Huge mesenteric desmoid-type fibromatosis with unusual presentation: A case report.

Introduction: Desmoid-type fibromatosis, also known as desmoid tumors, are rare fibroblastic neoplasms that account for less than 3% of all soft tissue tumors. Although they are benign neoplasms without metastatic potential, they are known to be locally aggressive and may invade adjacent structures leading to fatal complications. Case presentation: We describe the case of a 26-year-old woman who presenting with the clinical picture of acute peritonitis. Emergency surgery was performed and a large poorly-circumscribed heterogeneous tumor was found, occupying the jejunum mesentery and infiltrating the jejunal wall causing its perforation into the abdominal cavity. En bloc resection of the tumor and the involved jejunum was performed. Histology and immunohistochemistry confirmed it to be mesenteric desmoid-type fibromatosis. The postoperative course was uneventful and the patient had no evidence of recurrence 18 months after tumor resection. Conclusions: Mesenteric desmoid-type fibromatosis is a rare condition with insidious growth and locally aggressive behavior. Serious complications such as bowel perforation are rare but possible, as shown in our presentation. Complete surgical resection is the first-line treatment bur high recurrence rates remain problematic.