[Acromegaly--diagnosis and treatment]

Acromegaly is a rare but clinically important disease caused by growth hormone hypersecretion, usually from a pituitary adenoma. The condition is associated with increased morbidity and mortality.

The prevalence of acromegaly is estimated to be 4-6 cases per million per year. The diagnosis is based on glucose-suppressed plasma growth hormone. When the diagnosis is confirmed, MR imaging of the pituitary gland is performed.

Standard treatment is transsphenoidal microsurgery; however, radicality is often difficult because of extensive tumour growth. Preoperative administration of somatostatin analogues may improve the surgical outcome.

We have initiated a randomized, prospective study to elucidate this adjuvant treatment. Somatostatin analouges are required in the case of postoperative activity. This treatment is without tachyphylaxis and has few side effects. Alternatively, dopamine agonists such as bromocriptine can be used, especially in mixed tumours coproducing prolactin. Newer, more specific dopamine agonists are currently being evaluated. Radiation therapy may be required in large, unresectable tumours, but the effects are slow-acting, and almost all patients develop hypopituitarism. Gamma knife radiosurgery seems promising for stopping tumour growth as well as for decreasing excessive hormone production. However long-time follow-up results are so far lacking.