An apparent primitive mass of the mesentery: A case report

Neuroendocrine tumours (NETs) are rare tumors. 55% of NETs originate in the gastrointestinal tract and the liver is the most common site of distant metastases. Serum chromogranin A is the most common biomarker for assessing the extent of disease and monitoring treatment; carcinoid syndrome occurs in 19% of NETs and is characterized by chronic diarrhea or flushing. Primary mesenteric NETs are rare and have been described only in case reports in literature; our case is an apparent primary mesenteric NETs with a surgical program to remove the mesenteric mass and subrenal interaortocaval and retrocaval lymphadenectomies.

A 73-year old man came to us because he had been experiencing abdominal pain for a year and he had recently developed diabetes mellitus. He was an active smoker with arterial hypertension.

After a computed tomography scan and 68 Gallium-positron emission tomography, a diagnosis of what appeared to be a primary mesenteric NET with retrocaval and interaortocaval lymph nodes was made. Laparoscopic biopsy showed NET G2 positive for serotonin, chromogranin A, synaptophysin.

The intraoperative finding of a primitive ileum-NET changed the surgical program. We removed the mesenteric mass with the lymph nodes of the superior mesenteric vessel and the middle distal ileum along with the cecum.

The postoperative course was normal, and the patient was discharged on the seventh postoperative day without signs of short bowel syndrome. Follow-up at 6 months revealed no evidence of short bowel syndrome or disease progression.

68 Gallium-positron emission tomography does not show NETs smaller than 0.5 mm. Accurate palpation of the intestine is essential during surgery for NETs for two reasons: to find the primitive, and because of the risk of multiple intestinal primitives.