Musculoaponeurotic fibromatosis (extraabdominal desmoid tumor) in a child with idiopathic multicentric osteolysis.

The fibromatoses are a group of benign proliferations of fibrous tissue with clinical behavior ranging from that of truly malignant tumors to that of benign reactive fibrous proliferations. Some of the superficial fibromatoses are fairly common, but the deep ones, also known as desmoid tumors or musculoaponeurotic fibromatoses, are rare. Idiopathic multicentric osteolysis is a rare skeletal disorder of childhood that causes progressive destruction of bones and renal failure. We recently saw a young girl with both extraabdominal musculoaponeurotic fibromatosis and idiopathic multicentric osteolysis. The classification, diagnosis, and treatment of the deep fibromatoses are reviewed, and the possible association between the minor bone changes occasionally reported in musculoaponeurotic fibromatosis and idiopathic multicentric osteolysis is discussed.