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cutaneous mixed tumor

Wednesday 21 September 2011

Cutaneous mixed tumors, also known as chondroid syringomas, are benign cutaneous adnexal tumors that exhibit remarkable histopathological similarities to pleomorphic adenoma of the salivary gland.

All cutaneous mixed tumors are immunoreactive to PLAG1, which is predominantly expressed in cells with myoepithelial or chondroid differentiation accounting for >80% of cells, whereas PLAG1 expression in glandular or squamous tumor cells is restricted to < 20% of cells.

The carcinoma component in the mixed tumor is also positive for PLAG1.

On the other hand, all cutaneous adnexal tumors other than the mixed tumor are negative for PLAG1.

In RT-PCR analysis, no fusion gene transcripts involving PLAG1 or HMGA2 are identified in any of the cases.

References

- PLAG1 expression in cutaneous mixed tumors: an immunohistochemical and molecular genetic study. Matsuyama A, Hisaoka M, Hashimoto H. Virchows Arch. 2011 Sep 17. PMID: 21927843