Focal nodular hyperplasia or focal nodular hyperplasia-like lesions of the liver: a special emphasis on diagnosis.
OBJECTIVE
Focal nodular hyperplasia (FNH) and FNH-like lesions are hypervascular masses that can mimic hepatocellular carcinoma (HCC). We have investigated the clinical, radiological and pathological features of FNH and FNH-like lesions of the liver, with particular focus on the aspect of diagnosis.


METHODS
A total of 84 patients, 77 with pathologically-proven FNH and seven with FNH-like lesions of the liver, were analyzed retrospectively.


RESULTS
Of the 84 patients, seven had underlying liver cirrhosis, including two with Budd-Chiari syndrome and one with cardiac cirrhosis. These cases were therefore classified as having FNH-like lesions. Two of the remaining 77 patients without underlying liver cirrhosis were positive for hepatitis B surface antigen. Seven of 50 (14.0%) patients evaluated by four-phase computed tomography (CT) showed portal or delayed washout, and three of 28 (10.7%) patients analyzed by three-phase CT showed washout on the portal phase. Collectively, three of nine (33.3%) patients with risk factors for HCC could have been wrongly diagnosed with HCC based on the non-invasive diagnostic criteria for HCC. A central scar was observed in 30 patients (35.7%) radiologically. Among 62 patients who underwent percutaneous needle biopsy, four patients (6.5%) were misdiagnosed as having HCC and two patients (3.2%) had inconclusive results by a first needle biopsy.


CONCLUSIONS
The presence of a hepatic lesion with arterial hypervascularity and/or portal/delayed washout is not necessarily diagnostic of HCC, particularly in patients without risk factors for HCC. These radiological findings can also occur in cirrhotic patients with FNH-like lesions, including those with hepatic outflow obstruction.
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, Seoul, Korea.
Ji Young
JY
Choi
Han Chu
HC
Lee
Ji Hye
JH
Yim
Ju Hyun
JH
Shim
Young-Suk
YS
Lim
Yong Moon
YM
Shin
Eun Sil
ES
Yu
Dong Jin
DJ
Suh
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D003951:Diagnostic Errors; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000145:classification / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D006801:Humans; D008099:Liver / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology*; D008103:Liver Cirrhosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D056910:Republic of Korea; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D055815:Young Adult