Background: The unfavorable outcome of acute myelogenous leukemia(AML) at higher age is due both to biological features of the disease, which are known to be related to inherent drug resistance, and to poor tolerance to standard-dose chemotherapy.
For these reasons, severe infections due to yelosuppression were responsible for most of the early fatal complications during chemotherapy. Thus, reducing the phase of critical myelosuppression using hematopoietic growth factors(HGFs) would allow effective antileukernic chemotherapy.
Methods: From January 1990 to December 1994, 24 patients over the age of 60 years with newly diagnosed AN[L who underwent remission induction chemotherapy were entered in this study. We have analyzed the effect of HGFs[granulocyte
colony-stimulating factor(G-CSF) or granulocyte-macrophage colony-stimulating factor(GM-CSF)] and therapeutic outcomes.
Results :
1) Twenty-four patients entered the study and 9 of them received HGFs started on day 11 after chemotherapy, The two groups were well balanced for all initial characteristics.
2) The recovery time of neutrophils to 500/μL after chemotherapy was 24±9 in the patients who received HGFs and 43±21 days in the controls(P=0.02). And the recovery
time of platelets to 50,000/μL was significantly shorter in the patients who received HGFs than in the controls(26±11 vs 40±19, p=0.04). Infectious complications were less
frequent and less severe in the group received with HGFs(66.7% vs 100%, f=0.02).
There was no evidence that HGFs accelerated the regrowth of leukemic cells.
3) The use of HGFs had not substantial effect on the complete remission(CR)(55.6% vs 53.3%). Th% frequency of deaths during bone marrow hypoplasia was lower in
patients who received with HGFs than in the controls(0% vs 26.7%, p=0.04).
4) The rate of relapse was not different in the two groups, and survival analysis after a median follow-up of 366 days revealed no significant influence of the use of HGFs on
CR duration and overall survival.
Conclusion : These Results suggested that HGFs were safe in elderly patients with AML after induction chemotherapy, accelerating neutrophil recovery and thereby reducing
the incidence of documented infection without affecting the regrowth of leukemic cells.
Further evaluations about more intensive chemotherapy and supportive cares involving the use of HGFs may be warranted.