SOX10

Formalin-fixed, paraffin embedded tissue block or cell block, or 1 unstained charged slide for each test requested plus 3-4 additional unstained slides cut at 4 microns. Adequate space on each slide for control tissue is required.

A nuclear transcription factor involved in neural crest development and essential for melanocytic and schwannian differentiation. It is a sensitive and relatively specific marker for melanoma when used in a proper context, and maybe particularly helpful in the diagnosis of desmoplastic melanoma (however, be aware that some fibroblasts in scar have been reported to show SOX10 reactivity). SOX10 is also positive in nevi, clear cell sarcoma, and various peripheral nerve sheath tumors, including schwannoma, neurofibroma, and a subset of MPNST. It also labels sustentacular cells of paraganglioma/pheochromocytoma.