Clinical Investigation of G-CSF-Priming Regimen in Treatment of Relapsing, Refractory and Senile Acute Myeloid Leukemia.

Objective:To evaluate the clinical outcome of granulocyte colony-stimulating factor (G-CSF) priming regimen in treatment of refractory, relapsing and senile aute myeloid leukemia.

Materials and Methods:16 patients, 10 men and 6 women ranged in age from 15 to 78 years (median 48), with refractory, relapsing or senile acute myeloid leukemia were treated in our hospital between March 2002 and January 2004. All patients were diagnosed with MIC (morphologic, immunologic, cytogenetic) classification. The control group consists of 18 patients (12 men and 6 women, median age 48) with refractory, relapsing or senile acute myeloid leukemia treated in our hospital between 1999 and 2002. All of them were also diagnosed with MIC. All patients enrolled were treated with G-CSF-priming regimen consisting of low-dose cytosine arabinoside (Ara-C 10mg.m⁻².12h⁻¹, subcutaneously,day1–14), aclarubicin (Acla5-7mg.m⁻².d⁻¹, continuous intravenous infusion, day 1–8; or 10–14mg.m⁻².d⁻¹, continuous intravenous infusion, day1–4) or homoharringtonine (HHT 1mg.m⁻².d⁻¹, continuous intravenous infusion, day1–14), and concurrent use of G-CSF (100ug.m⁻².12h⁻¹, subcutaneously, day 1–14). In the course of chemotherapy, blood routine examinations were made every other day, and G-CSF was suspended while WBC>20x10⁹/L. Chemotherapy intermission was 14–21 days. If two courses were of no effect, then the investigation was terminated. Patients in the control group received intensive chemotherapy with medium /high dosed Ara-C (1-3g.m⁻².12h⁻¹× 3–5d), combined with mitoxantrone or daunorubicin (DNR) or etoposide (vp-16).Statistics:Enumeration data was analyzed by Chi-square test.

Results: All patients accomplished the chemotherapy, with no treatment related death. 9 of the 16 patients achieved complete remission. The CR rate was 56.25%, compared with 22.2% of the control group (Χ²=4.15, P<0.05). However, the total effective rate (68.75%) was not statistically higher than the control group (44.4%) (Χ²=2.03, P>0.05). Therapy related mortality (0.0%) was apparently decreased in priming group than in control group (38.9%) (Χ²=7.84, P<0.01).

Conclusions:Our study shows that the priming regimen is effective and safe to refractory, relapsing, secondary or senile acute myeloid leukemia. Further studies are necessary to evaluate the long-term effects of this new therapeutic regimen in AML.