Chondroid syringoma: case report and review of the literature.

An 84-year-old man presented with an enlarging bluish, painless subcutaneous nodule on the glabella. The lesion had been excised 4 years prior and was diagnosed as chondroid syringoma, but had gradually regrown. The recurrent lesion was treated by surgical re-excision. Histopathological examination was again consistent with chondroid syringoma, and showed the following: 1) a chondroid matrix, 2) tubuloalveolar structures lined by a double epithelium, 3) ductal structures lined by a single epithelium, 4) nests of polygonal cells, and 5) the presence of keratinous cysts. Chondroid syringoma is a rare mixed tumor of the skin that was first described by Hirsch and Helwig. Characteristically, it is composed of a proliferation of epithelial cells set in a myxoid and chondroid matrix. Although chondroid syringomas are predominantly benign, malignant forms have been reported.