title: Diagnosed chest lesion on diffusion-weighted magnetic resonance images using apparent diffusion coefficients.
abstract: OBJECTIVE
  A novel diagnostic method using the standard deviation (SD) value of apparent diffusion coefficient (ADC) by diffusion-weighted (DWI) magnetic resonance imaging (MRI) is applied for differential diagnosis of primary chest cancers, metastatic tumors and benign tumors.
  
  
  METHODS
  This retrospective study enrolled 27 patients (20 males, 7 female; age, 15-85; mean age, 68) who had thoracic mass lesions in the last three years and underwent an MRI chest examination at our institution. In total, 29 mass lesions were analyzed using SD of ADC and DWI. Lesions were divided into five groups: Primary lung cancers (N = 10); esophageal cancers (N = 5); metastatic tumors (N = 8); benign tumors (N = 3); and inflammatory lesions (N = 3). Quantitative assessment of MRI parameters of mass lesions was performed. The ADC value was acquired based on the average of the entire tumor area. The error-plot, t-test and the area under receiver operating characteristic (AUC) were applied for statistical analysis.
  
  
  RESULTS
  The SD of ADC value (mean±SD) was (4.867±1.359)×10-4 mm2/sec in primary lung cancers, and (3.598±0.350)×10-4 mm2/sec in metastatic tumors. The SD of ADC values of primary lung cancers and metastatic tumors (P <  0.05) were significantly different and the AUC was 0.800 (P <  0.05). The means of SD of ADC values was 4.532±1.406×10-4 mm2/sec and 2.973±0.364×10-4 mm2/sec for malignant tumors (including primary lung cancers, esophageal cancers) and benign tumors with respectively. The mean of SD of ADC values between malignant chest tumors and benign chest tumors was shown significant difference (P <  0.01). The values of AUC was 0.967 between malignant chest tumors and benign chest tumors (P <  0.05). The ADC values for primary lung cancers, metastatic tumors and benign tumors were not significantly difference (P >  0.05).
  
  
  CONCLUSIONS
  The mean of SD of ADC value by DWI can be used for differential diagnosis of chest lesions.
authors.affiliation: Department of Radiology, E-DA Hospital, I-Shou University, Kaohsiung City, Taiwan.|Department of Medical Imaging and Radiological Sciences, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Nan-Han
authors.initials: NH
authors.lastname: Lu
authors.affiliation: Department of General Sugary, E-DA Hospital, I-Shou University, Kaohsiung City, Taiwan.|The School of Medicine, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Chao-Ming
authors.initials: CM
authors.lastname: Hung
authors.affiliation: Department of Radiology, E-DA Hospital, I-Shou University, Kaohsiung City, Taiwan.|Department of Medical Imaging and Radiological Sciences, I-Shou University, Kaohsiung City, Taiwan.|Department of Information Engineering, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Kuo-Ying
authors.initials: KY
authors.lastname: Liu
authors.affiliation: Department of Medical Imaging and Radiological Sciences, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Tai-Been
authors.initials: TB
authors.lastname: Chen
authors.affiliation: Department of Medical Imaging and Radiological Sciences, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Yung-Hui
authors.initials: YH
authors.lastname: Huang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
keywords: AUC; Diffusion-weighted imaging; SD of ADC