Application Of Endoscopic Ultrasonography In The Diagnosis,Assessment And Treatment Of Gastrointestinal Neuroendocrine Tumors

Background and objective:Neuroendocrine tumors (NETs), as rare, malignant tumors, occur mostly in gastrointestinal (GI) tract. These tumors secrete peptide hormones and biogenic amines that are regulated by the autonomic nervous system and influence the function of the GI system. Different kinds of endoscopic technologies often be applied to assess them. Our study aims to evaluate the efficacy of endoscopic ultrasonography (EUS) in the diagnosis and treatment selection for GI NETs and to analyze clinicopathological characteristics of these tumors.Methods:Eighty-four patients with suspected NETs based on EUS from the Endoscopy Center of the First affiliated Hospital, Zhejiang University, China and Yinzhou Hospital, Ningbo, China between January 1,2009 and December 31,2014 were enrolled. The clinicopathological data were recorded and analyzed.Results:NETs were confirmed in 83.3%(70/84) of these patients by pathological examination. Among the upper GI tract NETs patients,61.1% of them suffered from abdominal pain, and bloating occurred in 41.6% of the patients.75% of the tumors were located in the stomach. The mean diameter was 1.06±0.82 cm. Most tumors were stage G1 and infiltrated the mucosa or submucosa. Most patients were positive for synaptophysin (Syn), followed by chromogranin A (CgA) and CD56. The majority of patients (86.1%) chose endoscopic submucosal dissection (ESD). Among colorectal NETs patients,26.5% exhibited soft stool or increased defecation frequency.91.4% tumors were located in the rectum,infiltrated to submucosa layer, and the majority of the tumors were less than 10mm. Pre-operation CT scan finding lesions seemed no differentiation with diverse symptoms, tumor origination, locations, sizes and surface conditions (P>0.05). The G1 stage tumors was 93.8%. Syn and CgA were the most sensitive markers. The majority of patients chose ESD (52.9%), followed by TEM (29.5%). The treatment selection was related to tumor sizes (P=0.029). Large tumor bled more than smaller ones in operations (P=0.017). Tumor locations and origination had no relation with hemorrhagic volume (P>0.05).Conclusion:EUS exhibited good accuracy in the diagnosis and evaluation of GI NETs and made a contribution to treatment planning. Using EUS in combination with other examination methods may provide better efficiency.