An apparent primitive mass of the mesentery

Abstract

Introduction: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.Patient concerns: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.Diagnosis: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.Interventions: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.Outcomes: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.Conclusion: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.

Two synchronous primary mesenteric neuroendocrine tumors in a patient: a case report

“…Besides their common location in ileac or jejunal mesentery, primary mesenteric NETs have been reported to be located in the gastrohepatic ligament ( 3 ), and even in the mesocolon ( 4 ). They can be sporadic, or associated with a syndrome, such as multiple endocrine neoplasia type 1, neurofibromatosis type 1, and von Hippel-Lindau ( 5 ).…”

“…In addition, it is a useful tool for the evaluation of possible recurrence ( 9 ), and in combination with FDG PET/CT was found to be helpful for the therapeutic approach of GEP-NETs, especially of the poorly- differentiated ones ( 9 ). However, there is a possibility that small intestinal NETs with a diameter less than 5 mm might not be apparent even in 68-Gallium PET ( 5 ). In our case, 68-Ga DOTATATE PET was used before the second operation and after the histologic confirmation of the first mesenteric NET, in particular six months after the first operation, excluding other possible primary lesions.…”

“…For primary mesenteric NETs, there are not enough data in order to establish clear recommendations, although many authors have proceeded with lymph node sampling. Subrenal retrocaval and interaortocaval lymph node resection has also been reported in the literature, for clinically positive lymph nodes ( 5 ).…”