Acromegaly is a hormonal disorder in which there is an overproduction of growth hormone.
If the disorder begins in puberty, it is called gigantism.
The tumor produces excess growth hormone, and as it grows it presses on the brain tissue around it.

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Most of these tumors occur spontaneously and are not genetically inherited.
Other tumors, especially in younger people, grow quickly and produce a lot of growth hormone.
If the tumor grows in childhood, gigantism results from abnormal bone growth.
The young adult grows extremely tall (in one case, to 8 feet 9 inches tall).
High levels of IGF-I usually indicate acromegaly.
They found that resection of at least 75% of the hormone-secreting tumor enhanced the response to medication.
The research was published in the January 2006 issue ofJournal of Clinical Endocrinology & Metabolism.
“Acromegaly: A new therapy.
“Cancer Control: Journal of the Moffitt Cancer Center9(2002).