World's Tallest Man to Have Surgery to Stop Growth

Sultan Kosen will have surgery Thursday to stop the abnormal growth spurts that have made him the tallest man in the world.

The 27-year-old from Turkey is more than 8 feet tall as a result of a rare hormonal condition called acromegaly, which causes the pituitary gland to produce too much growth hormone, usually as a result of a noncancerous tumor on the pituitary gland.

SLIDESHOW: World's Tallest Man

“He’s a charming individual,” said Dr. Jason Sheehan, associate professor of neurosurgery at the University of Virginia. “His condition has gotten to an extreme point whereby he is the tallest man in the world. Typically we’re able to catch patients and treat them well before they get to the extent that he has.”

Acromegaly causes the skeleton and internal organs to grow disproportionately. When the organs that also respond to growth hormone, like the kidneys, intestines and the heart, become enlarged, they become weakened. Patients typically also have deep voices and enlarged tongues, making it difficult to swallow.

Two previous surgeries and radiation therapy failed to remove Kosen's tumor. Thursday, Kosen will have gamma-knife radiosurgery at the University of Virginia, which Sheehan called the appropriate next step.

“We’re performing gamma-knife radiosurgery, where we deliver high intensity radiation to the tumor with the hope of shutting that tumor down: one to stop if from growing itself; and two to suppress its overproduction hormone that’s causing all the problems that he’s experienced,” he said.

Typically, this surgery will lead to a cure in six to 12 months, Sheehan said.Without effective treatment, patients with acromegaly have a substantially shorter life expectancy. They also have greater risk of developing cancer.

"We’re hoping that we can start him down the path to achieving a cure for his condition in the next 6 to 12 months," Sheehan said.