The Ki-67 labeling index, a commonly used marker of proliferation in oncology, is typically determined by counting cells that are positively stained out of the total number of cells [5]. While DLBCL frequently has a Ki-67 index ranging from 40% to 90%, BL has a proliferation index of nearly 100% [4,6]. This evidence concerns the gene MKI67 and diffuse large B-cell lymphoma.