Endocrine Abstracts

We present a series of 18 cases with central mesenteric node resection in stage 4 small intestine NET (SI NET) managed under the guidance of New Zealand’s national NET multidisciplinary framework 2014-2025. This represents 80% of significant central node excision over this time (20% had surgery in other centres). These cases were a mix of (1) symptomatic, (2) approaching PRRT and (3) prophylactic. We followed the general strategy of resecting primaries and significant mesenteric node masses followed by appropriately timed PRRT as a standard management for stage 4 SI NET. Presence of ≥2 proximal uninvolved SMA branches was taken as a minimum requirement for resection. Staging of resected nodes in the classification of Ohrvall et al.(2000) was level 2: 9 cases; level 3: 8 cases; level 4: 1 case. 3 patients had concomitant duodenal resection. All patients left hospital independent on oral diet. 2 patients had right side cardiac valve replacements before abdominal surgery. 6 had PRRT at varying intervals. 2 had liver resection of limited and localised metastasis – we do not pursue major liver debulking unless for troublesome carcinoid syndrome or to facilitate PRRT to smaller lesions. One patient died 3 years after surgery with progressive disease, the remainder are alive 2-130 months post surgery. One patient had a subsequent abdominal operation for a SI perforation at 15 months but no other patients had later abdominal symptoms other than diarrhoea managed with typical medications. There is concern regarding PRRT in the presence of compromised SI – obstruction or vascular compromise – and it is not clear where the safety limits are. We show here that relatively aggressive mesenteric node resection is safe with good symptomatic outcome and can be followed by uncomplicated PRRT. A ‘mesentery-sparing’ surgical approach is important and does not appear to be widely known outside of NET centres. Internationally, curricula for training in General and Colorectal surgery typically have little coverage of SI NET surgery.