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
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
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
May be a secondary change associated with nearby intraductal papilloma
