Interestingly, the transition to the severe myeloma phenotype is marked by a striking absence of CLL cells, suggesting competition for growth and/or survival limiting factors such as nutrients [49] or cytokines like BAFF, potentially facilitated through BCMA expression and its shedding [50], a hypothesis that warrants further exploration. This evidence concerns the gene TNFSF13B and B-cell chronic lymphocytic leukemia.