Whether the differences between morphologically typical and atypical cases in terms of IgVH mutational status and CD38 and CD20 expression might be an expression of a somehow different disease in terms of cell-of-origin unmutated IgVH cases more observed in atypical CLL could be the expression of the development of a different cell needs to be addressed by specific studies. Here, MS4A1 is linked to B-cell chronic lymphocytic leukemia.