John is a 26-year-old man who begins to notice a progressive enlargement of feet, hands, cranium, nose, and lower jaw bone. His doctor recommends irradiation of the pituitary gland. What is the most likely diagnosis, and what caused this condition?
The diagnosis is acromegaly. The condition results from excess secretion of growth hormone from the pituitary gland post puberty and after the epiphyseal plates of the long bones has fused.