Antisecretory Effects of Gamma Knife Radiosurgery Gamma Knife Radiosurgery and Growth-hormone-secreting Pituitary Adenomas First-line treatment of acromegaly is trans-sphenoidal surgery,2 but the remission rate ranges

Pituitary adenomas are benign tumours that may induce clinical signs either by secreting hormones (growth hormone [GH], adrenocorticotropin hormone [ACTH] or prolactin [PRL]) or by local mass effect, particularly chiasmatic compression. Thus, the therapeutic algorithm is different whether the aim of the treatment is to control signs of hormone hypersecretion (for instance in a secreting microadenoma) or tumour volume (for instance in a large non-secreting pituitary adenoma). Trans-sphenoidal surgery is the treatment of choice for most pituitary adenomas; however, this surgical approach does not always allow definite remission and efficacious adjunctive treatment is often needed. Medical treatments have an inconstant effectiveness, and conventional radiotherapy, although highly effective, induces high rates of panhypopituitarism.1–4