title: Diffusion-Weighted MRI Reflects Proliferative Activity in Primary CNS Lymphoma.
abstract: OBJECTIVE
  To investigate if apparent diffusion coefficient (ADC) values within primary central nervous system lymphoma correlate with cellularity and proliferative activity in corresponding histological samples.
  
  
  METHODS
  Echo-planar diffusion-weighted magnetic resonance images obtained from 21 patients with primary central nervous system lymphoma were reviewed retrospectively. Regions of interest were drawn on ADC maps corresponding to the contrast enhancing parts of the tumors. Biopsies from all 21 patients were histologically analyzed. Nuclei count, total nuclei area and average nuclei area were measured. The proliferation index was estimated as Ki-67 positive nuclei divided by total number of nuclei. Correlations of ADC values and histopathologic parameters were determined statistically.
  
  
  RESULTS
  Ki-67 staining revealed a statistically significant correlation with ADCmin (r = -0.454, p = 0.038), ADCmean (r = -0.546, p = 0.010) and ADCmax (r = -0.515, p = 0.017). Furthermore, ADCmean correlated in a statistically significant manner with total nucleic area (r = -0.500, p = 0.021).
  
  
  CONCLUSIONS
  Low ADCmin, ADCmean and ADCmax values reflect a high proliferative activity of primary cental nervous system lymphoma. Low ADCmean values-in concordance with several previously published studies-indicate an increased cellularity within the tumor.
authors: Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany.
authors: Stefan
authors: http://orcid.org/0000-0003-2846-5443
authors: S
authors: Schob
authors: Department of Radiology, Martin Luther University of Halle-Wittenberg, Halle-Wittenberg, Germany.
authors: Jonas
authors: J
authors: Meyer
authors: Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany.
authors: Matthias
authors: M
authors: Gawlitza
authors: Department of Neuropathology, University Hospital Leipzig, Leipzig, Germany.
authors: Clara
authors: C
authors: Frydrychowicz
authors: Department of Neuropathology, University Hospital Leipzig, Leipzig, Germany.
authors: Wolf
authors: W
authors: Müller
authors: Department of Neurosurgery, University Hospital Leipzig, Leipzig, Germany.
authors: Matthias
authors: M
authors: Preuss
authors: Department of Radiology, McGill University Health Center, Montreal General Hospital, Montreal, Canada.
authors: Lionel
authors: L
authors: Bure
authors: Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany.
authors: Ulf
authors: U
authors: Quäschling
authors: Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany.
authors: Karl-Titus
authors: KT
authors: Hoffmann
authors: Department of Diagnostic and Interventional Radiology, University Hospital Leipzig, Leipzig, Germany.
authors: Alexey
authors: A
authors: Surov
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016543:Central Nervous System Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008223:Lymphoma / Q000175:diagnosis* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D019394:Ki-67 Antigen