BCR and B-cell chronic lymphocytic leukemia: Other than the conventional EV markers, several CLL-specific surface markers have been identified; these include components of the BCR pathway (such as IgM, CD19, and Lyn) and other molecules (such as HLA-DR, CD82, CD37, CD54, CD20, CD5, and CD52) [41,42,44,45,46,47,48,49] (Figure 1).