title: Early response of hepatic malignancies to locoregional therapy-value of diffusion-weighted magnetic resonance imaging and proton magnetic resonance spectroscopy.
abstract: OBJECTIVE
  The objective of our study was to determine the usefulness of the diffusion-weighted magnetic resonance imaging and proton magnetic resonance spectroscopy (H-MRS) of hepatic malignancies for the assessment of response to locoregional treatment.
  
  
  METHODS
  Forty-four patients (29 men; mean age, 58 years) with hepatic malignancies were treated locally. Magnetic resonance imaging examinations obtained before and at 1 and 6 months after transarterial chemoembolization were analyzed retrospectively. Imaging criteria included change in tumor size, percentage of enhancement in the arterial and portal venous phases, diffusion-weighted magnetic resonance imaging apparent diffusion coefficients, and choline concentration by quantitative H-MRS. Response to treatment was grouped according to RECIST (Response Evaluation Criteria in Solid Tumors) and European Association for the Study of the Liver (EASL) criteria based on magnetic resonance imaging at 6 months after treatment. Statistical analysis used paired t test, Fisher exact test, and univariate and multivariate Cox proportional hazards models.
  
  
  RESULTS
  Before treatment, the median tumor diameter was 6 cm; at 6 months after treatment, median tumor diameter was 5.1 cm. According to RECIST and EASL, 66% of the patients achieved partial response, 31% had stable disease, and 3% of the patients showed progressive disease. One month after transarterial chemoembolization, apparent diffusion coefficient increased (P < 0.14), and mean choline concentration of the tumors decreased (P < 0.008).
  
  
  CONCLUSIONS
  Diffusion-weighted imaging and hepatic choline levels by H-MRS could predict response to locoregional therapy.
authors.affiliation: Russell H Morgan Department of Radiology and Radiology Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Susanne
authors.initials: S
authors.lastname: Bonekamp
authors.forename: Jialin
authors.initials: J
authors.lastname: Shen
authors.forename: Nouha
authors.initials: N
authors.lastname: Salibi
authors.forename: Hong C
authors.initials: HC
authors.lastname: Lai
authors.forename: Jeff
authors.initials: J
authors.lastname: Geschwind
authors.forename: Ihab R
authors.initials: IR
authors.lastname: Kamel
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002794:Choline / Q000032:analysis*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000628:therapy*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D002794:Choline