A systematic meta-analysis including 12 studies of immunohistochemical staining for Ki-67 in DLBCL showed that the range of thresholds for the high expression of this marker, chosen by the authors, ranges from 20 to 85%, and Ki-67 overexpression is associated with high invasiveness, rapid disease progression and poor prognosis [26]. This evidence concerns the gene MKI67 and diffuse large B-cell lymphoma.