title: Role of magnetic resonance spectroscopy for the differentiation of recurrent glioma from radiation necrosis: a systematic review and meta-analysis.
abstract: OBJECTIVE
  Differentiating glioma recurrence from radiation necrosis remains a great challenge. We conducted a meta-analysis to evaluate the diagnostic quality of magnetic resonance spectroscopy (MRS) in differentiating glioma recurrence from radiation necrosis.
  
  
  METHODS
  Studies about evaluation of MRS for the differential diagnosis of glioma recurrence from radiation necrosis were systematically searched in PubMed, Embase and Chinese Biomedical databases up to May 4, 2014. The data were extracted to perform heterogeneity test, threshold effect test and to calculate sensitivity (SEN), specificity (SPE) and areas under summary receiver operating characteristic curve (SROC).
  
  
  RESULTS
  Eighteen articles comprising a total sample size of 455 patients (447 lesions) with suspected glioma recurrence after radiotherapy, met all inclusion and exclusion criteria, and were included in our meta-analysis. Quantitative synthesis of studies showed that the pooled SEN and SPE for Cho/Cr ratio were 0.83 (95% CI: 0.77, 0.89) and 0.83 (95% CI: 0.74, 0.90). The area under the curve (AUC) under the SROC was 0.9001. The pooled SEN and SPE for Cho/NAA ratio were 0.88 (95% CI: 0.81, 0.93) and 0.86 (95% CI: 0.76, 0.93). The AUC under the SROC was 0.9185.
  
  
  CONCLUSIONS
  This meta-analysis shows that MRS alone has moderate diagnostic performance in differentiating glioma recurrence from radiation necrosis using metabolite ratios like Cho/Cr and Cho/NAA ratio. It is strongly recommended that MRS should combine other advanced imaging technologies to improve diagnostic accuracy. This article underlines the importance of implementing multimodal imaging trials and multicentre trials in the future.
authors.affiliation: Department of Neurosurgery, Air Force General Hospital of the Chinese PLA, 30 Fucheng Road, Haidian District, Beijing 100142, China; Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road,Haidian District, Beijing 100853, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Anesthesiology, Beijing Military General Hospital, Beijing 100700, China.
authors.forename: Li
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road,Haidian District, Beijing 100853, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road,Haidian District, Beijing 100853, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road,Haidian District, Beijing 100853, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Wu
authors.affiliation: Department of Neurosurgery, Chinese PLA General Hospital, 28 Fuxing Road,Haidian District, Beijing 100853, China. Electronic address: bn_xu@yahoo.com.
authors.forename: Bai-Nan
authors.initials: BN
authors.lastname: Xu
mesh_terms: D001927:Brain Diseases / Q000175:diagnosis / Q000473:pathology; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005910:Glioma / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009336:Necrosis; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000473:pathology; D011832:Radiation Injuries / Q000175:diagnosis* / Q000473:pathology