Genetic testing by cancer site: skin.

Many hereditary cancer predisposition syndromes are associated with cutaneous findings, both benign and malignant. Dermatological examination and histopathology, when combined with a thorough personal and family medical history, play an important role in the diagnosis of cancer predisposition syndromes. Skin findings are an important diagnostic tool for a variety of cancer syndromes, including Cowden syndrome, Birt-Hogg-Dubé, hereditary leiomyomatosis renal cell carcinoma, and others. This article focuses on the phenotype, medical management, and genetic testing for 4 hereditary cancer syndromes that include cutaneous findings: hereditary melanoma, basal cell nevus syndrome, neurofibromatosis type 1, and neurofibromatosis type 2.