Pituitary surgery beyond the sella

Abstract

Pituitary tumors are frequently occurring neoplasms, encompassing 10–15 % of all intracranial malignancies in surgical material and being found in up to 27 % of unselected autopsies [ 1 ]. They present with a broad spectrum of biological features: although almost invariably benign (adenomas), up to 20 % of pituitary tumors exhibit invasive behavior. The exceedingly rare pituitary carcinomas are histologically indistinguishable from adenomas, distant metastasis being the sole diagnostic criterion [ 2 ]. The treatment of pituitary tumors is based on their functional characteristics. Prolactin- secreting adenomas respond very well to medical treatment with dopamine agonists, which is the fi rst-line therapy of choice for such tumors. For GH-secreting adenomas causing acromegaly and ACTHsecreting tumors causing Cushing‘s disease, surgery is the fi rst line of treatment. Nonsecreting pituitary adenomas, especially macroadenomas (>1 cm) leading to visual loss due to optic chiasm compression, are treated surgically [ 3 ]. Classically, most pituitary tumors have been removed under microscopic visualization, through any of the variations (either sublabial or transnasal) of the transsphenoidal route. However, tumors with large suprasellar extension or those exhibiting lateral growth, whether suprasellar or into the cavernous sinus, could only be removed through transcranial approaches.