Apparently primary, subepidermal epithelioid amelanotic malignant melanoma associated with a non-contiguous overlying hutchinson’s freckle. a variation on the desmoplastic melanoma concept?

In 1971, Conley, Lattes and Orr described an intradermal/ subcutaneous, amelanotic, spindle cell malignant tumour of the face of elderly individuals which was associated with an overlying, non-contiguous, Hutchinson’s melanotic freckle. They argued that the deep, sarcomatoid spindle cells arose from the overlying intraepidermal melanocytes and called the tumour ‘desmoplastic malignant melanoma’, an entity that has now gained general acceptance. We present a case of a subepidermal epithelioid amelanotic melanoma which arose beneath a noncontiguous, inconspicuous Hutchinson’s freckle with no nodular component, located over the angle of the left mandible. No other primary tumour was apparent. We propose that the pathogenesis of this tumour is similar to that of desmoplastic malignant melanoma, except that in this case, the melanoma cells did not undergo neurosarcomatous or mesenchymal metaplasia.