Pituitary adenomas

Abstract

Despite characteristic symptoms the diagnosis of clinically relevant pituitary adenomas is often delayed until an advanced stage due to the rarity of the disease. The typical clinical manifestations are presented in this review article. The recent discovery of the USP8 mutation in Cushing's disease and of X‑linked acrogigantism (X-LAG) syndrome in early onset gigantism were milestones in the search for the molecular etiology of pituitary adenomas. The triad of endocrinological, radiological and ophthalmological diagnostics are the main pillars for the diagnostic work-up of pituitary adenomas. The standard treatment modalities, which include surgery, medical treatment and irradiation, have been further developed and refined. For transsphenoidal excision of pituitary adenomas, microsurgery and endoscopy are two equivalent surgical techniques with relatively few complications. Surgery represents the first-line treatment of pituitary adenomas. Prolactinomas are an exception as the medical treatment with dopamine agonists is highly efficient. Nowadays, new medical treatment options are available for acromegaly and Cushing's disease and are used for second-line treatment. The alkylating chemotherapeutic agent temozolomide is used for the first-line chemotherapy of rare aggressively growing pituitary adenomas. Irradiation is indicated if surgical and medical treatment options are insufficiently successful. Stereotactic one-stage irradiation (radiosurgery) is especially suitable for well-demarcated invasive residual or recurrent adenomas in the cavernous sinus. A new development is hypofractionated radiosurgery for protection of structures at risk. Fractionated irradiation is necessary with large radiation volumes and for pituitary adenomas with a close proximity to the optic tract.