Rundgren IM, et al. - Researchers analyzed a consecutive group of myeloma patients who had received the presently used induction therapy, to evaluate total monocyte and monocyte subset (classical, intermediate and non-classical monocytes) peripheral blood levels prior to and after auto-transplantation for these patients, by using flow cytometry. Early post-auto-transplantation, the normalization of the total level of circulating monocytes was seen, but considerable variation in pre- and post-transplant levels of many monocyte subsets was also detected between patients. A non-random influence of melphalan on monocyte subsets was revealed. For those managed with induction therapy including immunomodulatory drugs, a stronger influence of melphalan on total and classical monocyte levels was evident. The period of pancytopenia was accompanied by a reduction in total monocytes and monocyte subset levels, but the occurrence of monocyte reconstitution prior to hematopoietic reconstitution was reported.