Genodermatosis Affecting the Skin and Mucosa of the Head and Neck: Clinicopathologic, Genetic, and Molecular Aspect—PTEN-Hamartoma Tumor Syndrome/Cowden Syndrome

PTEN hamartoma tumor syndrome refers to a spectrum of disorders caused by mutations in the phosphatase and tensin homolog (PTEN) gene. Cowden syndrome, the principal PTEN-related disorder is characterized by multiple neoplasms and hamartomas, mucosal papillomatosis, and skin lesions, trichilemmomas. Trichilemmomas and mucocutaneous papillomatous papules are one of the first signs of the disease. Early recognition of these skin lesions may help on diagnosing an underlying malignancy and early cancer screening.