Extraabdominal fibromatosis in retroperitoneal space.

Background: Fibromatosis or desmoid tumor covers a broad spectrum of benign fibrous tissue proliferations. It is characterized by infiltrative growth and a tendency towards recurrence; however, unlike sarcoma, it never metastasizes.

Case Presentation: We report on a case of extraabdominal fibromatosis originating from the retroperitoneal space in a 43-year-old woman.