ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2017) 52 P29 | DOI: 10.1530/endoabs.52.P29

Endoscopic submucosal dissection (ESD) of gastric and rectal neuroendocrine tumours (NETs)

Alberto Murino1, James Bailey2, Andrea Telese1, Faidon-Marios Laskaratos3, Nikolaos Koukias1, Erasmia Vlachou1, Tu Vinh Luong4, Dalvinder Mandair3, Martyn Caplin3, Christos Toumpanakis3 & Edward Despott3

1Royal Free Unit for Endoscopy, London, UK; 2Medical School, University College London, London, UK; 3Neuroendocrine Tumour Unit, Royal Free Hospital, London, UK; 4Academic Department of Cellular Pathology, London, UK.

Background: Gastrointestinal (GI) neuroendocrine tumours (NETs) are potentially malignant lesions originating from the enterochromaffin cells of the GI tract. These neoplasms often produce characteristic hormonal syndromes and can cause debilitating symptoms. Endoscopic submucosal dissection (ESD) is a well-established, complex, endoscopic technique, which allows for full resection of the mucosal and submucosal lesions without the need for open surgery.

Methods: We retrospectively reviewed all cases of GI NETs resected by ESD at the Royal Free Hospital between October 2014 and June 2017. Demographic, endoscopic, histopathological and follow-up data were collected and analysed.

Results: Six ESD’s were performed on five patients (all women mean age 57.8±12.1 years). Of the six NETs, there were five located in the stomach (83%) and one in the rectum (17%). All of the gastric NETs were identified as type 1. The main presenting symptoms in patients with gastric NETs were epigastric discomfort, dyspepsia, weight loss, tiredness and gastro-oesophageal reflux. In the case of the rectal NET, the patient presented with similar non-specific abdominal symptoms, but also bleeding per rectum. One patient was identified after a routine workup prior to bariatric surgery. 68Ga-DOTATATE PET/CT imaging revealed no distant sites of disease in any of the patients. Median lesion diameter was 13 mm (range 4.7–16 mm). Histopathological analysis showed three (50%) well-differentiated grade G1 NETs and three (50%) well-differentiated grade G2 NETs. Using the European Neuroendocrine Tumour Society classification staging system there were four pT1 (67%) and two pT2 (33%) lesions. After ESD, R0 resection was obtained in five lesions (83%) with R1 resection being encountered in one case (17%). No significant adverse events (i.e. perforation, bleeding, sepsis or need for surgery) were observed. Follow-up beyond three months (range: 28-5 months, mean follow-up 21.7 months) showed that all four patients with R0 resections had no evidence of recurrence.

Conclusion: ESD has been demonstrated to be a reliable, minimally invasive therapeutic tool for the resection of gastric and rectal NETs