Mammary duct ectasia is a benign condition where there is dilation of the large ducts in the breasts. Ectasia means dilation. There is inflammation in the ducts, leading to intermittent discharge from the nipple. The discharge may be white, grey or green.
Mammary duct ectasia occurs most frequently in perimenopausal women. Smoking is a significant risk factor.
Presentation
Mammary duct ectasia may present with:
- Nipple discharge
- Tenderness or pain
- Nipple retraction or inversion
- A breast lump (pressure on the lump may produce nipple discharge)
It may be picked up incidentally on a mammogram, leading to further assessment and investigations.
Diagnosis
The initial priority is to exclude breast cancer, as they can present in similar ways. This involves triple assessment with:
- Clinical assessment (history and examination)
- Imaging (ultrasound, mammography and MRI)
- Histology (fine needle aspiration or core biopsy)
Microcalcifications are a key finding to remember on a mammogram, although they are not specific to mammary duct ectasia.
Other investigations that may be performed:
- Ductography – contrast is injected into an abnormal duct, and mammograms are performed to visualise the duct
- Nipple discharge cytology – examining the cells in a sample of the nipple discharge
- Ductoscopy – inserting a tiny endoscope (camera) into the duct
Management
Mammary duct ectasia may resolve without any treatment. It is not associated with an increased risk of cancer.
Management depends on the individual patient:
- Reassurance after excluding cancer may be all that is required
- Symptomatic management of mastalgia (supportive bra and warm compresses)
- Antibiotics if infection is suspected or present
- Surgical excision of the affected duct (microdochectomy) may be required in problematic cases
Last updated June 2021