title: [Value of diffusion-weighted MRI in differentiation between benign and malignant polypoid gallbladder lesions].
abstract: OBJECTIVE
  To evaluate the efficiency of diffusion-weighted MRI in differentiating between benign and malignant polypoid gallbladder lesions.
  
  
  METHODS
  The study population consisted of 10 benign (5 polyps, 3 adenomyomatosis and 2 adenomas) and 13 malignant (all adenocarcinomas) polypoid gallbladder lesions treated in hospital from November 2007 to May 2014. DWI was evaluated by two observers. Qualitatively, the signal intensity of the lesions on DWI was visually evaluated and categorized as iso, high, or very high signal.Quantitatively, the ADC values of the lesions were measured from ADC maps. Statistical analysis was performed using a two-tailed Fisher's exact test and the Mann-Whitney test, respectively. The cut-off values were determined by receiver operating characteristic analysis.
  
  
  RESULTS
  Qualitative analysis revealed a statistical difference (P=0.036). In the 10 benign lesions, three were categorized as iso, 5 as high, and 2 as very high signal.Four of the 13 malignant lesions were categorized as high, and the remaining 9 were categorized as very high signal. The mean ADC value of the malignant lesions [(1.13±0.28)×10(-3) mm2/s] was significantly lower than that of benign lesions [(2.22±0.42)×10(-3) mm2/s, P<0.01]. The cut-off value between cancer and the benign lesions was 1.5×10(-3) mm2/s, the sensitivity, specificity, and accuracy were 92%, 100% and 96%, respectively.
  
  
  CONCLUSIONS
  Diffusion-weighted MRI may be useful in differentiating between benign and malignant polypoid gallbladder lesions.
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China; Email: yijiang_hu@aliyun.com.
authors.forename: Yijiang
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Di
authors.initials: D
authors.lastname: Jia
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Zhengdao
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Wang
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Huifang
authors.initials: H
authors.lastname: Cai
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yang
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Zhaoping
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Tonghua
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Imaging Department, Zhangjiagang First People's Hospital, Suzhou 215600, China.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Chen
mesh_terms: D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D005704:Gallbladder; D005705:Gallbladder Diseases; D006801:Humans; D012372:ROC Curve