Expression of c-Myc and p53 correlates with clinical outcome in diffuse large B-cell lymphomas

We performed a retrospective immunohistochemical study of the relationships between clinical manifestations and outcomes of diffuse large B-cell lymphoma (DLBCL) and expression of oncogenic proteins in 21 cases of DLBCL at various clinical stages. Cases of nodal origin expressed p53 more often and presented with high clinical stage more frequently than those of extranodal origin. Expression of c-Myc or p53, but not Bcl-6, Bcl-2, or Bcl-1, showed a statistically significant positive correlation with high clinical stage at presentation and with high or high-intermediate risk. Coexpression of c-Myc and p53 occurred in 7 of 12 patients with high clinical stage bur was absent in patients with low clinical stage; coexpression was more frequent in patients with high or high-intermediate risk than in patients with low or low-intermediate risk. Four patients with this coexppression pattern demonstrated all unusually aggressive clinical course (median survival, 7 months). Coexpression of c-Myc and p53 seems to be a better indicator than the MIBI proliferative index for identification of a cohort of aggressive disease in patients with DLBCL.