Primo Carnera (1906–1967), nicknamed the Ambling Alp, was an Italian professional boxer and wrestler who reigned as the boxing World Heavyweight Champion from 29 June 1933 to 14 June 1934. Maurice Tillet (1903–1954), Russian-born French professional wrestler, is better known by his ring name, the French Angel. Richard Kiel (1939–2014), actor, "Jaws" from two James Bond movies and Mr. Larson in Happy Gilmore
Pío Pico, the last Mexican Governor of California (1801–1894), manifested acromegaly without gigantism between at least 1847 and 1858. Some time after 1858, signs of the growth hormone-producing tumor disappeared along with all the secondary effects the tumor had caused in him. He looked normal in his 90s. His remarkable recovery is likely an example of spontaneous selective pituitary tumor apoplexy. Earl Nightingale (March 12, 1921 – March 25, 1989) was an American radio speaker and author, dealing mostly with the subjects of human character development, motivation, and meaningful existence. He was the voice during the early 1950s of Sky King, the hero of a radio adventure series, and was a WGN radio program host from 1950 to 1956. Nightingale was the author of The Strangest Secret, which economist Terry Savage has termed "…one of the great motivational books of all time." Nightingale’s daughter, Pamela, mentioned her father had acromegaly during a podcast about her father that aired in June 2022.
These tumors produce excessive growth hormone and compress surrounding brain tissues as they grow larger. In some cases, they may compress the optic nerves. Expansion of the tumor may cause headaches and visual disturbances. In addition, compression of the surrounding normal pituitary tissue can alter production of other hormones, leading to changes in menstruation and breast discharge in women and impotence in men because of reduced testosterone production.A marked variation in rates of GH production and the aggressiveness of the tumor occurs. Some adenomas grow slowly and symptoms of GH excess are often not noticed for many years. Other adenomas grow rapidly and invade surrounding brain areas or the sinuses, which are located near the pituitary. In general, younger people tend to have more aggressive tumors.Most pituitary tumors arise spontaneously and are not genetically inherited. Many pituitary tumors arise from a genetic alteration in a single pituitary cell that leads to increased cell division and tumor formation. This genetic change, or mutation, is not present at birth but is acquired during life. The mutation occurs in a gene that regulates the transmission of chemical signals within pituitary cells; it permanently switches on the signal that tells the cell to divide and secrete growth hormones. The events within the cell that cause disordered pituitary cell growth and GH oversecretion currently are the subject of intensive research.Pituitary adenomas and diffuse somatomammotroph hyperplasia may result from somatic mutations activating GNAS, which may be acquired or associated with McCune-Albright syndrome.