title: Atypical focal nodular hyperplasia of the liver.
abstract: BACKGROUND
  Focal nodular hyperplasia, a benign hepatic tumor, is usually asymptomatic. However, rarely the entity can cause symptoms, mandating intervention.
  
  
  METHODS
  We present a case of focal nodular hyperplasia of the liver, which caused a considerable diagnostic dilemma due to its atypical presentation.
  
  
  RESULTS
  A 29-year-old woman presented with a 15-year history of a progressively increasing mass in the right upper quadrant which was associated with pain and emesis. Examination showed a firm, mobile mass palpable below the right subcostal margin. A computed tomography scan of the abdomen showed an exophytic mass arising from hepatic segments III and IVb. Trucut biopsy of the hepatic mass was equivocal. Angiography showed a vascular tumor that was supplied by a tortuous branch of the proper hepatic artery. Surgical intervention for removal of the mass was undertaken. Intra-operatively, two large discrete tumors were found and completely resected. Histopathological examination showed features consistent with focal nodular hyperplasia.
  
  
  CONCLUSIONS
  This description of an unusual case of focal nodular hyperplasia of the liver highlights the point that the diagnosis of otherwise benign hepatic tumors may be difficult despite extensive work-up in some cases.
authors.affiliation: Section of General Surgery, Department of Surgery, Aga Khan University, Stadium Road, Karachi 74800, Pakistan. khan.rizwan@aku.edu
authors.forename: Muhammad Rizwan
authors.initials: MR
authors.lastname: Khan
authors.forename: Taimur
authors.initials: T
authors.lastname: Saleem
authors.forename: Tanveer Ul
authors.initials: TU
authors.lastname: Haq
authors.forename: Kanwal
authors.initials: K
authors.lastname: Aftab
mesh_terms: D000328:Adult; D000792:Angiography; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed