According to a study published recently in Blood Cancer Journal, clonal plasma cells (CPC) present in the donor graft are predictive of worse overall survival (OS) after autologous hematopoietic stem cell transplantation (AHSCT) in patients with multiple myeloma (MM).
MM is an incurable cancer of the plasma cells. First-line treatment involves a combination of proteasome inhibitors and immunomodulatory drugs, which often produce favorable 5-year OS outcomes with manageable toxicity profiles. For patients who do not respond to first-line treatment, stem-cell transplant is an option.
Transplanted marrow can come from another individual (allogeneic) or, occasionally, from the recipient themselves (autologous). In AHSCT, healthy marrow is stored and given back to the patient later. Many patients who receive AHSCT eventually relapse, and researchers at the MD Anderson Cancer Center believe the reason is residual CPCs in the autograft.
Oren Pasvolsky, MD, and coauthors conducted a retrospective review of their institutional database to determine whether there was any correlation between the presence of CPCs in the autograft and survival outcomes.
Using next-generation flow cytometry (NGF), the researchers identified 75 autografts with residual CPCs and 341 with no residual CPCs at their institution between 2008 and 2018. With this sample, they were able to determine that “The CPC + group was less likely to achieve [minimal residual disease (MRD)]-negative complete remission post-transplant (11% vs. 42%; p < 0.001).”
The study reported progression-free survival (PFS) and OS outcomes for both the CPC+ and CPC- groups. The CPC- group had a median PFS of 32.1 months versus only 12.8 months in the CPC+ group. Similarly, the CPC- group had an OS of 81.2 months, significantly greater than the 36.4-month OS in the CPC+ group (P<.001).
These results led the authors to conclude that “the current study shows a major impact of CPC in the autograft on post-autoHCT outcomes in HRMM.” The authors suggest that “Novel strategies for purging of CPC could improve patient outcomes.”
This article was originally published on bloodcancerstoday.com.