Daratumumab-based induction and autologous transplantation in concomitant multiple myeloma and chronic myeloid leukemia.

The coexistence of chronic myeloid leukemia (CML) and multiple myeloma (MM) is a rare clinical condition. By means of FISH and molecular analysis on both sorted CD138 plasma cells and cryopreserved CD34 stem cells, a distinct clonal origin of the hematological malignancies was demonstrated in our case. We report on the first patient diagnosed with CML and MM treated with daratumumab, bortezomib, thalidomide, and dexamethasone (Dara-VTd) induction, stem-cell collection, and autologous stem cell transplantation (ASCT). The co-administration of Dara-VTd and imatinib proved feasible and highly effective in the management of both CML and MM. Despite concerns with stem cell mobilization and collection in patients exposed to daratumumab, in our experience the use of higher cyclophosphamide dose 4 g/m2 together with plerixafor granted optimal stem cell mobilization and collection, irrespective of daratumumab, concomitant myeloid neoplasm, and imatinib. Moreover, ASCT was easily performed with a rapid hematological reconstitution.