Hematologic Recovery after Tandem High-Dose Chemotherapy and Autologous Stem Cell Transplantation in Children with High-Risk Solid Tumors

Although the number of studies using tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/autoSCT) for the treatment of high-risk pediatric solid tumors has been increasing, documentation of hematologic recovery after tandem HDCT/autoSCT is very limited. For this reason, we retrospectively analyzed the hematologic recovery of 236 children with high-risk solid tumors who underwent tandem HDCT/autoSCT. The median numbers of CD34+ cells transplanted during the first and second HDCT/autoSCT were 4.3 x 10(6)/kg (range 0.6-220.2) and 4.1 x 10(6)/kg (range 0.9-157.6), respectively (P = 0.664). While there was no difference in neutrophil recovery between the first and second HDCT/autoSCT, platelet and RBC recoveries were significantly delayed in the second HDCT/autoSCT (P < 0.001 and P < 0.001, respectively). Delayed recovery in the second HDCT/autoSCT was more prominent when the number of transplanted CD34+ cells was lower, especially if it was < 2 x 10(6)/kg. A lower CD34+ cell count was also associated with increased RBC transfusion requirements and a higher serum ferritin level after tandem HDCT/autoSCT. More CD34+ cells need to be transplanted during the second HDCT/autoSCT in order to achieve the same hematologic recovery as the first HDCT/autoSCT.

Hematologic Recovery and Clinical Outcomes according to Cell Dose after HLA-matched Sibling Allogeneic Bone Marrow Transplantation

BACKGROUND: There has been changed in estimation of the stem cell content of the graft for several decades. However, there is not always correlating the transplanted cell dose with hematologic recovery, and there are few reports in human leukocyte antigen (HLA)-matched sibling allogeneic bone marrow transplantation (AlloBMT) in Korea. The purpose of this study is to report the influence of number of transplanted cell dose on hematologic recovery and the clinical outcomes in HLA-matched sibling AlloBMT. METHODS: Between June 1999 and March 2004, 31 AlloBMT from HLA-matched sibling donor was done in patients with hematologic malignancy. All patients were conditioned with busulfan and cyclophosphamide. Short course methotrexate and cyclosporine regimen was used for prophylaxis of graft-versus-host disease. We analyzed hematologic recovery time and clinical outcomes according to transplanted cell dose. RESULTS: There were 16 male and 15 female patients, with a median age of 34 years (range, 16~48). Underlying diseases were 17 acute myeloid leukemia, 4 acute lymphoblastic leukemia, 3 myelodysplastic syndrome (high-risk), and 7 chronic myelogenous leukemia. The median number of total nucleated cell (TNC), mononuclear cell (MNC) and CD34+ cell infused was 3.95x10(8)/kg (range, 1.67~7.30x10(8)/kg), 0.65x10(8)/kg (range, 0.11~2.50x10(8)/kg), and 2.32x106/kg (range, 0.35~7.45x106/kg), respectively. The median days of neutrophil and platelet engraftment (ANC>500/microliter and platelet > 20,000/L without transfusion) were 15 (range, 10~19), 16 (range, 7~37), respectively. Relationship between the rate of neutrophil engraftment and the number of infused TNC was only statistically significant (P=0.038, R2=0.328). This study showed survival benefit with the increment of CD34+ cell dose without significance statistically (P=0.082). CONCLUSION: Although the dose of the number of transplanted MNC and CD34+ cells had no influence on granulocyte or platelet recovery, the number of TNC had only a beneficial effect on neutrophil recovery. The transplanted dose of CD34+ cells, rather than those of TNC and MNC may be related with better survival.