EUS-FNA of the left adrenal gland-diagnostic yield and complications

Background: There are limited published data on the clinical utility and safety of endososcopic ultrasound (EUS)-guided fine needle aspiration (FNA) of the left adrenal gland. This study examined the diagnostic yield and safety of EUS-FNA of left adrenal masses at a single referral centre. Methods: Patients with an enlarged left adrenal gland diagnosed on abdominal imaging or during tumor staging and who were referred for EUS-guided FNA from Nov 1996 to May 2005 were included. The diagnostic yield, complication rate and features predictive of malignancy were examined. Results: Thirty-six consecutive patients were evaluated. EUS-FNA was not performed in 2 patients due to suspected phaeochromocytoma. Thirty-four patients (24 male, 10 female; mean age 67 years) underwent EUS-FNA and were analyzed. The indications were isolated left adrenal mass (9) and possible left adrenal metastases in suspected (6) or confirmed malignancies (19). Adequate tissue specimens were obtained in all cases. The median number of needle passes was 1 (1–2). There were no procedure-related complications. Among patients with confirmed underlying malignancies, adrenal metastases were diagnosed in 14/19 and adrenal adenoma in 5/19. Among isolated left adrenal masses, adenoma was present in 8/9, with one case of adrenal carcinoma. Features predictive of malignant cytology were larger size (38.2 vs. 17.9mm; p=0.01), loss of normal adrenal outline (OR 11.4; 95% CI 1.6–83.3) and presence of extra-adrenal malignancies (OR 10.3; 95% CI 1.5–71.4). Conclusion: EUS-guided FNA is a safe and highly accurate method to determine the nature of an isolated left adrenal mass and to confirm adrenal metastases. A larger size, loss of normal adrenal outline and presence of extra-adrenal malignancies are suggestive of a malignant adrenal mass, but FNA is required for definitive diagnosis.