Melanoma with rhabdomyosarcomatous features: a potential diagnostic pitfall.

Malignant melanoma is well-known for phenotypic plasticity, and rare cases of divergent differentiation have been described. This case report is of a tumour diagnosed as 'rhabdomyosarcoma' on the face of a man in his 80s. However, given the recent excision of an ulcerated melanoma (Breslow thickness 5.8 mm) from the same site, the more likely diagnosis would be recurrent melanoma with rhabdomyosarcomatous differentiation. This highlights a rare form of divergent differentiation and a potential diagnostic pitfall.