Papilloma
Ductal papillomas or Intraductal papillomas: may be single or multiple and are very common aberrations of involution. They are wart like masses that grow within the duct, usually close to the nipple. Sometimes the papilloma may ooze clear or bloody discharge expressed from the nipple. They are usually 1-2cm in size but can be larger. It may be easier to remove one large area if multiple masses are present. The key point to note is that these lumps are non-cancerous