BREAST CYTOPATHOLOGY

Cytomorphologic Characteristics
• Smear cellularity is highly dependent on the clinical stage
of the lesion—high cellularity in the acute/active stage and
sparse cellularity in the subacute/chronic stage due to presence
of varying degrees of fibrosis.
• Smears contain abundant mixed inflammatory cells (neutrophils,
lymphocytes, and plasma cells), apocrine cells,
and abundant macrophages often with evidence of cytophagocytosis
and multinucleated giant cells.
• Isolated cells, apocrine cells, and clusters of epithelial cells
with varying degrees of reactive atypia are also present
(often with an appearance reminiscent of epithelial cells in
repair).
Pitfalls and Differential Diagnosis
• Ductal carcinoma
• Fat necrosis with organized hematoma
Chronic Subareolar Abscess
Clinical Features
• This is considered a specific clinicopathologic entity characterized
by low-grade/mild infection of the lactiferous
duct or sinus leading to subsequent abscess formation and/
or chronic recurrent infection and rarely fistula formation
at the base of the nipple.
• Suggestion has been made that squamous metaplasia of
columnar epithelial cells of the lactiferous ducts is the cause
of this lesion.
Cytomorphologic Characteristics
Chronic Subareolar Abscess 17
• High cellularity
• Mixed inflammatory infiltrate, abundance of neutrophils
and lymphocytes with few plasma cells, and multinucleated
giant cells