Ductal carcinoma in situ, low nuclear grade arising in a fibroadenoma

• Smooth muscle myosin heavy chain- cytoplasmic staining highlights myoepithelial cells
• P63: nuclear staining highlights intact myoepithelial cell layer

Nipple adenoma

Ductal carcinoma in-situ involving a sclerosing lesion (mimicking invasion)

• Smooth muscle myosin heavy chain- cytoplasmic staining highlights myoepithelial cells
• P63: nuclear staining highlights intact myoepithelial cell layer

Epithelial inclusion cyst involving an axillary lymph node (secondary to previous needle biopsy)

Diagnosis: Squamous metaplasia of lactiferous ducts (SMOLD)

 Myofibroblastoma

• CD34- Diffuse cytoplasmic staining of the spindle cells

CD34- Diffuse cytoplasmic staining of the spindle cells

Fibromatosis

Metaplastic carcinoma (spindle cell carcinoma)