1. hamartoma syndrome, multiple A hereditary disease characterized by multiple ectodermal, mesodermal, and endodermal nevoid and neoplastic anomalies. Facial trichilemmomas and papillomatous papules of the oralmucosa are the most characteristic lesions. Individuals with this syndromehave a highrisk of BREAST CANCER; THYROID CANCER; and ENDOMETRIAL CANCER. This syndrome is associated with mutations in the gene for PTEN PHOSPHATASE.