Duct ectasia is a benign condition associated with loss of elastin within the walls of the duct, with an associated chronic inflammatory cell infiltrate.
This results in duct dilatation and shortening. Duct ectasia should be regarded as an aberration of normal breast involution affecting older women.
Patients may present with cheesy nipple discharge that may arise from one or multiple ducts. There may be an associated lump representing a dilated duct. Slit-like nipple retraction may be present and is a late feature.
Pressure on the areola will demonstrate discharge that is usually cheesy and there may be a palpable dilated duct with associated nipple retraction.
The majority of patients with duct ectasia have no diagnostic mammographic features. Occasionally the ducts are seen as tubular structures extending from the subareolar area, but this is a nonspecific sign. The purpose of mammography in such instances is to exclude underlying malignancy.
Duct ectasia can be seen as multiple tubular structures arising from the nipple. The significance of such findings is unclear, however, as it is frequently seen in otherwise normal individuals. Ultrasound therefore has no role to play in the diagnosis of patients with nipple discharge. It should only be performed in patients who are also found to have a palpable mass.
The large subareolar ducts are predominantly affected. The affected ducts are distended and palpable, and on cross section, they are filled with thick pultaceous material and may contain calcification in rare cases.
The dilated ducts contain amorphous material and foamy macrophages within them. The lining epithelium also contains infiltrating macrophages and may show reactive hyperplasia or attenuation. The periductal stroma shows varying degrees of inflammation and fibrosis. The fibrosis is usually concentric in distribution but may be irregularly distributed in plaques.
Stromal calcification may also be seen.
Provided assessment confirms the diagnosis of duct ectasia, the majority of patients can be reassured. Patients with troublesome discharge should be treated by total duct excision. The nipple should be everted as part of this procedure.
A.D. Purushotham, P. Britton and L. Bobrow
A prospective study of benign breast disease and the risk of breast cancer. JAMA 2002