A case report of fibromatosis resulting in small bowel obstruction

Introduction: Fibromatosis, also known as desmoid tumors, is a benign tumor that is found in patients with a history of familial adenomatous polyposis (FAP) syndrome. Although, sporadic fibromatosis is more common than this classic association. Case Report: This case report describes a 75-year-old woman who was healthy and had no history of familial adenomatous polyposis (FAP). She presented with acute abdominal pain caused by a small bowel obstruction. Computed tomography (CT) imaging demonstrated a solid mass measuring 5 × 5 cm in the left mid-abdomen or the pelvis causing a proximal small bowel obstruction. The patient then underwent an exploratory laparotomy, during which a 45-cm segment of the jejunum, along with associated mesentery and lymph nodes, was resected due to a large mass and extensive adhesions. A primary small bowel anastomosis was performed subsequently. Macroscopic and microscopic pathology evaluations revealed a homogenous mass consistent with fibromatosis, indicating a benign tumor originating from the mesentery. This is an uncommon presentation of small bowel obstruction in an otherwise healthy female patient without a history of FAP. Conclusion: As this case shows, spontaneous fibromatosis can present aggressively and require emergency surgical intervention.