Iris mammillations in a pair of twins with Cowden syndrome

CS: Cowden syndrome PTEN: phosphatase and tensin homolog INTRODUCTION Iris mammillation is an uncommon congenital anomaly of the eye that is rarely reported in the literature; initial reports describe iris mammillations using different terminology, such as bilateral iris melanosis, dotted Swiss iris, and bilateral diffuse iris nodular nevi. Microscopic examination finds focal nesting of spindle-shaped melanocytes, hence, the name diffuse iris nodular nevi. The etiology of iris mammillations is unknown and when coexisting with ocular melanocytosis, it has been associated with choroidal melanoma. Cowden syndrome (CS) is a hereditary cancer syndrome characterized by the development of multiple hamartomas and an increased risk of malignant neoplasms in multiple organs. Here we report on identical twins with CS in association with iris mammillations. To our knowledge, this is the first time this association has been reported.