Congenital generalized fibromatosis.

Congenital fibromatosis is a rare form of fibroblastic proliferation, which may appear similar to fibrosarcoma; it is multicentric, involving soft tissues, viscera, and bones. The larger soft tissue tumors are very hemorrhagic and necrotic, and they may contain calcifications. Because these characteristics are also present in the more common hemangiomas of infancy, congenital fibromatosis can be diagnosed erroneously as hemangioma. We report a case of congenital generalized fibromatosis erroneously diagnosed initially as hemangioma. The multicentric tumor was aggressive, ultimately resulting in death.