Introduction to the Breast Quiz

See Clinical Presentations. Option E is correct. Galactorrhoea is milk production that is not related to pregnancy and breastfeeding. It is commonly caused by hyperprolactinaemia, which means a raised level of prolactin, the hormone made by the pituitary gland (a small gland at the base of the brain) that stimulates the breast to make milk. It is usually bilateral, comes from several ducts and is milky, although it can be yellow, green or brown. Hyperprolactinaemia is most often caused by medicines (most commonly antipsychotics and drugs that speed up gut movement) or associated with a pituitary adenoma (a benign tumour of the pituitary), called a prolactinoma when it makes prolactin. Less common causes include an underactive thyroid and kidney disease. By contrast, discharge from a single duct that is bloody or blood-stained, or that comes with a breast mass, needs evaluation for breast tumours. Pregnancy should also be excluded in any woman with milky discharge. Milky discharge alone does not establish raised prolactin or its cause, so blood tests and a medicines review are needed. A memory aid is that milky and on both sides is hormonal, while bloody and from one duct is a tumour until proved otherwise.

• Galactorrhoea: milk production that is not related to pregnancy and breastfeeding.
• Usual mechanism: hyperprolactinaemia, a raised level of prolactin from the pituitary gland.
• Causes: medicines such as antipsychotics, or a pituitary adenoma called a prolactinoma.
• Pattern: usually milky, from both breasts and several ducts, unlike bloody single-duct discharge which needs evaluation for tumours.