Primary therapy with 140 mg/m2 melphalan without rescue results in high response rates in myeloma with very long-term survival in some patients (Powles et al. Blood 1997; 90 Suppl l:356a). This study was designed to see if enough stem cells (1 x 10' CD34+ cells/kg) could be harvested at presentation to perform an autograft as primary therapy. Patients received 1 g/mVd methylprednisolone (MP) (d 1-6) and 12-16 ng/kg/d G-CSF (d 3-6), and were apheresed (2x blood volume) on d 6-7. 20 patients (13 M, 7 F; 34-67 y, median 56; 13 IgG, 4 IgA, 2 light chain, 1 non-secretory) were enrolled from 10/99 to 6/00. 1 patient could not be harvested because of progressive renal failure requiring dialysis. 0.37-5.63 x 106 CD34+ cells/kg (median 1.36) were harvested from the remaining 19. The yield was <1 × 106 CD34+ cells/kg in 4 (21%). 10 of these patients were harvested again after C-VAMP (cyclophosphamide, vincristine, doxorubicin, and MP) induction chemotherapy using a similar mobilization-collection protocol (G-CSF; no MP). The CD34 yields, 0.93-5.83 × 106/kg (median 2.53), were significantly higher (P=0.007) than the previous yields for the same 10 patients, and each patient's post-chemotherapy collection was higher than the initial one. These data were compared to 82 historic controls who were harvested in an identical fashion (G-CSF; no MP) after initial induction with C-VAMP (0.04-19.97 × 106 CD34+ cells/kg, median 2.74). The control patients had significantly (P=0.01 ) higher cell yields than the 19 study patients at presentation. However, the control cell yields were comparable to the post-C-VAMP cell yields in the 10 study patients (P=0.7). The proportion of control patients with <1 × 106 CD34+ cells/kg (11%, n=9) was not significantly different (P=0.3) from the study group. Enough cells for two transplants (second as backup) (2 × 106CD34+ cells/kg) could be collected in only 3 of 19 patients compared with 53 of 82 control patients (P<0.0001). The plasma cell content of the 19 collections was 0.1-64.7 × 106 CD38/138+ cells/kg (median 0.49). However, plasma cell contamination of the harvest has not been shown to increase relapse after autografting. We conclude that while it is possible to harvest enough stem cells for 1 autograft at the time of diagnosis in 75% of myeloma patients. These collections are inferior to those performed after induction chemotherapy but are sufficient to explore the possibility of upfront autografts for the majority of patients as a new treatment strategy.
|Original language||English (US)|
|Issue number||11 PART I|
|State||Published - 2000|
ASJC Scopus subject areas
- Cell Biology