Absence of a common founder mutation in patients with cooccurring myelodysplastic syndrome and plasma cell disorder

Concurrent myelodysplastic malignancies and plasma cell neoplasms; a clinicopathological study with prognostic implications

Plasma cell neoplasms (PCN) have infrequently been reported in patients with myelodysplastic syndrome (MDS) and even more rarely in those with myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN). We report the clinicopathologic features of 26 patients with bone marrow myelodysplasia accompanied by PCN, including 21 patients with MDS and 5 with MDS/MPN. The clinicopathologic features of the MDS/MPN-PCN were compared to those of the MDS-PCN group and 68 cases of MDS/MPN without PCN, respectively. The MDS/MPN-PCN group was notable for increased reticulin fibrosis > grade 1 when compared to both the MDS/MPN (p = 0.007) and MDS-PCN (p = 0.02) groups. MDS/MPN-PCN was associated with worse overall survival when compared with MDS-PCN (p = 0.03) and but not with MDS/MPN. Notably, hemoglobin level <8 g/dl (p = 0.008), and IDH2 somatic mutation (p = 0.003) were independent predictors of poor overall survival in all patients with MDS/MPN. Analysis of larger cohorts is required to confirm these associations and provide an insight into the pathogenesis.

Clonal hematopoiesis and its emerging effects on cellular therapies

The accumulation of somatic mutations in hematopoietic stem cells during aging, leading to clonal expansion, is linked to a higher risk of cardiovascular mortality and hematologic malignancies. Clinically, clonal hematopoiesis is associated with a pro-inflammatory phenotype of hematopoietic cells and their progeny, inflammatory conditions and a poor outcome for patients with hematologic neoplasms and solid tumors. Here, we review the relevance and complications of clonal hematopoiesis for the treatment of hematologic malignancies with cell therapeutic approaches. In autologous and allogeneic hematopoietic stem cell transplantation native hematopoietic and immune effector cells of clonal origin are transferred, which may affect outcome of the procedure. In chimeric antigen receptor modified T-cell therapy, the effectiveness may be altered by preexisting somatic mutations in genetically modified effector cells or by unmodified bystander cells harboring clonal hematopoiesis. Registry studies and carefully designed prospective trials will be required to assess the relative roles of donor- and recipient-derived individual clonal events for autologous and allogeneic cell therapies and to incorporate novel insights into therapeutic strategies.