Excess bone marrow B‐cells in patients with multiple myeloma achieving complete remission following autologous stem cell transplantation is a biomarker for improved survival

B-Cell Regeneration Profile and Minimal Residual Disease Status in Bone Marrow of Treated Multiple Myeloma Patients

“…B-cell recovery during therapy has been previously reported as a strong prognostic factor in MM [14][15][16]23,24,[29][30][31] and a unique feature of MM patients who attain longterm disease control [22,25]. Despite this, the kinetics of B-cell depletion and regeneration in BM during the course of therapy have not been investigated in detail in MM.…”

“…From the prognostic point of view, previous studies on transplant-ineligible elderly MM patients suggested an association between high BCP counts in BM and a poor outcome [24]. In contrast, for the same patient population [24] and both transplant-eligible cases [14,16,[29][30][31], as well as in MM patients with long-term disease control [17,22,25], multiple studies point out better recoveries of BM B-cells and nPC have been associated with better outcomes. In line with these later studies, here we found higher numbers of CD19 − nPC in BM of patients who reached sCR/CR vs. non-CR cases, both at the end induction therapy and at day+100 post-ASCT.…”

“…Suppression of B-cell production and differentiation, in association with reduced levels of (normal) non-involved Igs (i.e., immunoparesis), is a hallmark of MM, which inversely correlates with disease stage and patient outcome [12,13], but this might revert back with therapy [14][15][16][17]. Conventional and novel treatment protocols for MM typically comprise sequential pulses of multiple drugs aimed at achieving and maintaining the highest quality of response [18].…”

“…However, such strategies might result in a cumulative immunosuppressive effect with an increased risk for (more pronounced) immunodeficiency and its related clinical complications [19][20][21]. Altogether, this indicates that recovery of immunoparesis after therapy for MM mostly depends on the ability of the (individual) patient hematopoietic system to regenerate the immune system, particularly the B-cell compartment [14,16,17,[22][23][24][25].…”

Natural history and prognostic impact of oligoclonal humoral response in patients with multiple myeloma after autologous stem cell transplantation: long-term results from a single institution

“…21 An increase in polyclonal B cells in the bone marrow has been reported in these patients. 22 On the other hand, in patients in CR after induction therapy, the disappearance of the oligoclonal bands preceded the serological and clinical relapse. 5 This finding was confirmed in the present series in which, in almost all patients, the oligoclonal bands vanished immediately before or at the time of the reappearance of the original myeloma protein, suggesting a clonal competition among malignant plasma cells and polyclonal B lymphocytes.…”