Gynecomastia is a condition that affects men and results in enlarged breast glands in boys or men. Gynecomastia is a condition in which males develop enlargement of the breast. This is quite common in adolescents and is often first noted at the onset of puberty. Gynecomastia affects an estimated 40% to 60% of men. The procedure removes fat and or glandular tissue from the breasts, and in extreme cases removes excess skin, resulting in a chest that is flatter, firmer, and better contoured.