CD5 and Burkitt lymphoma: Hummel et al devised a computational algorithm called “core-group extension.” Given a predefined core group of expression profiles that satisfied the WHO criteria for Burkitt's lymphoma (a consensus histologic classification of classic or atypical BL, CD20+, BCL6+, CD10+, BCL2−, CD5−, IG-myc+, and Ki-67 score ≥95%), the algorithm identified additional cases that have a similar pattern of gene expression and identified 58 genes that constituted the molecular Burkitt's lymphoma (mBL) signature.