Acromegaly

Acromegaly is a rare, chronic, debilitating condition. Untreated, it causes significant morbidity and reduces life expectancy by about 10 years. The disease process is insidious, and early presenting features can be non-specific (e.g. sweating, fatigue). Physicians, dentists and surgeons should consider this diagnosis if any of the more classically recognized features is present (e.g. dental malocclusion, symptoms of median nerve entrapment, sleep apnoea, type 2 diabetes mellitus without a family history). This is important because surgery remains the only hope of cure, and surgical outcome varies widely with the size of the adenoma (≥90% for microadenomata versus 40-45% for macroadenomata, even lower for tumours invading local structures), which is in turn is related to disease duration. The diagnosis of acromegaly is based on three key findings: clinical features, elevated age-adjusted serum insulin-like growth factor 1 concentration and serum growth hormone nadir >0.3 micrograms/litre following a 75 g oral glucose challenge. After biochemical confirmation of the disorder, magnetic resonance imaging of the pituitary is performed to assess the size and regional anatomy in anticipation of future surgery. Medical control of acromegaly has improved significantly in recent years, with the introduction of long-acting somatostatin analogues and the growth hormone receptor antagonist pegvisomant. Radiation therapy is a potential adjuvant therapy for patients with residual disease, but can take 5-10 years to have its full effect.