Introduction

Allogeneic hematopoietic stem cell transplantation (HSCT) is currently the only curative therapy for myelodysplastic syndrome (MDS). However, the reported disease-free survival rates of patients undergoing allogeneic HSCT for MDS remains low, ranging between 24 and 56%.^{1, 2, 3, 4, 5, 6, 7, 8} The most important cause of treatment failure is disease recurrence, which is reported to range between 23 and 48.^{1, 2, 3, 4, 5, 6, 7, 8} As granulocyte colony-stimulating factor (G-CSF) has been shown to increase the susceptibility of some myeloid leukemia cells to cytarabine in vitro,^{9, 10, 11} it has been used clinically in combination with cytarabine for refractory acute myelogenous leukemia (AML) or MDS.^{12, 13, 14, 15} In our previous report, G-CSF was administered simultaneously with high-dose cytarabine as part of the conditioning regimen for advanced MDS based on these findings, and the 5-year overall survival rate of 14 patients was 75.5% with only one case of disease relapse.¹⁶ The present study, which is a single institute evaluation of more patients, including HSCT recipients from alternative donors, examined the efficacy and safety of a G-CSF-combined high-dose cytarabine regimen for advanced MDS.

Patients and methods

Patients and diagnoses

The present study was a retrospective evaluation of patients with advanced MDS who underwent allogeneic HSCT at Keio University Hospital between May 1995 and September 2005 after being conditioned with total body irradiation (TBI) and G-CSF-combined high-dose cytarabine as described below. During this study period, all patients who underwent allogeneic HSCT for advanced MDS were conditioned with this regimen except for patients who underwent allogeneic HSCT from unrelated donors before June 2000. This cohort included four patients discussed in our previous report.¹⁶ The diagnosis of MDS subtypes was based on the French-American-British classification. Advanced MDS was defined as refractory anemia with excess blasts (RAEB), RAEB in transformation (RAEB-t), AML (more than 30% blasts in the bone marrow or peripheral blood) that had evolved from a preceding phase of MDS (AML-MDS) or chronic myelomonocytic leukemia. Patients with therapy-related MDS were excluded.

Conditioning regimen

TBI (12 Gy) was administered in six doses of 2 Gy each, followed by cytarabine at a dose of 3 g/m², which was administered intravenously over 2 h every 12 h for four consecutive days, as previously reported.^{11, 16, 17} This conditioning regimen was originally used in a pilot study for patients with AML.¹¹ Recombinant human G-CSF (lenograstim) was given by continuous infusion at a daily dose of 5 g/kg, starting 12 h before the first dose of cytarabine and continuing until the last dose of cytarabine. All patients received steroid eye drops for the prophylaxis of keratoconjunctivitis owing to the cytarabine. No patients received antithymocyte globulin as part of the conditioning regimen.

HSCT procedure and supportive care

Two days after the completion of cytarabine and G-CSF administration, the patients received bone marrow transplantation or peripheral blood stem cell transplantation. The types of donor and human leukocyte antigen (HLA) compatibility were HLA-A, -B or -DR identical sibling, or HLA-A, -B or -DR serologically matched unrelated donor. T-cell depletion of the graft was not performed in any of the patients. For the prophylaxis of graft-versus-host disease (GVHD), the patients received cyclosporine A (CSA: 3 mg/kg i.v.) or tacrolimus (0.03 mg/kg iv) with short-term methotrexate (15 mg/m² on day 1, and 10 mg/m² on days 3 and 6). Recipients of bone marrow from an unrelated donor received additional methotrexate (10 mg/m²) on day 11. Both acute and chronic GVHD were diagnosed and graded on the basis of the published criteria.^{18, 19} Each patient was isolated in a laminar air flow room and received antibiotics and antifungal agents orally. The administration of lenograstim at a dose of 5 g/kg was initiated 1 day after HSCT and continued until neutrophil recovery was achieved. Regimen-related toxicities were assessed and graded according to the National Cancer Institute Common Toxicity Criteria (version 2.0).

Statistical analysis

Overall survival, disease-free survival, relapse and non-relapse mortality curves were calculated by the Kaplan–Meier method.

Results

Patients

The medical records of a total of 22 patients were evaluated. The patient characteristics are shown in Table 1. Of our 22 patients, 10 were diagnosed with RAEB, two with RAEB-t, six with AML-MDS and four with CMML. The number of blasts immediately before transplantation exceeded 5% of bone marrow cells in all but three patients, and exceeded 30% in six patients. Twelve patients received stem cells from an HLA-identical sibling donor (bone marrow in nine cases, peripheral blood cells in three) and 10 patients received bone marrow from a serologically HLA-matched unrelated donor.

Table 1 - Patient characteristics (n=22).

Full table

Regimen-related toxicities and engraftment

Regimen-related toxicities are summarized in Table 2. Toxicities were generally well tolerated. We experienced toxicities of grades 3–4: hepatotoxicity (n=3) including one case of fatal hepatic veno-occlusive disease (VOD), mucositis (n=3) and conjunctivitis/keratitis (n=6).

Table 2 - Regimen-related toxicities.

Full table

Of the present 22 patients, 21 achieved neutrophil engraftment (an absolute neutrophil count exceeding 0.5 10⁹/l) between days 14 and 28 after transplantation (median, day 20). The remaining patient died of hepatic VOD and could not be evaluated for engraftment.

GVHD

Grades II to IV acute GVHD developed in 14 patients (eight with HLA-identical sibling donors, six with HLA-matched unrelated donors) and chronic GVHD developed in nine of 20 evaluable patients. Acute and chronic GVHD were successfully treated with the addition of glucocorticoids to cyclosporine or tacrolimus in all patients but one, who died of extensive-type chronic GVHD involving the lungs on day 314 after transplantation.

Survival, disease-free survival and relapse

At the time of writing, 17 of 22 patients are alive, and 16 patients remain disease-free between 12 and 138 months after transplantation (median, 60.6 months). Three patients suffered disease relapse on days 53 (RAEB), 518 (AML-MDS) and 373 (RAEB-t). Two of these three patients then underwent a second transplantation, but both again experienced disease relapse after the second transplantation. The causes of death included disease progression (n=2), hepatic VOD (n=1), bacterial infection (n=1) and extensive-type chronic GVHD (n=1). The 5-year estimated overall survival, disease-free survival, relapse and non-relapse mortality rates were 76.7, 72.2, 16.0 and 14.1%, respectively (Figure 1).

Figure 1.

Kaplan–Meier estimates of (a) overall survival rate, (b) disease-free survival rate, (c) relapse rate and (d) non-relapse mortality rate. The+indicates a censored patient.

Full figure and legend (34K)

Discussion

With the improvement of supportive care for allogeneic HSCT, transplant-related mortality has decreased.^{4, 8} However, disease relapse still remains the most important factor interfering with the success of allogeneic HSCT for MDS. The reported relapse rate after allogeneic HSCT for MDS ranges from 23 to 48%.^{1, 2, 3, 4, 5, 6, 7, 8} These reported relapse rates correspond to all MDS patients, including those with refractory anemia or refractory anemia with ringed sideroblasts, and thus the relapse rate is reported to be much higher (41–67%) in patients with advanced MDS (with excessive blasts).^{1, 2, 3, 4, 5, 6, 7, 8} Therefore, a reduction in post-transplant disease relapse in advanced MDS patients could directly improve transplant outcomes. G-CSF has been reported to increase the susceptibility of leukemic cells to cytarabine in vitro by recruiting quiescent leukemic cells into the cell cycle.^{9, 10, 11} In this context, several reports have shown the efficacy of the combination of G-CSF with cell-cycle-specific chemotherapeutic agents such as cytarabine in refractory myeloid malignancies.^{12, 13, 14, 15} In a randomized trial, it has been shown that addition of G-CSF to cytarabine-based induction chemotherapy for AML patients significantly contributes to a higher rate of disease-free survival owing to the reduced rate of relapse.¹⁵ In an HSCT setting, we previously reported the results of 14 patients in two institutes, who underwent allogeneic HSCT from an HLA-identical sibling after being conditioned with TBI and G-CSF-combined high-dose cytarabine; in these cases, a high disease-free survival rate of 67.7% was demonstrated.¹⁶ In the present long-term follow-up study conducted at a single institute, which included a greater number of patients with advanced MDS including patients who received grafts from unrelated donors, the 5-year disease-free survival rate was 72.2% with a relapse rate of only 16.0%. This relapse rate is somewhat lower than those reported in the studies reported by other investigators.^{1, 2, 3, 4, 5, 6, 7, 8} Furthermore, non-relapse mortality rate, which could affect the survival rate, was identical to that in the other report.²⁰ Therefore, together with the results of our previous report, the present results strongly suggest that a conditioning regimen including G-CSF-combined high-dose cytarabine could effectively reduce disease relapse and contribute to a better survival rate in patients with advanced MDS after allogeneic HSCT.

The previously reported studies used TBI or busulfan plus cyclophosphamide as a myeloablative conditioning regimen for allogeneic HSCT from an alternative donor.^{1, 2, 3, 4, 5, 6, 7, 8} In the present study, 10 patients received HSCT from a serologically HLA-matched unrelated donor, and hematopoietic engraftment was successfully achieved in these patients, suggesting that our regimen without cyclophosphamide could provide sufficient immunosuppressive effects to allow sustained engraftment even in HSCT from an unrelated donor.

We conclude that TBI with G-CSF-combined high-dose cytarabine is a promising conditioning regimen of allogeneic HSCT for patients with advanced MDS and that it does not increase regimen-related toxicities. Future randomized study is required to evaluate the efficacy of combining G-CSF with cytarabine to reduce the incidence of post-transplant disease relapse.

References

1. Sutton L, Chastand C, Ribaud P, Jouet J-P, Kuentz M, Attal M et al. Factors influencing outcome in de novo myelodysplastic syndromes treated by allogeneic bone marrow transplantation: a long-term study of 71 patients. Blood 1996; 88: 358–365. | PubMed | ChemPort |
2. Runde V, De Witte T, Arnold R, Gratwohl A, Hemans J, Van Biezen A et al. Bone marrow transplantation from HLA-identical siblings as first-line treatment in patients with myelodysplastic syndromes: early transplantation is associated with improved outcome. Bone Marrow Transplant 1998; 21: 255–261. | Article | PubMed | ChemPort |
3. Sierra J, Perez WS, Rozman C, Carreras E, Klein JP, Rizzo JD et al. Bone marrow transplantation from HLA-identical siblings as treatment for myelodysplasia. Blood 2002; 100: 1997–2004. | PubMed | ISI | ChemPort |
4. De Witte T, Hermans J, Vossen J, Bacigalup A, Meloni G, Jacobsen N et al. Haematopoietic stem cell transplantation for patients with myelodysplastic syndromes and secondary acute leukaemias: a report on behalf of the Chronic Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT). Br J Haematol 2000; 110: 620–630. | Article | PubMed | ISI | ChemPort |
5. Deeg HJ, Storer B, Slattery JT, Anasetti C, Doney KC, Hansen JA et al. Conditioning with targeted busulfan and cyclophosphamide for hemopoietic stem cell transplantation from related and unrelated donors in patients with myelodysplastic syndrome. Blood 2002; 100: 1201–1207. | Article | PubMed | ISI | ChemPort |
6. Anderson JE, Anasetti C, Appelbaum FR, Schoch G, Gooley TA, Hasen JA et al. Unrelated donor marrow transplantation for myelodysplasia (MDS) and MDS-related acute myeloid leukaemia. Br J Haematol 1996; 93: 59–67. | Article | PubMed | ChemPort |
7. Arnold R, De Witte T, Van Biezen A, Hermans J, Jacobsen N, Runde V et al. Unrelated bone marrow transplantation in patients with myelodysplastic syndromes and secondary acute myeloid leukemia: an EBMT survey. Bone Marrow Transplant 1998; 21: 1213–1216. | Article | PubMed | ISI | ChemPort |
8. Castro-Malaspina H, Harris RE, Gajewski J, Ramsay N, Collins R, Dharan B et al. Unrelated donor marrow transplantation for myelodysplastic syndromes: outcome analysis in 510 transplants facilitated by the National Marrow Donor Program. Blood 2002; 99: 1943–1951. | Article | PubMed | ISI | ChemPort |
9. Miyauchi J, Kelleher CA, Wang C, Minkin S, McCuloch EA. Growth factors influence the sensitivity of leukemic stem cells to cytosine arabinoside in culture. Blood 1989; 73: 1272–1278. | PubMed | ISI | ChemPort |
10. Waga K, Furusawa S, Nagashima S, Saito K, Shishido H. Comparative effects of G-CSF, GM-CSF, and IL-3 on cytosine arabinoside- and daunorubicin-mediated cytotoxicity of acute myeloid leukemia cells and normal myeloid progenitors. Int J Hematol 1992; 56: 17–27. | PubMed | ChemPort |
11. Takahashi S, Okamoto S-I, Shirafuji N, Ikebuchi K, Tani K, Shimane M et al. Recombinant human glycosylated granulocyte colony-stimulating factor (rhG-CSF)-combined regimen for allogeneic bone marrow transplantation in refractory acute myeloid leukemia. Bone Marrow Transplant 1994; 13: 239–245. | PubMed | ChemPort |
12. Tafuri A, De Felice L, Petrucci MT, Grazia M, Mascolo MG, Ricciardi MR et al. Multidrug resistance expression and proliferative studies in poor risk acute myeloid leukemia treated with the FLAG (G-CSF plus fludarabine and Ara-C) regimen. Cytokine Mol Ther 1995; 1: 301–307. | ChemPort |
13. Estey F, Thall P, Andreeff M, Beran M, Kantarjian H, O'Brien S et al. Use of granulocyte colony-stimulating factor before, during, and after fludarabine plus cytarabine induction therapy of newly diagnosed acute myelogenous leukemia or myelodysplastic syndromes: comparison with fludarabine plus cytarabine without granulocyte colony-stimulating factor. J Clin Oncol 1994; 12: 671–678. | PubMed | ChemPort |
14. Saito K, Nakamura Y, Aoyagi M, Waga K, Yamamoto K, Aoyagi A et al. Low-dose cytarabine and aclarubicin in combination with granulocyte colony-stimulating factor (CAG regimen) for previously treated patients with relapsed or primary resistant acute myelogenous leukemia (AML) and previously untreated elderly patients with AML, secondary AML, and refractory anemia with excess of blasts in transformation. Int J Hematol 2000; 71: 238–244. | PubMed | ChemPort |
15. Lowenberg B, van Putten W, Theobald M, Gmur J, Verdonck L, Sonneveld P et al. Effect of priming with granulocyte colony-stimulating factor on the outcome of chemotherapy for acute leukemia. N Engl J Med 2003; 349: 743–752. | Article | PubMed | ISI |
16. Okamoto S, Takahashi S, Wakui M, Ishida A, Tanosaki R, Ikeda Y et al. Treatment of advanced myelodysplastic syndrome with a regimen including recombinant human granulocyte colony-stimulating factor preceding allogeneic bone marrow transplantation. Br J Haematol 1999; 104: 569–573. | Article | PubMed | ChemPort |
17. Takahashi S, Oshima Y, Okamoto S-I, Nishiwaki K, Nagayama H, Inoue T et al. Recombinant human granulocyte colony-stimulating factor (G-CSF) combined conditioning regimen for allogeneic bone marrow transplantation (BMT) in standard-risk myeloid leukemia. Am J Hematol 1998; 57: 303–308. | Article | PubMed | ChemPort |
18. Przepiorka D, Weisdorf D, Martin P, Klingemann HG, Beatty P, Hows J et al. Consensus conference on acute GVHD grading. Bone Marrow Transplant 1995; 15: 825–828. | PubMed | ISI | ChemPort |
19. Shulman HM, Sullivan KM, Weiden PL, McDonald GB, Striker GE, Sale GE et al. Chronic graft-versus-host syndrome in man: a long-term clinicopathologic study of 20 Seattle patients. Am J Med 1980; 69: 204–217. | Article | PubMed | ISI | ChemPort |
20. Nakai K, Kanda Y, Fukuhara S, Sakamaki H, Okamoto S, Kodera Y et al. Value of chemotherapy before allogeneic hematopoietic stem cell transplantation from an HLA-identical sibling donor for myelodysplastic syndrome. Leukemia 2005; 19: 396–401. | Article | PubMed | ChemPort |