The emergence of epidermal epitheliomas in the scars of patients with polydysplastic epidermolysis bullosa is the result of a carcinogenic process similar to that observed in the scars of thermal burns and other chronic cicatrices. In three of the four cases, the patients developed multiple, well-differentiated squamous-cell cancers; in one patient basal-cell epitheliomas were also present. Confirmation of cancer histologically was difficult because of limitations in distinguishing pseudoepitheliomatous hyperplasia from squamous-cell cancer. There was no doubt of carcinomatous conversion biologically, however, as metastases occurred in the patients. Therapy was inadequate; and despite its limitations, surgery seems to be the treatment of choice.
Wechsler HL, Krugh FJ, Domonkos AN, Scheen SR, Davidson CL. Polydysplastic Epidermolysis Bullosa andDevelopment of Epidermal Neoplasms. Arch Dermatol. 1970;102(4):374-380. doi:10.1001/archderm.1970.04000100022006