Endocrine Abstracts

Background: Ectopic pituitary adenomas are defined by the presence of adenomatous pituitary tissue outside the sella and distinctly separate from the pituitary gland. Ectopic ACTH-secreting pituitary adenomas (EAPAs) are a rare cause of Cushing’s syndrome. Detecting these radiologically can prove difficult, in part, due to their typically small size and unpredictable anatomical location.

Aim: We reviewed the current literature on all previously reported EAPAs within the sphenoid sinus.

Results: Twenty cases of EAPAs have been reported in the literature to date. In most cases, ectopic ACTH pituitary adenomas within the sphenoid sinus will manifest with symptoms of hormonal excess, have an obvious sphenoid sinus mass on pre-operative imaging and will demonstrate resolution of hypercortisolism after surgical excision if located and removed.

Conclusions: In ACTH-dependent Cushing’s syndrome, if, despite comprehensive testing, the source of excess ACTH remains occult (including negative work up for ectopic ACTH syndrome) thought should be given to the possibility of the patient harbouring an EAPA. Careful review of the neuroimaging to identify potential lesions, especially when pituitary imaging is not conclusive, is imperative. In the context of negative ‘MR’ imaging, the presence of EAPAs should be considered. Appropriate investigation and resection of such lesions may prevent unwarranted hypophysectomy, radiotherapy and/or adrenalectomy and result in long term and persistent remission.