Transsphenoidal surgery is the initial treatment of choice for most patients with proved or highly suspected Cushing’s disease. Published reports demonstrate that at experienced centers, such as the California Center for Pituitary Disorders at UCSF, remission following surgery can be expected in 80 to 90% of patients with microadenomas and 50 to 60% of patients with macroadenomas. Recurrent hypercortisolism can be expected in approximately 10% of patients with microadenomas and 30% of patients with macroadenomas who enter remission after surgery.