title: [Lymphoma-simulating presentation of focal nodular hyperplasia (FNH) of the liver].
abstract: A 51-year-old woman, who had taken oral contraceptive drugs for 11 years, was referred to our Unit for examination of an asymptomatic 3.6 x 4.1 cm hypoechoic liver mass found by ultrasound examination carried out in the course of gynecological screening.
  
  
  METHODS
  Laboratory evaluation revealed mild elevated liver enzymes. Computed tomography exhibited a hypervascularized lesion in segment 4 of the liver resembling a hemangioma or focal nodular hyperplasia but FNH was favored since magnetic resonance imaging showed a central scar within the hepatic lesion. Hepatobiliary scintigraphy was not typical thus an ultrasound-guided needle biopsy was performed. Histological examination revealed lymphoma-like infiltrates close to normal liver cells. However, the molecular biological examination showed oligoclonality of the infiltrating T-cells. Blood examinations, bone-marrow punctuation and CT thorax scan did not show any other lymphoma-like lesion.
  
  
  METHODS
  After 5, 10 and 15 months the untreated patient was re-examined by MRI. The focal lesion showed an unchanged size and again a FNH-typical imaging. Liver-specific contrast enhancement was not suggestive for lymphoma. The lymphocytes were interpreted as an atypical lymphoid inflammatory infiltrate of a non-neoplastic lesion of the liver.
  
  
  CONCLUSIONS
  The focal nodular hyperplasia can be a very difficult diagnosis in imaging and histopathological examinations. The lymphoma of the liver can be a rare but possible differential diagnosis.
authors.affiliation: Johannes-Gutenberg-Universitätsklinik Mainz, Medizinische Klinik und Poliklinik.
authors.forename: D
authors.initials: D
authors.lastname: Schmitz
authors.forename: H H
authors.initials: HH
authors.lastname: Köhler
authors.forename: C P
authors.initials: CP
authors.lastname: Heussel
authors.forename: H F
authors.initials: HF
authors.lastname: Löhr
authors.forename: P R
authors.initials: PR
authors.lastname: Galle
mesh_terms: D001707:Biopsy, Needle; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000175:diagnosis* / Q000473:pathology; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D008099:Liver / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis* / Q000473:pathology; D008479:Mediastinal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008875:Middle Aged