Mesenteric infiltrative desmoid tumor bordering the pancreas and mimicking liposarcoma

Summary

A 53-year-old man was referred to our institution with an abdominal mass that was found incidentally on ultrasonography for prostate cancer screening. Multidetector computed tomography (MDCT) showed a cystic and solid mass with fat components in the ileal mesentery, measuring 25 cm in size. The mass was insinuating into the ileal vessels, invading the mesenteric side of jejunal loops, closely abutting the third portion of the duo-denum and uncinate procsess of the pancreas. The differential diagnosis included infiltrating liposarcoma, gastrointestinal stromal tumor (GIST), desmoid tumor (DT) and malignant peripheral nerve sheath tumor (MPNST) with entrapment of the mesneteric fat. Based on the imaging findings, surgical treatment of the en block resection of the mass was planned. A mesenteric mass excision with partial pancreatectomy, duodenectomy and small bowel segmental resection was performed. The mass encompassed duodenum, first jejunum loops and their mesentery. The resected specimen consisted of a large firm and white mesenteric mass, 24 × 11 cm, attached to the duodenum, small intestine and the uncinate process of the pancreas.