title: Differential diagnosis of benign and malignant breast masses using diffusion-weighted magnetic resonance imaging.
abstract: BACKGROUND
  Diffusion-weighted magnetic resonance imaging (DW-MRI) is different from conventional diagnostic methods and has the potential to delineate the microscopic anatomy of a target tissue or organ. The purpose of our study was to evaluate the value of DW-MRI in the diagnosis of benign and malignant breast masses, which would help the clinical surgeon to decide the scope and pattern of operation.
  
  
  METHODS
  A total of 52 female patients with palpable solid breast masses received breast MRI scans using routine sequences, dynamic contrast-enhanced imaging, and diffusion-weighted echo-planar imaging at b values of 400, 600, and 800 s/mm(2), respectively. Two regions of interest (ROIs) were plotted, with a smaller ROI for the highest signal and a larger ROI for the overall lesion. Apparent diffusion coefficient (ADC) values were calculated at three different b values for all detectable lesions and from two different ROIs. The sensitivity, specificity, positive predictive value, and positive likelihood ratio of DW-MRI were determined for comparison with histological results.
  
  
  RESULTS
  A total of 49 (49/52, 94.2%) lesions were detected using DW-MRI, including 20 benign lesions (two lesions detected in the same patient) and 29 malignant lesions. Benign lesion had a higher mean ADC value than their malignant counterparts, regardless of b value. According to the receiver operating characteristic (ROC) curve, the smaller-range ROI was more effective in differentiation between benign and malignant lesions. The area under the ROC curve was the largest at a b value of 800 s/mm(2). With a threshold ADC value at 1.23 × 10(-3) mm(2)/s, DW-MRI achieved a sensitivity of 82.8%, specificity of 90.0%, positive predictive value of 92.3%, and positive likelihood ratio of 8.3 for differentiating benign and malignant lesions.
  
  
  CONCLUSIONS
  DW-MRI is an accurate diagnostic tool for differentiation between benign and malignant breast lesions, with an optimal b value of 800 s/mm(2). A smaller-range ROI focusing on the highest signal has a better differential value.
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. qinghuamin1@163.com.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Min
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. kangwei_shao@163.com.
authors.forename: Kangwei
authors.initials: K
authors.lastname: Shao
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. lulanzhai22@163.com.
authors.forename: Lulan
authors.initials: L
authors.lastname: Zhai
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. weiludr@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. caisongzhuu@163.com.
authors.forename: Caisong
authors.initials: C
authors.lastname: Zhu
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. lixin_yuan1@163.com.
authors.forename: Lixin
authors.initials: L
authors.lastname: Yuan
authors.affiliation: Department of Radiology, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Changning District, Shanghai, 200336, PR China. jun_yangjy@163.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000175:diagnosis*; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis*; D018275:Carcinoma, Lobular / Q000175:diagnosis*; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D055815:Young Adult