Acromegaly is gigantism that arrives after the body has stopped growing
Flood a child's body with growth hormone and the result is extreme height. Do it after the growth plates have closed and bones can no longer lengthen, so hands, feet, jaw and brow thicken instead. That adult form, acromegaly, usually traces back to a single benign tumour in the pituitary gland.
About 98 per cent of cases come from a pituitary adenoma, a noncancerous growth that pumps out excess growth hormone. Most arise from a mutation acquired during life in one pituitary cell, which locks on the internal signal telling it to divide and secrete. As the tumour enlarges it can press on the optic nerves, causing headaches and vision trouble, and squeeze normal pituitary tissue, disturbing other hormones. Rarely, tumours in the pancreas, lungs or adrenal glands are responsible, usually by releasing a hormone that drives the pituitary.
Changes creep in slowly, which is why diagnosis often lags years behind onset. Typical signs include enlarged hands and feet, a jutting jaw and brow, a deeper voice, thicker skin and aching joints. Doctors confirm it by measuring growth hormone after a sugary drink, or by testing a related blood marker, then image the pituitary. The condition affects roughly 6 people in 100,000, men and women equally, and is most often found in middle age. Nicolas Saucerotte described it in 1772; the name joins Greek words for extremity and large.
Surgery is usually the first choice, most often through the nostrils, and small tumours are the likeliest to be cured. Drugs that mimic the hormone somatostatin, a blocker of the growth hormone receptor called pegvisomant, and radiation are further options. Untreated, acromegaly shortens life by around 10 years, while successful early treatment brings life expectancy in line with the general population. Some problems persist: sleep apnoea, present in about 70 per cent of cases, tends not to resolve.
The heart bears much of the burden. A review in Endocrine Reviews identifies cardiovascular disease as a leading cause of reduced survival. One surprise comes from a meta-analysis of 9 observational studies covering 190 patients: people with acromegaly had significantly less liver fat than matched controls, especially when the disease was active, while liver stiffness showed no clear difference.
Source: Acromegaly
