Pituitary-directed medical therapy in Cushing's disease.

Transsphenoidal surgery remains the first line therapy in Cushing's disease, but a large number of patients will not be cured or disease will recur over time. Repeat pituitary surgery, bilateral adrenalectomy, and radiation have limitations with respect to efficacy and/or side effects. Therefore, there is a clear need for an effective medical treatment. The studies reviewed here suggest a role for pituitary-directed therapies, applying multireceptor ligand somatostatin analogs like pasireotide or second-generation dopamine agonists. Retinoic acid has been also studied in a small prospective study. These compounds target ACTH-secretion at the pituitary level and possibly inhibit corticotrope proliferation. Specific side effects of these compounds need to be considered, especially when used as long-term therapy. These novel approaches could provide options for treatment of patients in whom surgery has failed or is not possible, and while awaiting effects of radiation therapy. Preoperative use to decrease cortisol excess, potentially reducing perioperative complications, needs to be further studied.