title: Insulinoma Due to Multiple Pancreatic Microadenoma Localized by Multimodal Imaging.
abstract: Insulinomas are usually due to a solitary tumor, but they can be challenging to localize.
  
  
  
  A 66-year-old woman presented with a 1-year history of episodic neuroglycopenic hypoglycemia and was suspected of having an insulinoma. On a supervised fast, she was found to be hypoglycemic at 39 mg/dL, with an insulin of 40 μU/mL 26 hours into the fast and a proinsulin of 35 pmol/L. Contrast-enhanced computed tomography and magnetic resonance imaging did not localize a pancreatic lesion. Intra-arterial calcium stimulation testing showed a step-up of venous insulin levels at injection of the superior mesenteric artery and proximal and mid-splenic artery, and a68Ga-DOTATATE positron emission tomography/computed tomography showed focal uptake in the neck of the pancreas with a standardized uptake value of 12. Despite negative intraoperative pancreatic palpation and ultrasound, the patient underwent an extended distal pancreatectomy with normalization of biochemical levels and resolution of her symptoms. Pathology showed four subcentimeter neuroendocrine tumors that were positive for insulin, consistent with a diagnosis of multiple microadenomas.
  
  
  
  Multiple microadenomas are a rare cause of hyperinsulinemic hypoglycemia and localization, and resection of these tumors may be facilitated by multimodal imaging.
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Bruna
authors: B
authors: Babic
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Xavier
authors: X
authors: Keutgen
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Pavel
authors: P
authors: Nockel
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Markke
authors: M
authors: Miettinen
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Corina
authors: C
authors: Millo
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Peter
authors: P
authors: Herscovitch
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Dhaval
authors: D
authors: Patel
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Naris
authors: N
authors: Nilubol
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Craig
authors: C
authors: Cochran
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Phillip
authors: P
authors: Gorden
authors: Endocrine Oncology Branch (B.B., X.K., P.N., D.P., N.N., E.K.), and Laboratory of Pathology (M.M.), National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892; PET Department (C.M., P.H.), National Institutes of Health Clinical Center, Bethesda, Maryland 20814; and National Institute of Diabetes and Digestive and Kidney Diseases (C.C., P.G.), National Institutes of Health, Bethesda, Maryland 20892.
authors: Electron
authors: E
authors: Kebebew
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007340:Insulinoma / Q000097:blood / Q000000981:diagnostic imaging* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D064847:Multimodal Imaging; D010180:Pancreatectomy; D010190:Pancreatic Neoplasms / Q000097:blood / Q000000981:diagnostic imaging* / Q000601:surgery; D000072078:Positron Emission Tomography Computed Tomography