BACKGROUND: Desmoid-type fibromatosis (DF) is a rare entity that predominantly involves the extremities, the trunk, and the abdominal cavity. It is a non-metastasizing, sporadic mesenchymal tumor with high tendency to recurrence and often is categorized as low-grade sarcoma.

CASE REPORT: We present here an extremely rare case of a mesenteric desmoid tumor (DT). A 40-year-old man presented to our clinic with a mass in the right-lower quadrant of the abdomen, which he incidentally palpated. A computerized tomography (CT) scan of the abdomen showed a mass between the loops of small intestine. The patient was treated successfully with wide excision of involved mesentery and adjacent small intestine. Histopathology of the mass revealed DT of the mesentery. No adjuvant treatment was applied and the patient was free of disease after a 6-month follow-up.

CONCLUSIONS: Intra-abdominal DF is a rare pathology which should be differentiated while exploring abdominal tumors. Surgery, when dealing with operable masses, is the appropriate treatment.

Keywords: Fibromatosis, Aggressive - surgery, Mesentery, Peritoneal Neoplasms - surgery