[Syndroms associated with benign skin tumors]

Benign skin tumors represent a wide category of diseases. The diagnosis is usually provided by the clinical aspect and the patient history. The pathological examination is not always considered necessary and in most cases the treatment is removal of the lesion by cryotherapy, electrosurgery or laser ablation. Deep phenotyping, including genetic and epigenetic findings, provided the basis of a new understanding of the pathogenetic mechanisms. Some benign skin tumors can be part of syndromes and the dermatologist should be aware of the extracutaneous associations defining these rare disorders: epidermal nevus can be associated with vascular malformations; nevus sebaceous can be associated with cerebral, ocular, and skeletal defects; nevus Becker is associated with cerebral, ocular, and skeletal defects; pilomatricomas appear earlier than colorectal cancer in Gardner's syndrome; tuberous sclerosis complex can associate not only central nervous system lesions but also pulmonary, cardiac or renal manifestations.