Zollinger ellison syndrome due to primary nodal gastrinoma located outside the limits of the conventional gastrinoma triangle: report of a case

Abstract

Primary nodal gastrinoma is a rare entity and the diagnosis is often contemplative when no other non - nodal primary site can be identified despite thorough investigations and operative exploration. Here we report one such case wherein a primary nodal gastrinoma was diagnosed as an entity of exclusion. Additionally, the location of the disease outside the confines of the conventional gastrinoma triangle further contributes to the rarity of the presentation. A young male patient had presented to us with history of multiple operations in the past for recurrent upper abdominal pain presumably consequential to peptic ulcer disease viz a trucal vagotomy and gastrojejunostomy, duodenal ulcer perforation surgery and a cholecystectomy. CT scan and endoscopic USG showed a preaortic calcified node located outside the limits of the gastrinoma triangle. A raised serum gastrin level and an endoscopic guided FNAC confirmed the diagnosis of a gastrinoma. A 68 Ga-DOTANOC PET CT revealed an exclusive nodal uptake with no discenable primary lesion. Normalization of gastrin levels after removal of the involved pre-aortic node further pointed to the diagnosis of primary nodal gastrinoma. A high index of clinical suspicion is warranted especially in a history of multiple surgeries for recurrent upper abdominal pain and location of the lesion outside the confines of the ‘Gastrinoma Triangle’ should not be deterrent for the diagnosis.