<prompt> Commonest cause of blood discharge from the nipple isDuct carcinomaDuct papillomaChronic cystic mastitisCystosarcoma phyllodes  <response>: Duct papilloma is the Commonest cause of blood discharge from the nipple Duct papilloma are epithelium lined true polyps of breast lactiferous ducts it is usually single,from a single lactiferous duct it blocks the duct causing ductal dialatation ref ;page no;528 5th edition of SRB;S Manual of SURGERY 