Some speculations on the histogenesis of desmoplastic melanoma

Opportunity to have observed a case of Desmoplastic Melanoma showing a somewhat particular clinical presentation led to the review of the literature on the subject and offered an opportunity for some speculation about the histogenesis of this lesion. From the examination of our case and from the review of the literature, it emerged that the starting factor is a dedifferentiated tumorigenic cell clone originated in a Lentigo Maligna. This clone would be capable of triggering in the surrounding dermis as a proliferative phenomenon with the characters of a fasciitis-like PMP (Pseudosarcomatous Myofibroblastic Proliferation) that would constitute the desmoplastic component of the tumor. This phenomenon of the PMPs-related tumor has been widely demonstrated to date, only in association with squamous superficial carcinom of mucous membranes. In our case, the “fulminant” relapse finds an explanation in the onset of a Spindle cell Postoperative Nodule, lesion, even this one, belonging to PMPs group, characterized by rapid onset after a surgical trauma.