Eccrine syringofibroadenoma (Mascaro) - An immunohistochemical study

Eccrine syringofibroadenoma is an uncommon benign eccrine tumor, which was first described by Mascaro in 1963. It usually develops on the extremities of elderly persons. We report on a 74-year-old man who presented with a 2-y ear history of a slowly growing lesion on his face. A detailed histologic a nd immunohistochemical study was performed on the biopsy material. The tumo r consisted of epidermal-derived anastomosing thin epithelial cords embedde d in a fibrovascular stroma. The epithelial cords contained ductal and cyst ic structures lined by luminal cells, which were decorated by antibodies ag ainst carcinoembryonic antigen, keratin K19, K8, and K18. Antibody to kerat in K6 decorated the luminal walls of the acrosyringia. Antibodies to filagg rin decorated the superficial luminal structures. These results suggest dua l acrosyringial and dermal duct differentiation in syringofibroadenoma.