 The initial form of EV presents with only flat, wart-like lesions over the body, whereas the malignant form shows a higher rate of polymorphic skin lesions and development of multiple cutaneous tumors.Generally, cutaneous lesions are spread over the body, but some cases have only a few lesions which are limited to one extremity.The cause of the condition is an inactivating PH mutation in either the "EVER1" or "EVER2" genes, which are located adjacent to one another on chromosome 17.