A pediatric case of multiple hepatic focal nodular hyperplasia-like lesions presenting as atypical imaging and histopathological findings

Abstract

We encountered the case of a 10-year-old girl presenting with multiple hepatic focal nodular hyperplasia (FNH)-like lesions, which were difficult to differentiate from hepatocellular carcinoma (HCC) because of their atypical presentation. She was referred to our institution for an incidentally detected multiple liver mass during the follow-up for thigh pain. Enhanced MRI with gadolinium ethoxybenzyl diethy­lenetriamine-pentaacetic acid (Gd-EOB-DTPA) showed compatible observation in most nodules. However, a mass in S3 showed hypointensity in the hepatocellular phase, which is characteristic of HCC. We performed laparoscopic tumorectomy to rule out malignancy. A histopathological study showed benign hyperplastic lesions, but further classification was difficult. Thus, our final diagnosis was FNH-like lesions.
FNH-like lesions are hyperplastic lesions caused by a vascular abnormality similar to a typical FNH, although their features are not compatible with those of FNH. This disease may be difficult to distinguish from FNH or HCC because the imaging findings as well as the histopathological findings are atypical. We have to consider this disease when we see an imaging study indicating HCC, despite a benign clinical picture.