EUS-B-FNA vs conventional EUS-FNA for left adrenal gland analysis in lung cancer patients.

Introduction: In patients with lung cancer, left adrenal glands (LAG) suspected for distant metastases (M1b) based on imaging require further evaluation for a definitive diagnosis. Tissue acquisition is regularly performed using conventional EUS-FNA. The aim of this study was to investigate the success rate of endoscopic ultrasound guided fine-needle aspiration using the EBUS scope (EUS-B-FNA) for LAG analysis.

Methods: This is a prospective multicenter study in consecutive patients with (suspected) lung cancer and suspected mediastinal and LAG metastases. Following complete mediastinal staging using the EBUS scope (EBUS+EUS-B), the LAG was evaluated and sampled by both EUS-B (experimental procedure) and conventional EUS (current standard of care).

Results: The success rate for LAG analysis (visualized, sampled and adequate tissue obtained) was 89% (39/44; 95% CI 76-95%) for EUS-B-FNA, and 93% (41/44; 95%CI 82-98%) for EUS-FNA. In the absence of metastases at EUS-B and/or EUS, surgical verification of the LAG or 6 months clinical and radiological follow-up was obtained, but missing for 5 patients. The prevalence of LAG metastases was 54% (21/39). In patients in whom LAG was seen and sampled, sensitivity for LAG metastases was at least 87% (95%CI 65-97%) for EUS-B, and at least 83% (95%CI 62-95%) for conventional EUS.

Conclusion: LAG analysis by EUS-B shows a similar high success rate in comparison to conventional EUS.

Implication: Both a mediastinal nodal and LAG evaluation can be adequately performed with just an EBUS scope and single endoscopist. This staging strategy is likely to reduce patient-burden and costs.