Cowden’s Syndrome

A rare autosomal dominant hamartoma/neoplasia syndrome [MIM 158350] characterised by multiple hamartomas—which arise from all three germ cell layers, most prominently from the ectoderm and endoderm, in particular hamartomas of skin and the GI tract, from the stomach to the colon—and an increased risk of developing cancer, including the breast, thyroid, and uterus. Women with Cowden’s syndrome have up to a 50% lifetime risk of developing breast cancer and up to 75% have benign breast disease—fibroadenomas, fibrocystic changes