Syringoma, malignant, chrondroides C79.2

Very rare form of malignant adnexal tumor (about 40 cases have been described in the literature so far) with apocrine differentiation. Metastasis to the regional lymph nodes, but distant metastases may also occur. Mostly histological incidental finding in clinically not clearly classifiable tumor.

As in the benign course (see below mixed tumor of the skin), myxoid degeneration of the matrix and adenoid tumor nests and strands of different size are typical. The malignant chondroid syringoma shows only few mitotic figures with a distinct myxoid degeneration; also a relatively low cell and nuclear polymorphism.

Immunohistology: Differently expressed reactivity for GFAP (glial fibrillary acidic proteins), cytokeratin and S100 protein.

1. Gartmann H et al (1992) Malignant mixed tumour of the skin (malignant chondroid syringoma). Act Dermatol 18: 119-121
2. Deer P, Helwig EB (1961) Chondroid syringoma. Mixed tumor of skin, salivary gland type. Arch Dermatol 84: 835-847
3. Raitz R et al (2003) A study of the extracellular matrix in salivary gland tumors. J Oral Catholic Med 32: 290-296
4. Takahashi H et al (2004) Malignant chondroid syringoma with bone invasion: A case report and review of the literature. Amm J Dermatopathol 26: 403-406