According to modern concepts based on results of examination of the gene expression profile, there are several subtypes of diffuse large B cell lymphoma (DLBCL): germinal center B cell-like (GCB) and activated B cell-like (ABC) lymphomas. Genes c-MYC, BCL6, and BCL2 are key regulators of B-cell germinal (follicular) differentiation. Genetic abnormalities with their participation are most common in molecular pathogenesis of DLBCL. A total level of activity as well as mechanisms that lead to overexpression each of these genes and production of corresponding proteins have an impact on a disease prognosis. We assume that quantitative assay of c-MYC, BCL6, and BCL2 gene expression, as well as proteins encoded by these genes, can allow to determine high risk DLBCL patients with great accuracy.