autologous blood and marrow transplantation - Blog Science ...

Harousseau and Attal 227
Table 1. IFM94 study, comparison of one and two autoSCTs (intention to treat analysis)
Arm A, one autoSCT Arm B, two autoSCTs P value
n 105 95
CR 33% 34% NS
VGPR 7% 11% NS
2-year EFS 52% 58% NS
2-year survival 73% 69% NS
GM-CSF) after transplant and of peripheral blood instead of bone marrow
progenitors has dramatically reduced the duration of myelosuppression induced by
HDT. As a consequence, the duration of hospitalization and, it is hoped, the costs
have been significantly reduced. However, contamination of the autologous graft
by the malignant clone remains a critical concern even with blood progenitors.
Sensitive methods, including amplification of the patient's rearranged gene, allow
myeloma cells to be detected in blood and apheresis products. Attempts to purge
marrow with cyclophosphamide derivatives or monoclonal antibodies are feasible
but induce prolonged myelosuppression. Selection of CD34 +
progenitors appears to
be a promising alternative. Tumor depletion up to 4.5 logs can be obtained with this
technique, but sophisticated assays for detection of minimal residual disease show
the persistence of myeloma cells in the CD34 +
cell fraction. The clinical impact of
this cumbersome and expensive procedure has not yet been fully evaluated. 2
The question of the source of stem cells has been also addressed by the IFM94
trial. At the time of stem cell collection, patients were randomized between
autoBMT and PBPCT. PBPC were collected after priming with G-CSF alone (10
ug/kg/d for 7 days starting on day 17 after VAD course). However, investigators
were allowed to perform a CD34 +
cell selection either on bone marrow or PBPC.
Of the first 200 patients, 172 underwent the second randomization (78 BM, 94
PBPC).
However, 20 patients have not been transplanted (10 ABMT, 10 PBSCT), 22
patients assigned to receive ABMT were actually transplanted with PBPC, and one
patient randomized to receive PBPC was actually transplanted with BM.
According to the protocol, CD34 selection was performed in 35 cases (nine
ABMT, 26 PBPCT). Finally, 129 of the 172 randomized patients (75%) were
transplanted as per protocol (37 BM, 35 CD34, and 57 PBPC). There was no
significant difference between the three groups regarding the main initial characteristics,
the first randomization, and the response to initial CC. With a short
follow-up (median 26 months) the clinical outcome did not appear to differ significantly
(Table 2).
The only difference between the three groups concerned hematopoietic
reconstitution. The median durations of neutropenia (