Occult insulinoma after oesophagectomy for oesophageal cancer-diagnostic challenges

Abstract

Hypoglycaemia in the post-operative period is mainly iatrogenic (related to anti-hyperglycaemic drugs), but can be explained by an endogenous hyperinsulinemic state. In the context of previous gastrointestinal surgery, a form of dumping syndrome can mask hypoglycaemia from an underlying cause, such as an insulinoma. The authors present a clinical case of a male patient who underwent oesophageal surgery for an oesophago-gastric junction adenocarcinoma and developed hypoglycaemic symptoms in the post-operative period, caused by an undiagnosed insulinoma. This case report portraits the diagnostic investigation of a hypoglycaemia state in the post-operative period, narrowing to the workup of an endogenous hyperinsulinemic hypoglycaemia and provides a summary of insulinoma’s treatment. An insulinoma should always be considered in a patient with endogenous hyperinsulinemic hypoglycaemia, even with a history of oesophago-gastric surgery.