Nipple discharge is common and is used to describe the release of fluid from the nipple. It can be associated with normal breasts as a physiological change which can occur in approximately 50–70% of women.
In some cases, nipple discharge may be related to an underlying benign (non- cancerous) or malignant breast condition (uncommon).
There are certain features of nipple discharge which need to be determined to further identify its cause and subsequent treatment plan. Nipple discharge can be:
Spontaneous (nipple discharge occurring without squeezing/pressure on the nipple)
Upon expression (nipple discharge occurring when the nipple is squeezed or pressured), this is generally not related to underlying breast disease
Unilateral (from one breast) or bilateral (occurring in both breasts)
Single duct (discharge from a single duct/spot on the nipple) or multi duct (discharge occurring from several nipple ducts or spots)
Yellow/green or milky due to benign, normal physiological discharge
Blood stained/red/brown or clear as water- this type of nipple discharge may be related to underlying breast conditions such as benign or malignant disease
Physiological (normal) Nipple discharge
This discharge is usually yellow, milky, or green in appearance, and it does not generally happen spontaneously. It can often be seen to be coming from more than one duct and sometimes from both breasts. Physiological nipple discharge is no cause for concern.
Milky nipple discharge (either spontaneous or on expression) is also generally normal (physiological).
Pathological (abnormal) Nipple Discharge
This type of nipple discharge is abnormal. It is generally spontaneous and unrelated to pregnancy or breastfeeding. In most cases, it has a non-cancerous (benign) cause. Spontaneous nipple discharge that is caused by disease (pathology) in the breast is more likely to be from one breast only (unilateral), confined to a single duct, and clear or blood-stained in appearance.
Nipple discharge that is associated with a breast lump or changes in breast shape should undergo clinical examination, breast imaging and possible biopsy.
Rarely some nipple discharge can be a sign of a malignant condition (see nipple discharge malignant condition)
This is a benign (non-cancerous) condition in which the milk ducts under the nipple widen with some inflammation in the walls of the ducts. It usually occurs in women after menopause. This can cause pooling of secretions leads to nipple discharge.
This discharge is usually from both breasts, yellow/greenish in colour and tends to involve more than one single duct.
Surgical treatment is needed if there is extensive discharge causing impaired quality of life.