Eccrine syringofibroadenoma (Mascaro): an immunohistochemical study

Area of Science:

• Dermatopathology
• Oncology
• Histology

Background:

• Eccrine syringofibroadenoma (ESF) is an uncommon benign eccrine tumor.
• First described by Mascaro in 1963, it typically affects elderly individuals on the extremities.

Observation:

• A case report of a 74-year-old man with a 2-year history of a slowly growing facial lesion.
• Histologic examination revealed epidermal-derived epithelial cords in a fibrovascular stroma.

Findings:

• Immunohistochemistry showed epithelial cords with ductal and cystic structures.
• Luminal cells expressed carcinoembryonic antigen, keratin K19, K8, and K18.
• Keratin K6 decorated acrosyringial luminal walls, and filaggrin decorated superficial luminal structures, suggesting dual differentiation.

Implications:

• The findings suggest a dual differentiation pathway for eccrine syringofibroadenoma.
• This enhances understanding of eccrine tumor histogenesis and classification.