A total of 185 articles were eventually excluded for reasons as the following: 1) the article did not involve the evaluation of the relationship between Ki-67 expression and 18F-FDG uptake (n = 134); 2) the number of cases studied was fewer than 10 (n = 17); 3) the original data in the article failed to generate the correlation coefficient values (n = 27); 4) part of the data in the study appeared in other articles (n = 6); and 5) most of the cases studied were benign tumors (n = 1). Here, MKI67 is linked to benign neoplasm.