title: Apparent diffusion coefficient measurement by diffusion weighted magnetic resonance imaging is a useful tool in differentiating renal tumors.
abstract: BACKGROUND
  To determine the clinical value of apparent diffusion coefficient (ADC) measurement by diffusion weighted magnetic resonance imaging (DW-MRI) in differentiating renal tumors.
  
  
  METHODS
  Electronic databases were searched using combinations of keywords and free words relating to renal tumor, ADC and DW-MRI. Based on carefully selected inclusion and exclusion criteria, relevant case-control studies were identified and the related clinical data was acquired. Statistical analyses were performed using STATA 12.0 (Stata Corporation, College station, TX).
  
  
  RESULTS
  Sixteen case-control studies were ultimately included in the present meta-analysis. These 16 high quality studies contained a combined total of 438 normal renal tissues and 832 renal tumor lesions (597 malignant and 235 benign). The results revealed that ADC values of malignant renal tumor tissues were markedly lower than normal renal tissues and benign renal tumor tissues. ADC values of benign renal tumor tissues were also significantly lower than normal renal tissue.
  
  
  CONCLUSIONS
  ADC measurement by DW-MRI provided clinically useful information on the internal structure of renal tumors and could be an important radiographic index for differentiation of malignant renal tumors from benign renal tumors.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Dalian Medical University, Zhongshan Road No. 222, Xigang District, Dalian, 116011, P. R China. liujinghong704@126.com.
authors.forename: Jing-Hong
authors.initials: JH
authors.lastname: Liu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Dalian Medical University, Zhongshan Road No. 222, Xigang District, Dalian, 116011, P. R China. tianshifeng704@126.com.
authors.forename: Shi-Feng
authors.initials: SF
authors.lastname: Tian
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Dalian Medical University, Zhongshan Road No. 222, Xigang District, Dalian, 116011, P. R China. juye704@126.com.
authors.forename: Ye
authors.initials: Y
authors.lastname: Ju
authors.affiliation: Department of Radiology, Dalian Medical University, Dalian, 116044, P. R China. liye704@126.com.
authors.forename: Ye
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Radiology, Dalian Medical University, Dalian, 116044, P. R China. chenanliang704@126.com.
authors.forename: An-Liang
authors.initials: AL
authors.lastname: Chen
authors.affiliation: Department of Radiology, Dalian Medical University, Dalian, 116044, P. R China. chenlihua704@126.com.
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Chen
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Dalian Medical University, Zhongshan Road No. 222, Xigang District, Dalian, 116011, P. R China. liuailian704@126.com.
authors.forename: Ai-Lian
authors.initials: AL
authors.lastname: Liu
mesh_terms: D016022:Case-Control Studies; D016208:Databases, Factual; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis*; D017594:Publication Bias; D012680:Sensitivity and Specificity