Bilateral fibromatosis of the breast in Gardner's syndrome

A 21-year-old woman with Gardner's syndrome (colonic polyposis with soft tissue and bone tumors) and bilateral fibromatosis of the breast is presented. Six other members of her family had polyposis of the colon, and 4 of them had 2 or more manifestations of Gardner's syndrome. One patient, a 21-year-old man, had an osteochondroma of the femur. Fibromatosis of the breast and osteochondroma are unusual findings in patients with familial polyposis. The colons were compared to those from 8 patients with polyposis without soft tissue or bone tumors, and no differences were observed. Gardner's syndrome and familial polyposis may be produced by a single pleiotropic gene with varying expressivity.