Clinical and imaging features of focal nodular hyperplasia in children.
OBJECTIVE
The purpose of this article is to review the clinical and imaging features of focal nodular hyperplasia (FNH) developed in children.


METHODS
At a single institution, pediatric patients who underwent imaging studies and who had pathologically proven FNH were studied. Clinical characteristics, including presenting symptoms and signs and the presence of underlying disease, were reviewed from the medical records. Imaging features of FNHs, including the number, size, ultrasound echogenicity and vascularity, CT attenuation, MRI signal intensity and enhancement pattern, and the presence of a central scar, were evaluated.


RESULTS
Twenty-five patients (11 boys and 14 girls; median age, 8.6 years) were found to have a solitary (n = 23) or multiple (n = 2) FNH lesions with a mean size of 4.9 cm (range, 1-10 cm). Multiple lesions were associated with small size of the lesions and history of malignancy treated by chemotherapy. Most patients were asymptomatic (n = 22). Biliary atresia was the most common underlying disease (n = 5). On ultrasound, FNHs most commonly appeared to be isoechoic and hypervascular. On dynamic CT and MRI, strong enhancement on the arterial phase and becoming isoattenuated or of isointense signal intensity on the portal or delayed phase was common. A central scar was usually noted in large lesions in about half the cases.


CONCLUSIONS
Pediatric FNH is uncommon and usually is found incidentally in otherwise healthy children. However, it may occur in children who have underlying diseases, including biliary atresia. In addition, it can be encountered during surveillance of childhood cancer survivors with less common imaging features, including lack of a central scar and multiplicity.
1 All authors: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Ku, Seoul 135-710, Korea.
Dong Ik
DI
Cha
So-Young
SY
Yoo
Ji Hye
JH
Kim
Tae Yeon
TY
Jeon
Hong
H
Eo
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003952:Diagnostic Imaging; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D008297:Male; D012189:Retrospective Studies