Considering the expression of bcl-6, CD10 and MUM1 as well as CD44, CD138, bcl-2 and other biomarkers, different algorithms to identify GC and non-CG DLBCL have been proposed (e.g. Barrans et al. 2002b; Colomo et al. 2003; Tzankov et al. 2003a; Chang et al. 2004; Hans et al. 2004; Zinzani et al. 2005, Tzankov et al. 2006; Muris et al. 2006b; Oh et al. 2006; van Imhoff et al. 2006), but confirming the relevance of most of them is hampered by failures in results reproducibility and low validity. The gene discussed is IRF4; the disease is diffuse large B-cell lymphoma.