis stage I/II presenting between May 2015 and August 2017. Using an endobronchial ultrasound (EBUS) scope, patients were randomized to EBUS or endoscopic ultrasound (EUS)-B-guided nodal sampling, and to 22- or 25-G ProCore needle aspiration (2 x 2 factorial design). Granuloma detection rate was the primary study endpoint. Final diagnosis was based on cytology/pathology outcomes and clinical/radiological follow-up at 6 months.Results: A total of 358 patients were randomized: 185 patients to EBUS-transbronchial needle aspiration (EBUS-TBNA) and 173 to EUS-B-fine-needle aspiration (FNA). Final diagnosis was sarcoidosis in 306 patients (86%). Granuloma detection rate was 70% (130/185; 95% CI, 63-76) for EBUS-TBNA and 68% (118/173; 95% CI, 61-75) for EUS-B-FNA (p = 0.67). Sensitivity for diagnosing sarcoidosis was 78% (129/165; 95% CI, 71-84) for EBUS-TBNA and 82% (115/141; 95% CI, 74-87) for EUS-B-FNA (p = 0.46). There was no significant difference between the two needle types in granuloma detection rate or sensitivity.Conclusion: Granuloma detection rate of mediastinal/hilar nodes by endosonography in patients with suspected sarcoidosis stage I/II is high and similar for EBUS and EUS-B. These findings imply that both diagnostic tests can be safely and universally used in suspected sarcoidosis patients.