A 40-year-old heavy smoker has recurrent subareolar breast abscesses with fistula formation to the periareolar skin. Histology shows squamous metaplasia of the lactiferous ducts with keratin plugging and marked periductal inflammation. This entity is best classified as:

• A Mammary duct ectasia
• B Periductal mastitis ✓
• C Acute mastitis due to Staphylococcus aureus
• D Idiopathic granulomatous mastitis

Explanation

Periductal mastitis (recurrent subareolar abscess, Zuska disease) occurs in young smokers and is driven by squamous metaplasia of lactiferous ducts with keratin obstruction, leading to recurrent abscess and mammary fistula. Mammary duct ectasia affects older multiparous women, presents with a palpable mass and thick white secretions, and shows dilated ducts with inspissated debris and periductal fibrosis without squamous metaplasia. Acute mastitis occurs during lactation, and idiopathic granulomatous mastitis shows non-caseating lobular granulomas.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.