Mutations involving STAT6 (VAF 5.4%), TNFRSF14 (VAF 5.4%), CREBBP (VAF 8.1%), CREBBP (VAF 6.2%), and FOXO1 start-loss were supportive of the diagnosis of CD23+dFL, while detection of trisomy 12 by FISH was supportive of the diagnosis of CLL/SLL. This evidence concerns the gene STAT6 and B-cell chronic lymphocytic leukemia.