title: Contribution of Histopathologic Tissue Composition to Quantitative MR Spectroscopy and Diffusion-weighted Imaging of the Prostate.
abstract: OBJECTIVE
  To determine associations of metabolite levels derived from magnetic resonance (MR) spectroscopic imaging (ie, hydrogen 1 [(1)H] MR spectroscopic imaging) and apparent diffusion coefficients (ADCs) from diffusion-weighted imaging with prostate tissue composition assessed by digital image analysis of histologic sections.
  
  
  METHODS
  Institutional ethical review board approved this retrospective study and waived informed consent. Fifty-seven prostate cancer patients underwent an MR examination followed by prostatectomy. One hematoxylin and eosin-stained section of the resected prostate per patient was digitized and computationally segmented into nuclei, lumen, and combination of epithelial cytoplasm and stroma. On each stained section, regions of interest (ROIs) were chosen and matched to the corresponding ADC map and (1)H MR spectroscopic imaging voxels. ADC and two metabolite ratios (citrate [Cit], spermine [Spm], and creatine [Cr] to choline [Cho] and Cho to Cr plus Spm) were correlated with percentage areas of nuclei, lumen, and cytoplasm and stroma for peripheral zone (PZ), transition zone (TZ), and tumor tissue in both zones of the prostate by using a linear mixed-effect model and Spearman correlation coefficient (ρ).
  
  
  RESULTS
  ADC and (Cit + Spm + Cr)/Cho ratio showed positive correlation with percentage area of lumen (ρ = 0.43 and 0.50, respectively) and negative correlation with percentage area of nuclei (ρ = -0.29 and -0.26, respectively). The Cho/(Cr + Spm) ratio showed negative association with percentage area of lumen (ρ = -0.40) and positive association with area of nuclei (ρ = 0.26). Percentage areas of lumen and nuclei, (Cit + Spm + Cr)/Cho ratio, and ADC were significantly different (P < .001) between benign PZ (23.7 and 7.7, 8.83, and 1.58 × 10(-3) mm(2)/sec, respectively) and tumor PZ tissue (11.4 and 12.5, 5.13, and 1.20 × 10(-3) mm(2)/sec, respectively). These parameters were also significantly different between benign TZ (20.0 and 8.2, 6.50, and 1.26 × 10(-3) mm(2)/sec, respectively) and tumor TZ tissue (9.8 and 11.2, 4.36, and 1.03 × 10(-3) mm(2)/sec, respectively).
  
  
  CONCLUSIONS
  The observed correlation of (Cit + Spm + Cr)/Cho ratio and ADC of the prostate with its tissue composition indicates that components of this composition, such as percentage luminal area, contribute to the value of these MR parameters.
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Thiele
authors.initials: T
authors.lastname: Kobus
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Jeroen A W M
authors.initials: JA
authors.lastname: van der Laak
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Marnix C
authors.initials: MC
authors.lastname: Maas
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hambrock
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Caroline C
authors.initials: CC
authors.lastname: Bruggink
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Christina A
authors.initials: CA
authors.lastname: Hulsbergen-van de Kaa
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Tom W J
authors.initials: TW
authors.lastname: Scheenen
authors.affiliation: From the Department of Radiology and Nuclear Medicine (T.K., M.C.M., T.H., C.C.B., T.W.J.S., A.H.) and Department of Pathology (J.A.W.M.v.d.L., C.A.H.v.d.K.), Radboud University Medical Center, Geert Grooteplein 10, 6525 GA Nijmegen, the Netherlands.
authors.forename: Arend
authors.initials: A
authors.lastname: Heerschap
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D002794:Choline / Q000378:metabolism; D019343:Citric Acid / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D013096:Spermine / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D019343:Citric Acid; D013096:Spermine; D003401:Creatine; D002794:Choline