Syringometaplasia: mucinous and squamous variants.

Area of Science:

• Dermatopathology
• Oncology

Background:

• Eccrine sweat ducts are typically lined by cuboidal epithelial cells.
• Metaplasia, specifically syringometaplasia, is a rare alteration of these cells.

Observation:

• Two distinct cases of syringometaplasia were analyzed: a mucinous variant and a squamous variant.
• The mucinous variant presented as a plantar lesion resembling a wart, featuring goblet cells and mucin.
• The squamous variant occurred on the ear, showing atypical squamous cells in the dermis.

Findings:

• Mucinous syringometaplasia involves eccrine ducts with mucin-filled goblet cells, distinguishable by Alcian blue and mucicarmine stains.
• Squamous syringometaplasia is characterized by atypical squamous cell islands in the dermis, with some containing lumina and cuticles, connected to ductal structures.

Implications:

• Accurate identification of mucinous syringometaplasia is vital to prevent confusion with primary or metastatic skin adenocarcinoma.
• Distinguishing squamous syringometaplasia from invasive squamous cell carcinoma is essential for appropriate patient management.
• Squamous syringometaplasia may share similarities with necrotizing sialometaplasia observed in salivary glands.