Stem cell mobilization in multiple myeloma patients: Do we need an age‐adjusted regimen for the elderly?

Abstract

The upper age limit for autologous progenitor cell transplantation in multiple myeloma patients is increasing continuously. We examined whether this shift in the age of pretreated myeloma patients requires modification of mobilization regimen. We compared retrospectively 21 consecutive progenitor cell mobilizations in 15 pts < 60 years (median age 56, range 37-59) with 33 consecutive mobilizations in 23 pts > 60 years (median age 65, range 60-73) of age. The number of CD34 positive circulating cells before scheduled leukapheresis was a mean of 67,935 cells/mL (SEM +/- 17,614) in the younger population and a mean of 19,069 (SEM +/- 5,396) for older pts (P = 0.0027). In patients >60 years, 13/33 mobilizations (including 2 patients with 2 failing attempts) were not successful (39%), compared to 6/21 mobilizations (29%, including 1 patient with 3 failing attempts) in the younger population. The increased number of progenitor cells in the grafts of younger patients led to a more rapid regeneration of leukocytes and platelets after stem cell infusion. Our data show that stem cell mobilization in older multiple myeloma patients is inferior compared to a younger patient population. There is a trend towards more leukapheresis until the target stem cell dose has been collected, and the decreased number of progenitor cells in the actual graft delays engraftment of leukocytes and platelets. The overall number of unsuccessful mobilization attempts, however, did not differ significantly between both age groups. A special "age-adjusted" increase in the dose of growth factors seems unjustified. Improvements in timing of leukapheresis, growth factor application, and mobilizing chemotherapy regimen as well as the use of alternative cytokines should be investigated for both age groups.

Plerixafor in patients with lymphoma and multiple myeloma: effectiveness in cases with very low circulating CD34+ cell levels and preemptive intervention vs remobilization

“…[7][8][9][10][11][12][13][14][15][16] However, the value of patient characteristics and prior treatment clinical factors to successfully score and accurately predict the risk of poor mobilization is controversial, and recent studies do suggest that they are inaccurate predictors and should not be used to identify candidates for optimized strategies to prevent mobilization failure. 17,18 At present, the measurement of preapheresis levels of CD34+ cells in PB 7,[19][20][21][22] is the most robust and recommended indicator to identify potential poor mobilizers and efficiently rescue them with novel mobilization strategies, including the use of plerixafor.…”

A plerixafor-based strategy allows adequate hematopoietic stem cell collection in poor mobilizers: results from the Canadian Special Access Program

“…Primary mobilization failure occurs in 5-40% of patients. [5][6][7][8][9] Risk factors for poor mobilization include older age, 10 prior radiation therapy, extensive prior chemotherapy, exposure to lenalidomide or purine analogues and extensive BM involvement by malignancy. [11][12][13] Options for those patients who fail to mobilize are limited.…”

Peripheral blood stem cell collection in elderly patients

“…One of the factors directly affecting the feasibility of these procedures is the mobilization capacity of CD34+ cells. The available data are contradictory because several studies have demonstrated that mobilization capacity is poorer in elderly patients compared with younger patients [15][16][17][18][19]. Of our 359 patients, the success of the mobilization procedure was similar between younger and older patients: 90.6% versus 92%, respectively.…”