With the popularity of medical checkups, more and more people are being found to have adrenal masses. Most of the masses are within 1-2 cm in diameter. However, a very small number of masses are very large, even reaching 10 cm or more. Adrenal masses are divided into two parts: functional and non-functional masses. Functional masses include primary aldosteronism, Cushing’s syndrome, and pheochromocytoma. Generally speaking, functional tumors require surgery, as do nonfunctional tumors over 3 cm.