Primary chondroid melanoma of the nasal skin: a rare melanoma variant at a previously undocumented site.

Heterologous differentiation is exceedingly rare in melanoma. Only four cases of melanoma demonstrating exclusive cartilaginous differentiation have been documented, all having occurred on the lower extremity. We report a chondroid melanoma involving the nasal skin and presenting clinically as a basal cell carcinoma. Both Melan-A and microphthalmia transcription factor protein immunoperoxidase stains were positive in our case, demonstrating the potential utility of these two stains in chondroid melanoma. We also provide a succinct review of the literature on this rare melanoma variant.