title: Manganese-enhanced MRI predicts the histological grade of hepatocellular carcinoma in potential surgical candidates.
abstract: OBJECTIVE
  To evaluate the role of manganese-enhanced magnetic resonance (Mn-MRI) in predicting tumour differentiation prior to liver transplant or resection for hepatocellular carcinoma (HCC).
  
  
  METHODS
  The inclusion criteria were patients with HCC who underwent Mn-MRI prior to transplantation or resection from 2001-2008. T1-weighted MRI images were acquired at 0 and 24h after manganese dipyridoxal diphosphate (MnDPDP) intravenous contrast medium and reviewed prospectively. Manganese retention at 24h was correlated with tumour differentiation and disease-free survival.
  
  
  RESULTS
  Eighty-six patients underwent Mn-MRI (transplantation 60, resection 26); 114/125 lesions (91%) that were arterialised as evidenced at computed tomography (CT) and had manganese uptake on MRI were HCC. There were 11 false positives (9%) that were regenerative nodules. Ten of fourteen non-manganese-retaining HCC (71%) were poorly differentiated, compared with only 13/114 manganese-retaining HCC (11%) (p<0.0001). Sensitivity, specificity, positive and negative predictive values of non-retention of MnDPDP in predicting poorly differentiated tumours were 0.43, 0.96, 0.71 and 0.88. Median disease-free survival of patients with non-manganese-retaining HCC was less than for patients with manganese-retaining HCC (14±5 months versus 39±3 months, log rank p=0.025).
  
  
  CONCLUSIONS
  Non-manganese-retaining HCCs are likely to be poorly differentiated and have a poor prognosis. Manganese-enhanced MRI appears to have a role in preoperative assessment of HCC and warrants further evaluation.
authors.affiliation: Institute of Liver Studies, King's College Hospital, London, UK.
authors.forename: R P
authors.initials: RP
authors.lastname: Sutcliffe
authors.forename: D
authors.initials: D
authors.lastname: Lewis
authors.forename: P A
authors.initials: PA
authors.lastname: Kane
authors.forename: B C
authors.initials: BC
authors.lastname: Portmann
authors.forename: J G
authors.initials: JG
authors.lastname: O'Grady
authors.forename: J B
authors.initials: JB
authors.lastname: Karani
authors.forename: M
authors.initials: M
authors.lastname: Rela
authors.forename: N D
authors.initials: ND
authors.lastname: Heaton
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D003287:Contrast Media / Q000493:pharmacokinetics; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D016031:Liver Transplantation; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008345:Manganese / Q000493:pharmacokinetics; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D008345:Manganese