This low power microscopic image of fibrocystic changes shows broad areas of pink, uniform tissue to be present, which represents increased fibrous tissue. Fibrous tissue is composed of dense collagen fibers. Nearby are small round ducts, which are increased in size and show features of adenosis (meaning full of glands). The large spaces, known as cysts, filled with fluid, and often lined by cells resembling sweat glands. These smaller cysts may have a bluish color when viewed with the naked eye.