Intraductal papilloma is a small, benign (non-cancerous) tumor that grows within a milk duct of the breast. Intraductal papilloma occurs most frequently in women between the ages 35-55. The causes and risk factors are unknown. Symptoms can include:

  • Breast pain
  • Nipple discharge, sometimes bloody, from one breast only
  • Staining may be noticed inside the bra and/or clothing
  • Breast lump
  • Breast enlargement

Intraductal papilloma is the most common cause of spontaneous nipple discharge from a single duct. A small lump beneath the nipple may be felt by the examiner, but it is not always palpable (able to be felt with the fingers). A mammogram often does not show papillomas. Ultrasound may be helpful.

A breast biopsy is necessary to make a definitive diagnosis and rule out cancer.