Among SWM patients, the 2/8 discrepant cases were due to the lack of cPC and cB-lymphocytes as detected by NGF in one case, and the coexistence of IgM cPC with a typical MM-like phenotype and an unrelated CLL-like MBL cB-cell population suggesting independent disorders. The gene discussed is CD40LG; the disease is B-cell chronic lymphocytic leukemia.