Introduction
Ectopic pituitary adenomas (EPAs) are isolated adenomas located outside the sella turcica with a normal intrasellar pituitary gland. EPAs are thought to be extremely rare tumours [1]. The location of EPAs can vary, with approximately 60% of reported cases found in the sphenoid sinus and suprasellar region, 30% in the clivus, nasal cavity, parasellar region, cavernous sinus, and sphenoid wing [2]. The origin of EPAs can take one of three forms, with the most common being adenomas derived from residual cells of Rathke’s pouch which persist along the developmental pathway of the anterior pituitary gland. Clinical manifestations of EPAs usually depend on hormonal activity and involvement of adjacent structures. For example, tumours extending into the cavernous sinus or clivus can compress cranial nerves and cause visual disturbances and facial paresthesia, while sphenoid sinus EPA can result in headache, nasal obstruction and CSF leak [2]. The diagnosis and management of EPAs can be challenging and usually requires strong clinical suspicion along with magnetic resonance imaging (MRI) findings, including normal pituitary gland, and is confirmed by pathological studies. Computerized Tomograph (CT) can also provide useful information such as invasion of the sphenoid sinus, and therefore helps plan the endoscopic trans-sphenodial surgery, which is considered the most appropriate management approach [3, 4]. In this case, we present a clival ectopic pituitary prolactinoma.