Characterization of hyperinsulinism in infancy assessed with PET and 18F-fluoro-L-DOPA.
Hyperinsulinism (HI) of infancy is a neuroendocrine disease secondary to either focal adenomatous hyperplasia or a diffuse abnormality of insulin secretion of the pancreas. HI with focal lesions can revert by selective surgical resection in contrast to the diffuse form, which requires subtotal pancreatectomy when resistant to medical treatment. Neuroendocrine diseases are a heterogeneous group of entities with the ability to take up amine precursors and to convert them into biogenic amines. Therefore, the aim of this study was (a) to evaluate the use of PET with 18F-fluoro-L-dihydroxyphenylalanine (18F-fluoro-L-DOPA) and (b) to distinguish between focal and diffuse HI.


METHODS
Fifteen patients (11 boys, 4 girls) with neonatal HI were enrolled in this study. All patients fasted for at least 6 h before the PET examination and their medication was discontinued for at least 72 h. The examination was performed under light sedation (pentobarbital associated with or without chloral). The dynamic acquisition started 45-65 min after the injection of 18F-fluoro-L-DOPA (4.0 MBq/kg weight). Four or 6 scans of 5 min each (2 or 3 steps according to the height of the patient) were acquired from the neck to the upper legs.


RESULTS
An abnormal focal pancreatic uptake of 18F-fluoro-L-DOPA was observed in 5 patients, whereas a diffuse uptake of the radiotracer was observed in the pancreatic area of the other patients. All patients with focal radiotracer uptake and also 4 of 10 patients with pancreatic diffuse radiotracer accumulation, unresponsive to medical treatment, underwent surgery. The histopathologic results confirmed the PET findings--that is, focal versus diffuse HI.


CONCLUSIONS
The results of this study suggest that 18F-fluoro-L-DOPA could be an accurate noninvasive technique to distinguish between focal and diffuse forms of HI.
Ribeiro
Maria-João
MJ
Service Hospitalier Frédéric Joliot, Département de Recherche Médicale, Direction des Sciences du Vivant, Commissariat à l'Energie Atomique, Orsay, France. ribeiro@shfj.cea.fr
De Lonlay
Pascale
P
Delzescaux
Thierry
T
Boddaert
Nathalie
N
Jaubert
Francis
F
Bourgeois
Sandrine
S
Dollé
Frédéric
F
Nihoul-Fékété
Claire
C
Syrota
André
A
Brunelle
Francis
F
D044903:Congenital Hyperinsulinism / Q000145:classification / Q000000981:diagnostic imaging* / Q000378:metabolism*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000378:metabolism* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009928:Organ Specificity; D010179:Pancreas / Q000000981:diagnostic imaging* / Q000378:metabolism*; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012720:Severity of Illness Index; D014018:Tissue Distribution; D014915:Whole-Body Counting / Q000379:methods
D019275:Radiopharmaceuticals; C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine