title: Ki-67 labeling index can be used as a prognostic marker in gastrointestinal stromal tumor: a systematic review and meta-analysis.
abstract: OBJECTIVE
  The aim of this study was to investigate the prognostic relevance of the Ki-67 labeling index (LI) in gastrointestinal stromal tumor (GIST) through a systematic review, meta-analysis and diagnostic test accuracy review.
  
  
  METHODS
  The study included 1,967 GIST cases from 24 eligible studies. We investigated the correlation between high Ki-67 LI and survival and the proper criteria for high Ki-67 LI. In addition, a diagnostic test accuracy review was conducted to evaluate the predictive role of high Ki-67 LI for higher risk of tumor recurrence.
  
  
  RESULTS
  A high Ki-67 LI was significantly correlated with worse disease-free survival (DFS) (hazard ratio [HR] 3.658, 95% confidence interval [CI] 2.687-4.979, p&lt;0.001) and overall survival (OS) (HR 3.730, 95% CI 2.819-4.936, p&lt;0.001). With regard to DFS and OS, the subgroup with a cutoff value of &gt;4% for high Ki-67 LI had a higher HR than the subgroup with a ≤4% cutoff. In the diagnostic test accuracy review, a high Ki-67 LI was significantly correlated with higher risk of tumor recurrence (pooled sensitivity = 0.44, pooled specificity = 0.87, area under the curve on the summary receiver operating characteristic curve = 0.656).
  
  
  CONCLUSIONS
  Our results showed that a high Ki-67 LI was significantly correlated with worse prognosis and higher risk of tumor recurrence in GIST. Further prospective studies of the prognostic role of Ki-67 LI are necessary prior to application in clinical practice.
authors.affiliation: Department of Pathology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul - South Korea.
authors.forename: Jung-Soo
authors.initials: JS
authors.lastname: Pyo
authors.affiliation: Department of Pathology, Inje University Sanggye Paik Hospital, Seoul - South Korea.
authors.forename: Guhyun
authors.initials: G
authors.lastname: Kang
authors.affiliation: Department of Pathology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul - South Korea.
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Sohn
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D005770:Gastrointestinal Neoplasms / Q000235:genetics / Q000378:metabolism*; D046152:Gastrointestinal Stromal Tumors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D019394:Ki-67 Antigen / Q000235:genetics / Q000378:metabolism*; D011379:Prognosis; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen