A diagnosis of SLL/CLL is established through correlation of morphology and immunophenotype [6,10], typically showing CD5 and CD23 co-expression with negativity for Cyclin D1 and CD10, while lymphoid enhancer-binding factor 1 (LEF1) positivity further supports the diagnosis [9,10,13]. This evidence concerns the gene CCND1 and B-cell chronic lymphocytic leukemia.