Occurrence of giant focal forms of congenital hyperinsulinism with incorrect visualization by (18) F DOPA-PET/CT scanning.

CONTEXT: Congenital hyperinsulinism (CHI) is a rare disease characterized by severe hypoglycaemic episodes due to pathologically increased insulin secretion from the pancreatic beta cells. When untreated, CHI might result in irreversible brain damage and death. Currently, two major subtypes of CHI are known: a focal form, associated with local distribution of affected beta cells and a nonfocal form, affecting every single beta cell. The identification of focal forms is important, as the patients can be cured by limited surgery. (18) F DOPA-PET/CT is an established non-invasive approach to differentiate focal from nonfocal CHI. OBJECTIVE: The purpose of this study was to identify possible limitations of (18) F DOPA-PET/CT scan in patients with focal forms nonfocal CHI. DESIGN: A retrospective chart review of 32 patients (from 2008 through 2013) who underwent (18) F DOPA-PET/CT and partial pancreatectomy for focal CHI at the reference centres in Berlin, Germany and London, UK. RESULTS: In most cases (n = 29, 90·7%), (18) F DOPA-PET/CT was sufficient to localize the complete focal lesion. However, in some patients (n = 3, 9·3%), (18) F DOPA-PET/CT wrongly visualized only a small portion of the focal lesion. In this group of patients, a so-called 'giant focus' was detected in histopathological analysis during the surgery. CONCLUSIONS: Our data show that in most patients with focal CHI (18) F DOPA-PET/CT correctly predicts the size and anatomical localisation of the lesion. However, in those patients with a 'giant focal' lesion (18) F DOPA-PET/CT is unreliable for correct identification of 'giant focus' cases.

Evaluation of [18F]fluoro-L-DOPA positron emission tomography-computed tomography for surgery in focal congenital hyperinsulinism.

CONTEXT: In congenital hyperinsulinism (CHI), the identification and precise localization of a focal lesion is essential for successful surgery. OBJECTIVE: Our objective was to evaluate the predictive value and accuracy of integrated [18F]fluoro-L-DOPA ([18F]FDOPA) positron emission tomography (PET)-computed tomography (CT) for the surgical therapy of CHI. DESIGN: This was an observational study. SETTING: The study was performed in the Department of Pediatric Surgery at a university hospital. PATIENTS: From February 2005 to September 2007, 10 children with the clinical signs of CHI and an increased radiotracer uptake in a circumscribed area of the pancreas in the [18F]FDOPA PET-CT were evaluated. INTERVENTIONS: Guided by the [18F]FDOPA PET-CT report, all children underwent partial pancreatic resection, in two cases twice. MAIN OUTCOME MEASURES: Correlation of the anatomical findings at surgery with the report of the [18F]FDOPA PET-CT, and the results of surgery and clinical outcome were determined. RESULTS: In nine children the intraoperative situation corresponded exactly to the description of the [18F]FDOPA PET-CT. A limited resection of the pancreas was curative in eight cases at the first surgery, in one case at the second intervention. We observed no diabetes mellitus or exocrine insufficiency in the follow up so far. In one child, hypoglycemia persisted even after two partial resections of the pancreatic head. Histological analysis finally revealed an atypical intermediate form of CHI. CONCLUSIONS: The integrated [18F]FDOPA PET-CT is accurate to localize the lesion in focal CHI and is a valuable tool to guide the surgeon in limited pancreatic resection.

Visualization of the focus in congenital hyperinsulinism by intraoperative sonography.

In surgery for focal congenital hyperinsulinism (CHI), the identification and complete resection of the focus without collateral damage is of utmost importance. In a pilot study we applied intra-abdominal high-frequency sonography during surgery for focal CHI in 2 infants. The focus could be identified, its relation to the pancreatic and common bile duct could be shown, and the typical octopus-like tentacles could be demonstrated. In one case the resection was successful; in the other it was not. These preliminary results suggest that intraoperative sonography could be a valuable tool in the surgical therapy of focal CHI and warrants further evaluation in a clinical study.