IRF2 and B-cell chronic lymphocytic leukemia: Finally, we observed a different distribution of CLL-IPI risk groups (low, intermediate, high, very high) in IRF2-3low and IRF2-3high patients, with a significantly higher frequency of patients with low CLL-IPI risk scores in the IRF2-3low vs. the IRF2-3high group (p < 0.001, Fisher exact test).