Eccrine syringofibroadenoma (ESFA): a report of two cases.

Eccrine syringofibroadenoma (ESFA) is a rare neoplasm that usually presents as a solitary, often large, hyperkeratotic nodular lesion with predilection for the extremities. Histologically, there are thin anastomosing epithelial cords and strands forming a lattice and connected to the undersurface of the epidermis. Ducts are presented within the tumor. Between the strands, there is a rich fibrovascular stroma. Eccrine syringofibroadenoma is typically a rare benign neoplasm. Eccrine syringofibroadenoma (ESFA) is of acrosyringeal or eccrine dermal duct differentiation. Histologically, there are multiple anastomosing cords of benign epithelial cells surrounded by a loose fibrovascular stroma. The epithelial cords demonstrate ductal differentiation. Occasional luminal eccrine ducts are noted within the anastomosing cords. The authors describe two cases with different subtypes of ESFA, a solitary ESFA and a reactive ESFA with squamous cell carcinoma. Case report