Acromegaly surgery

Discuss the role of surgery and radiation therapy for patients with acromegaly. 

Somatostatin analogs are the mainstay of pharmacotherapy for the treatment of acromegaly when surgery and radiation are contraindicated or have failed. 

Pegvisomant is a growth hormone receptor antagonist registered for the treatment of patients with acromegaly who had insufficient benefit from surgery or radiation. 

Acromegaly is almost always caused by a pimitary growth hormone (GH)-secreting adenoma, and transsphenoidal surgery is normally considered to be the first treatment of choice. A number of patients are not cured by surgery, however, and GH hypersecretion is nowadays treated actively, because of its known associated excess mortality. 

A dopamine agonist alone or in combination with pituitary surgery, radiation therapy, or octreotide administration can be used to treat acromegaly. The doses required are higher than those used to treat hyperprolactinemia. For example, patients with acromegaly require 20-30 mg/d of bromocriptine and seldom respond adequately to bromocriptine alone unless the pituitary tumor secretes prolactin as well as GH. 

In acromegaly, excess growth hormone causes diabetes, hypertension and arthritis. The former two lead to a 2-fold excess in cardiovascular mortality. Surgery is the treatment of choice. Growth hormone secretion is reduced by octreotide and other somatostatin analogues and to a lesser degree by bromocriptine (see Index). 

Pharmacologic therapy for acromegaly should be considered when surgery and irradiation are contraindicated, when rapid control of symptoms is needed, or when other treatments have failed to normalize growth hormone (GH) and insulin-like growth factor-1 (IGF-I) concentrations. 

Because neither radiation therapy nor surgery will cure all patients with acromegaly, adjuvant drug therapy is often needed to control symptoms. ... 

Some clinicians advocate the use of somatostatin analogues for primary therapy of acromegaly in place of surgery. However, others believe that sufficient long-term safety and efficacy data are lacking. 

Geelhoed-Duijvestijn, PJI.L.M., Bussemaker, J.K., Roelfsema, F., 1989, Changes in basal and stimulated TSH and other parameters of thyroid function in acromegaly after transsphenoidal surgery, Acta Endocrinologica 121 207. 

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