Luo ZW, et al. - From January 1970 to July 2017, authors estimated the electronic databases, including EMBASE, PubMed, Cochrane Library and Web of Knowledge database to analyze the prognostic value of Ki-67 expression in subjects with colorectal cancer. They observed pooled hazard ratios of 1.54 for overall survival and 1.43 for disease-free survival in the univariate analysis. They indicated it, a valuable predictive method for poor prognosis of colorectal cancer as high Ki-67 expression was significantly associated with poor overall survival and disease-free survival.