The treatment of choice for ACTH-producing pituitary adenoma is selective transsphenoidal adenomectomy. The remission rate after transsphenidal surgical intervention for Cushings disease ranges from 69 to 98% (average 83%). If the first pituitary surgical intervention fails, the following questions should be answered: i) Is the localization diagnosis correct without doubt (pituitary or ectopic source of ACTH- overproduction)? ii) Is it reasonable to recommend repeat pituitary surgery? The answers to these questions depend on the results of inferior petrosal sinus sampling (IPSS) and histology.
If the diagnosis of ACTH-producing pituitary adenoma is without doubt, in cases of microadenomas (both visible and invisible on MRI) repeat pituitary surgical intervention seems to be the best choice. In the best hands, remission after repeat surgery may occur in 5060% of patients contrary to the 7590% remission rate of the first surgery. Regarding the extent of repeat pituitary surgery, selective adenomectomy, hemihypophysectomy or total hypophysectomy may be performed. Scarce literature data suggest that IPSS performed before reoperation has much inferior diagnostic information than the sampling performed before the first intervention. This observation may probably be explained by altered anatomic situation and venous drainage caused by the initial surgery.
If repeat pituitary surgery does not achieve remission, then radiosurgery or stereotactic radiotherapy, bilateral adrenalectomy, and/or medical therapy are the therapeutic options. Medical therapy for the treatment of Cushings disease may target the ACTH secretion of the pituitary tumor (cabergoline, pasireotide) or block the steroid biosynthesis of the adrenals (ketoconazole, metyrapone, mitotane).
Bilateral laparoscopic adrenalectomy may be a therapeutic option in most severely hypercortisolemic patients. Nelsons syndrome is potentially the most severe complication of bilateral adrenalectomy developing in 2030% of adrenalectomized patients. The newest series of Nelsons syndrome represent that the modern Nelsons syndrome is different from the entity originally described.
Declaration of interest: The author declares that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.