Mammary Duct Ectasia
Definition
- A subareolar periductal chronic inflammatory process that in early stages is characterized by dilated ducts but eventually produces ductal obliteration
Alternate/Historical Names
- Cholesterol granuloma
- Comedomastitis
- Mastitis obliterans
- Plasma cell mastitis
- Periductal mastitis
Diagnostic Criteria
- Early lesions
- Centered on subareolar ducts
- May spread
- Dilated ducts may contain:
- Foamy histiocytes
- Polyps containing histiocytes have been reported as "lipophagic polyps"
- Proteinaceous secretion
- Cholesterol crystals
- Calcification
- Foamy histiocytes
- Periductal inflammation
- Circumferential
- Lymphocytes, plasma cells and histiocytes
- May contain foreign body giant cells (granulomatous periductal mastitis)
- Plasma cells when prominent have lead to the designation of the lesion as “plasma cell mastitis”
- May form abscess or fistula
- Epithelium usually atrophic
- May show squamous metaplasia
- May be replaced by granulation tissue
- Periductal fibrosis
- Centered on subareolar ducts
- Late lesions
- Sclerosis may lead to duct obliteration
- Termed “mastitis obliterans”
- Elastic tissue stain may be used to demonstrate presence of obliterated duct
- Recanalization around the periphery of ducts by small tubules
- Termed “garland pattern”
- Epithelium may be totally destroyed
- Sclerosis may lead to duct obliteration
- May be a secondary change associated with nearby intraductal papilloma
Richard L Kempson MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting:: May 27, 2006
