Insulinoma after sleeve gastrectomy: A case report

Abstract

BACKGROUND Laparoscopic sleeve gastrectomy (LSG) has been proposed as an effective and durable treatment for severe obesity and glucose metabolism disorders, and its prevalence has increased from 5% to 37% since 2008. One common complication after bariatric surgery is a postprandial hyperinsulinemic hypoglycemic state. While rare, insulinomas can cause this state, where symptoms are more common in the fasting state; thus, evaluation of insulin secretion is needed. Until now, there have been no reports of insulinoma after LSG. CASE SUMMARY We describe the case of a 43-year-old woman who was referred to the obesity clinic 2 years after LSG was performed. She had symptoms of hypoglycemia predominantly in the fasting state and documented hypoglycemia of less than 30 mg/dL, which are compatible with Whipple’s triad. Initially, dumping syndrome was suspected, but after a second low fasting plasma glucose was documented, a 72-h fasting test was performed that tested positive. Computed tomography and endoscopic ultrasound were performed, identifying the presence of a homogeneous hypoechoic semioval tumoral lesion in the pancreas. The diagnosis was compatible with insulinoma. After laparoscopic enucleation of the insulinoma, the symptoms and hypoglycemia disappeared. The histopathological report described a well-differentiated grade 2 neuroendocrine tumor with positive chromogranin and synaptophysin and Ki67 immunopositivity in 4% of the neoplastic cells. CONCLUSION Insulinoma after LSG is a rare condition, and clinicians must be aware of it, especially if the patient has hypoglycemic symptoms during the fasting state.

Recurrent Hypoglycemia After Total Gastrectomy: A Case Report and Literature Analysis

“…Imaging plays a crucial role in localizing and diagnosing insulinomas. When insulinoma is strongly suspected, pancreatic MRI is considered the imaging test of choice for this condition and can provide confirmation of the diagnosis [9]. Insulinomas generally develop slowly.…”

Insulinoma After Bariatric Surgery: Tricks for Diagnosis and Therapeutic Approach

“…Insulin resistance caused by the obesity as well as lack of awareness of symptoms of hypoglycemia by the patients, may contribute to the delay in the identification of the insulinoma. Patients often fail to recognize autonomic warning symptoms and the hypoglycemia is only detected through the presence of neuroglycopenic symptoms delaying the diagnosis of the insulinoma for up to 5 years [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37].…”