[18F]-DOPA PET/CT imaging in congenital hyperinsulinism-first 5 years of the Australian experience

Abstract

In the southern hemisphere, [18F]-DOPA PET/CT (Positron Emission Tomography/Computed Tomography) of the pancreas became available in Brisbane, Australia in early 2010. This may enable preoperative distinction of focal and diffuse forms of Congenital Hyperinsulinism (CH) without the challenges of travel to an overseas centre. Objectives: Determine the clinical utility of [18F]-DOPA PET/CT in distinguishing focal from diffuse disease in patients with CH. Methods: Case records were reviewed for clinical details, metabolic and genetic investigations, PET/CT result, histology (if surgery performed) and clinical outcome. Results: Fifteen PET/CT scans had been performed. Patients were 3 weeks to 4 years of age, with 10 patients ≤6 months of age. Eight patients had genetics suggestive of focal disease (5 with paternal ABCC8 and 3 with paternal KCNJ11 mutations), of which PET/CT indicated focal disease in 5 (2 in head, 2 in head / uncinate process, 1 in neck). Focal lesions were identified in all four who had surgery (3 paternal ABCC8, 1 paternal KCNJ11 mutations). Medical support was able to be withdrawn for these patients. Seven patients had genetics suggestive of diffuse disease (2 homozygous ABCC8, 1 heterozygous GLUD1, 1 mosaic whole genome uniparental disomy) or non-informative genetics (1 heterozygous de novo ABCC8, 1 negative for ABCC8, KCNJ11, GLUD1, GK and HNF4a). Diffuse histology was confirmed in the 2 infants who had surgery (near-total pancreatectomy). Conclusions: In the 6 patients who proceeded to surgery, PET/CT scanning demonstrated 100% accuracy in discriminating focal from diffuse disease. The accuracy of PET/CT cannot be confirmed by histology in the remaining 9 patients who are medically managed. PET/CT scanning was instrumental, in combination with genetic background, in facilitating targeted resection of focal lesions and enhancing confidence in performing a near-total resection in those with diffuse disease.L720732052015-11-20 <br />