title: RF Ablation of Giant Hemangiomas Inducing Acute Renal Failure: A Report of Two Cases.
abstract: OBJECTIVE
  In patients that require treatment for hepatic giant cavernous hemangiomas (GCH), radiofrequency ablation (RFA) has been suggested to represent a safe and effective alternative to invasive surgery. In a recent report of bipolar RFA, using two expandable needle electrodes, was uneventfully performed in patients with large GCH (>10 cm). The objective of this report is to present two cases in which bipolar RFA of symptomatic GCH was complicated by acute kidney injury.
  
  
  METHODS
  In 2015 we treated two patients for very large symptomatic GCH (15.7 and 25.0 cm) with bipolar RFA during open laparotomy.
  
  
  RESULTS
  In both patients the urine showed a red-brown discoloration directly after the ablation. They became anuric and presented with progressive dyspnea, tachypnea, and tachycardia, requiring hemodialysis for a period of 1 month in one case. Lab results revealed hemepigment-induced acute kidney. Both patients fully recovered and both showed a complete relief of symptoms at 3 months following the procedure.
  
  
  CONCLUSIONS
  RFA for large GCHs can cause hemepigment-induced acute kidney injury due to massive intravascular hemolysis. The presented cases suggest that caution is warranted and advocate an upper limit regarding the volume of GCHs that can be safely ablated.
authors.affiliation: Departments of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands. a.vantilborg@vumc.nl.
authors.forename: Aukje A J M
authors.initials: AAJM
authors.lastname: van Tilborg
authors.affiliation: Department of Nefrology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Helena F
authors.initials: HF
authors.lastname: Dresselaars
authors.affiliation: Departments of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands.
authors.forename: Hester J
authors.initials: HJ
authors.lastname: Scheffer
authors.affiliation: VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Karin
authors.initials: K
authors.lastname: Nielsen
authors.affiliation: Department of Surgical Oncology, Gelderse Vallei Hospital, Ede, Amsterdam, The Netherlands.
authors.forename: Colin
authors.initials: C
authors.lastname: Sietses
authors.affiliation: VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Petrousjka M
authors.initials: PM
authors.lastname: van den Tol
authors.affiliation: Departments of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands.
authors.forename: Martijn R
authors.initials: MR
authors.lastname: Meijerink
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000209:etiology*; D000328:Adult; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006392:Hemangioma, Cavernous / Q000601:surgery*; D006801:Humans; D008113:Liver Neoplasms / Q000601:surgery*; D008875:Middle Aged; D016896:Treatment Outcome
keywords: Acute kidney injury; Giant cavernous hemangioma; Hemolysis; Radiofrequency ablation