Ectopic prolactinoma within the sphenoidal sinus associated with empty sella

Abstract

Background:Pituitary adenomas are a common cause of endocrinal dysfunction, which comprise 10–20% of all intracranial tumors. Although almost all of them arise within the sella turcica, there are some rare cases in which a pituitary adenoma is located outside the intrasellar region, so it is defined as an ectopic pituitary adenoma (EPA).Case Description:We described a case of a 31-year-old male with a serum prolactin (PRL) value of 240 ng/ml Magnetic resonance imaging (MRI) showed a space-occupying mass within the sphenoid sinus (SS) which partially enhanced by gadolinium. MRI did not reveal any sellar floor defect and an empty sella was detected. As dopamine agonist treatment had failed in lowering the serum PRL level, he underwent surgical treatment. A transsphenoidal approach without opening the sellar floor was performed using an operating microscope and the lesion within the SS was completely removed.Conclusion:Although intrasphenoidal EPAs are rare findings, the presence of an endocrine disorder related to pituitary hormones, and a space-occupying mass within the SS associated with either a normal sellar pituitary gland or an empty sella must lead us to suspect this diagnosis.

Ectopic Pituitary Adenome of the Sphenoid Sinus. Case Report

“…The majority of the intracranial extrasellar EPAs are located in the suprasellar region (approximately 33%), usually contiguous with the pituitary stalk (28,36). Other less common sites are parasellar region, interpeduncular region, hypothalamus region, third ventricle, cavernous sinus (11,36,37).…”

Three cases of ectopic sphenoid sinus pituitary adenoma

“…It is hypothesized that neoplastic transformation occurs within the ectopic pituitary tissue located along the path of migration of Rathke's pouch, that is in the craniopharyngeal canal, or in the adjacent area [2,4,10,15,17,19]. Most frequently this tissue may be found in the sphenoid sinus, and then is called 'ectopic intrasphenoid hypophysis' [7,18].…”

“…Initial intrasellar localization of a pituitary adenoma with a following localized or diffuse destruction of sellar floor and extension into the sphenoid sinus -grade 3 and 4 in modified Hardy's system -is expected in 35% and 10% of cases, respectively [13]. Although MRI may help to confirm the integrity of sellar dura and sellar floor [4,10,12,19], the gold standard is an intraoperative verification [2,5,6,[9][10][11]15]. In case of bone erosion of sphenoid, the evidence of ESSPA seems less justifiable.…”

“…Currently, there is no established treatment for ESSPA [2]. Thompson et al postulated that surgical removal is a treatment of choice independently of hormone test results [17].…”

“…They are either characterized by well-defined radiological margins [17,19] or described as bone invading expansile lesions [4,15]. They originate from embryolo gic remnants of Rathke's pouch, which prematurely terminated their migration to the pituitary fossa [2,4,10,15,17,19].…”