title: Diffusion-weighted MRI characteristics of the cerebral metastasis to brain boundary predicts patient outcomes.
abstract: BACKGROUND
  Diffusion-weighted MRI (DWI) has been used in neurosurgical practice mainly to distinguish cerebral metastases from abscess and glioma. There is evidence from other solid organ cancers and metastases that DWI may be used as a biomarker of prognosis and treatment response. We therefore investigated DWI characteristics of cerebral metastases and their peritumoral region recorded pre-operatively and related these to patient outcomes.
  
  
  METHODS
  Retrospective analysis of 76 cases operated upon at a single institution with DWI performed pre-operatively at 1.5T. Maps of apparent diffusion coefficient (ADC) were generated using standard protocols. Readings were taken from the tumor, peritumoral region and across the brain-tumor interface. Patient outcomes were overall survival and time to local recurrence.
  
  
  RESULTS
  A minimum ADC greater than 919.4 × 10(-6) mm(2)/s within a metastasis predicted longer overall survival regardless of adjuvant therapies. This was not simply due to differences between the types of primary cancer because the effect was observed even in a subgroup of 36 patients with the same primary, non-small cell lung cancer. The change in diffusion across the tumor border and into peritumoral brain was measured by the "ADC transition coefficient" or ATC and this was more strongly predictive than ADC readings alone. Metastases with a sharp change in diffusion across their border (ATC >0.279) showed shorter overall survival compared to those with a more diffuse edge. The ATC was the only imaging measurement which independently predicted overall survival in multivariate analysis (hazard ratio 0.54, 95% CI 0.3 - 0.97, p = 0.04).
  
  
  CONCLUSIONS
  DWI demonstrates changes in the tumor, across the tumor edge and in the peritumoral region which may not be visible on conventional MRI and this may be useful in predicting patient outcomes for operated cerebral metastases.
authors.affiliation: Department of Neurosurgery, The Walton Centre NHS Foundation Trust, Liverpool, UK. rzakaria@nhs.net.
authors.forename: Rasheed
authors.initials: R
authors.lastname: Zakaria
authors.forename: Kumar
authors.initials: K
authors.lastname: Das
authors.forename: Mark
authors.initials: M
authors.lastname: Radon
authors.forename: Maneesh
authors.initials: M
authors.lastname: Bhojak
authors.forename: Philip R
authors.initials: PR
authors.lastname: Rudland
authors.forename: Vanessa
authors.initials: V
authors.lastname: Sluming
authors.forename: Michael D
authors.initials: MD
authors.lastname: Jenkinson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000473:pathology* / Q000556:secondary*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
references.citation: Int J Radiat Oncol Biol Phys. 2006 Sep 1;66(1):187-94
references.pmid: 16814946
references.citation: Radiology. 2004 Jul;232(1):221-8
references.pmid: 15220505
references.citation: J Gastrointest Oncol. 2012 Mar;3(1):11-8
references.pmid: 22811865
references.citation: Surg Neurol Int. 2013 May 02;4(Suppl 4):S209-19
references.pmid: 23717792
references.citation: Cancer. 1996 Oct 15;78(8):1781-8
references.pmid: 8859192
references.citation: PLoS One. 2013;8(2):e55464
references.pmid: 23393579
references.citation: AJNR Am J Neuroradiol. 2001 May;22(5):969-76
references.pmid: 11337344
references.citation: Mayo Clin Proc. 1987 Jun;62(6):450-9
references.pmid: 3553757
references.citation: Invest Radiol. 2014 Jul;49(7):485-90
references.pmid: 24619211
references.citation: Cancer Imaging. 2012 Aug 10;12:245-52
references.pmid: 22935843
references.citation: Eur J Radiol. 2011 Nov;80(2):412-7
references.pmid: 20580505
references.citation: AJNR Am J Neuroradiol. 2011 Oct;32(9):1646-51
references.pmid: 21835939
references.citation: J Neurosurg. 2010 Aug;113(2):181-9
references.pmid: 20035574
references.citation: Clin Neuropathol. 2001 Jan-Feb;20(1):38-42
references.pmid: 11220694
references.citation: Eur Radiol. 2004 Oct;14(10):1909-17
references.pmid: 15221264
references.citation: Int J Cancer. 2014 Feb 15;134(4):885-96
references.pmid: 23913394
references.citation: Br J Radiol. 2011 Dec;84 Spec No 2:S213-26
references.pmid: 22433831
references.citation: Nat Med. 2010 Jan;16(1):116-22
references.pmid: 20023634
references.citation: J Magn Reson Imaging. 2007 Dec;26(6):1405-12
references.pmid: 17968881
references.citation: Br J Radiol. 2011 Dec;84 Spec No 2:S159-67
references.pmid: 22433826
references.citation: Clin Exp Metastasis. 2013 Apr;30(4):357-68
references.pmid: 23076770
references.citation: Magn Reson Imaging. 2014 Apr;32(3):291-6
references.pmid: 24462300
references.citation: Int J Radiat Oncol Biol Phys. 2008 Feb 1;70(2):510-4
references.pmid: 17931798
references.citation: Eur J Cancer. 2011 Mar;47(5):649-55
references.pmid: 21196112
references.citation: Cancer Res. 2014 Apr 1;74(7):1902-12
references.pmid: 24491802
references.citation: Int J Radiat Oncol Biol Phys. 1997 Mar 1;37(4):745-51
references.pmid: 9128946
references.citation: Neurosurgery. 2005 Nov;57(5 Suppl):S10-23; discusssion S1-4
references.pmid: 16237282
references.citation: Eur J Radiol. 2006 Jun;58(3):394-403
references.pmid: 16527438
references.citation: AJNR Am J Neuroradiol. 2010 Jan;31(1):60-6
references.pmid: 19729544
references.citation: Eur J Radiol. 2010 Apr;74(1):117-20
references.pmid: 19359117
references.citation: Trends Pharmacol Sci. 2012 Jul;33(7):405-12
references.pmid: 22633092
references.citation: Eur J Paediatr Neurol. 2013 May;17(3):302-7
references.pmid: 23273960
references.citation: AJR Am J Roentgenol. 2011 Jan;196(1):71-6
references.pmid: 21178049
references.citation: Eur Radiol. 2012 Nov;22(11):2319-27
references.pmid: 22653281
references.citation: AJNR Am J Neuroradiol. 2012 Nov;33(10):1907-12
references.pmid: 22743640
references.citation: Clin Cancer Res. 2004 Sep 15;10(18 Pt 1):6222-30
references.pmid: 15448011
references.citation: Int J Radiat Oncol Biol Phys. 2011 Nov 15;81(4):1075-80
references.pmid: 20971574
references.citation: Neuroimage. 2009 Feb 1;44(3):653-60
references.pmid: 18951985
references.citation: AJNR Am J Neuroradiol. 2014 Mar;35(3):439-44
references.pmid: 24052506
references.citation: AJNR Am J Neuroradiol. 2006 Aug;27(7):1419-25
references.pmid: 16908550
references.citation: AJNR Am J Neuroradiol. 2014 Feb;35(2):379-85
references.pmid: 24029391
references.citation: AJR Am J Roentgenol. 1998 Dec;171(6):1487-90
references.pmid: 9843275
references.citation: Br J Radiol. 2005 Jun;78(930):533-7
references.pmid: 15900059
references.citation: J Exp Clin Cancer Res. 2004 Mar;23(1):39-45
references.pmid: 15149149
references.citation: Neuroradiology. 2004 Aug;46(8):619-27
references.pmid: 15243726
references.citation: Eur Radiol. 2011 Dec;21(12):2567-74
references.pmid: 21822946
references.citation: Neuro Oncol. 2013 Dec;15(12):1664-72
references.pmid: 24084410
references.citation: NMR Biomed. 2011 Jan;24(1):54-60
references.pmid: 20665905