EMPTY SELLA IN A PATIENT WITH CLINICAL AND BIOCHEMICAL DIAGNOSIS OF ACROMEGALY

Acromegaly is an acquired disorder related to excessive production of growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Empty sella (ES) is an anatomical condition of sella turcica that is partially or completely filled with cerebrospinal fluid mainly due to intrasellar herniation of subarachnoid space. Here, we describe a patient who presented with clinical and biochemical features of acromegaly and who had an ES on pituitary magnetic resonance imaging (MRI).

A 73-year-old male patient was consulted in our clinic because of the acromegalic phenotype while planning for colorectal adenocarcinoma surgery. The patient noticed gradual enlarging of his hands, feet and nose for 30 years, but never consulted to any clinician for this reason. Serum GH was 20.6 ng/mL (normal <3 ng/mL) and IGF-1 was 531 ng/mL (normal, 69-200 ng/ml). An oral glucose tolerance test showed no suppression of GH values. T1-weighted MRI revealed an ES. 18F-FDG PET/CT and Ga-DOTATADE PET/CT did not show any finding consistent with ectopic GH secretion. Growth hormone releasing hormone (GHRH) was within the normal range (<100mg/dL). He was treated with long-acting octreotide 20 mg per 28 days. At the 6^th month of treatment, serum GH and IGF-1 levels were decreased to 5.45 ng/mL and 274 ng/mL, respectively.

The mechanism underlying the association of acromegaly and ES remains unclear. Apoplexy on existing pituitary adenoma and then formation of necrosis can proceed to ES. Since our patient did not have a history of pituitary apoplexy and we could not find any reason for secondary ES, we considered primary ES.