Laparoscopic adrenalectomy (LA) is a preferred method for the removal of small adrenal masses. However, the role of LA for surgical treatment of large adrenal masses is less established. We evaluated the outcomes of LA for large (>/=5 cm) adrenal masses. We retrospectively reviewed 24 consecutive patients who underwent LA for large adrenal masses at a tertiary care university hospital. The average age of the 24 patients was 49 years, and each underwent laparoscopic resection of a large adrenal mass. All LAs were performed via a lateral transperitoneal approach. The average (+/- standard deviation) size of the masses was 6.8 +/- 1.5 cm (range, 5-11). Pathologic diagnoses included adrenal cortical adenoma (10 cases), pheochromocytoma ( 7), cyst/pseudocyst ( 3), myolipoma ( 2), and adrenal cortical hyperplasia ( 2). Statistical analysis was performed with a two-sample t test. The average operating time was 178 +/- 55 minutes (range, 120-300), and average blood loss was 87 +/- 69 mL (range, 20-300); the averages were nonsignificantly greater in the right LA group than in the left LA group (203 vs. 166 minutes, P = 0.89; 124 vs. 77 mL, P = 0.14). The average duration of nothing-by-mouth (NPO) status was 0.7 days (range, 0-4), and the average time until return to a regular diet was 1.74 +/- 0.9 days (range, 1-5). The average length of stay was 2.5 +/- 1.9 days (range, 1-10). One patient had a transient episode of pseudomembranous colitis. There were no conversions to open adrenalectomy and no major morbidities or mortalities. LA is safe and effective for surgical treatment of large adrenal masses. Both right and left large adrenal masses can be approached laparoscopically with equal success. The role of minimally invasive approaches to adrenal malignancies necessitates further investigation.