Kinetics of hemopoietic recovery after peripheral blood stem cell transplantation: impact of stem cell purification and G-CSF

We investigated the role of stem cell purification and G-CSF (early vs. delayed vs. no G-CSF) administration on hemopoietic recovery and supportive care requirements after stem cell transplantation. Thirty-two patients submitted to autologous CD34(+) peripheral blood stem cell transplantation (PBSCT) were studied, and data were compared to patients undergoing unfractionated peripheral blood stem cell transplantation (uPBSCT) matched for age, disease, and conditioning regimen. Except for PMN, hemopoietic recovery was significantly slower and supportive care requirements were significantly higher after CD34(+) PBSCT. Median time to PMN >0.5 x 10(9)/l was 13 days (range 9-27) and 13 d (range 9-23); reticulocytes (Ret) >1% was 14.5 d (range 12-34) and 12 d (range 10-27); high-fluorescence reticulocytes (HFR) >5% was 12 d (range 9-26) and 9 d (range 7-11); platelets >50 x 10(9)/l and >100 x 10(9)/l was 20 d (range 10-240), 12 d (range 9-60) and 33 d (range 15-720), 15 d (range 11-210). When the analysis was performed on subgroups of patients (early/delayed/no G-CSF), early G-CSF significantly promoted PMN recovery (>0.5 x 10(9)/l and >1.0 x 10(9)/l) compared to no G-CSF, without affecting RBCs or platelet recovery. Delayed G-CSF did not improve PMN recovery compared to patients not receiving G-CSF, did not result in a significant reduction of drug requirements, and had a negative impact on erythroid and platelet recovery. In conclusion, these preliminary data suggest that G-CSF is useful if given early after CD34(+) PBSCT. CD34(+) PBSCT may overall require a significant increase of resource utilization that should be outweighed by proven clinical benefit.     

Autologous bone marrow transplantation in non-Hodgkin's lymphoma patients: effect of a brief course of G-CSF on harvest and recovery.

This study compares harvest and hematological recovery data of 100 lymphoma patients who underwent BM harvest either after a short course of G-CSF (16 microg/kg for 3 days) (n = 57) or in steady-state conditions (n = 43). G-CSF allowed the attainment of a significantly higher median number of total nucleated cells x 10(8)/kg (4.4, range 1.4-17, vs 2.1, range 0.6-4.2; P < 0.0001), mononuclear cells x 10(8)/kg (0.55, range 0.20-1.4, vs 0.41, range 0.15-0.76, P < 0.0001) and CFU-GM/ml (310, range 10-5500, vs 80, range 10-3800, P = 0.008), with lower volumes of blood collected (17.5 ml/kg, range 8-31 vs 21.0, range 15-30, P = 0.0001). Hematological recovery was faster in patients who received pre-treated BM (median time to PMN >0.5 x 10(9)/l and to platelets >20 x 10(9)/l was 12, range 10-14, and 13, range 10-18, days, respectively) than in those autotransplanted with steady-state BM (median time to PMN >0.5 x 10(9)/l and to platelets >20 x 10(9)/l 13, range 10-18 and 14, range 10-20 days, respectively, P = 0.004 and P = 0.01). Transfusional requirement was significantly different and patients of the G-CSF group needed shorter hospitalization (17 days, range 12-24, vs 20 days, range 14-32; P = 0.02). These data suggest that treating patients with G-CSF before BM harvest improves the quality of the harvest and accelerates engraftment and hematological recovery.     

Factors influencing hematopoietic recovery after autologous blood stem cell transplantation in patients with acute myeloblastic leukemia and with non-myeloid malignancies

Factors influencing hematopoietic recovery (HR) after autologous blood stem cell transplantation (ABSCT) were analyzed in 73 patients with various non-myeloid malignancies (NMM), and in 58 patients with acute myeloblastic leukemia (AML). Peripheral blood stem cells were collected following mobilization with chemotherapy, granulocyte colony-stimulating factor (G-CSF), or chemotherapy plus G-CSF. The conditioning regimen used consisted of either chemotherapy alone (112 cases) or chemotherapy plus total body irradiation (19 cases). The median number of colony-forming units granulocyte-macrophage (CFU-GM) was similar in both groups of patients, with the median number of CD34(+) cells infused being higher in the AML group (5.4 vs 4 x 10(6)/kg; P = 0.03). Median time neutrophils >0.5 x 10(9)/l was 13 days in both groups, and median time to a platelet count >20 x 10(9)/l was longer in AML patients (14 vs 12 days; P = 0.01). In multivariate analysis, the only factors affecting neutrophil recovery in the NMM group were the CD34+ cell number (continuous model) and the CFU-GM dose (categorized model) infused, whereas for platelet recovery, previous chemotherapy also remained significant. In the AML group, the only factors significantly affecting the speed of neutrophil recovery were dose of CD34+ cells administered and the patient's age. As for platelet recovery, only the progenitor dose administered remained significant. In the NMM group, the most discriminating cut-off values for a rapid neutrophil and platelet recovery were 1.5 x 10(6) and 2.5 x 10(6) CD34+ cells/kg, respectively, and for AML patients these figures were 1.5 x 10(6) and 4 x 10(6) CD34+ cells/kg, respectively. Our results confirm the slower HR after ABSCT in AML, and highlight the importance of progenitor cell dose in accelerating HR after ABSCT.     

A prospective randomized study of clinical and economic consequences of using G-CSF following autologous peripheral blood progenitor cell (PBPC) transplantation in children

This prospective and randomized study was conducted to evaluate clinical and economic consequences of using granulocyte colony-stimulating factor (G-CSF) following autologous peripheral blood progenitor cell (PBPC) transplantation in children. Between January 1999 and December 2003, 117 patients underwent autologous PBPCT: 51 patients received G-CSF following PBPCT, while 66 patients did not receive G-CSF. Median time to absolute neutrophil count > 0.5 x 10(9)/l was 10 days in the treatment group and 11 days in the control group (P < 0.009). The median time to platelets >20 x 10(9)/l was 12 days in both groups (P = NS). The median time to platelets >50 x 10(9)/l was 15 days in the G-CSF group and 14 days in the control group (P<0.005). In patients who received <5 x 10(6)/kg CD34+ cells, the median time to platelets >20 x 10(9)/l and >50 x 10(9)/l was similar with or without G-CSF (12 and 15 days, respectively). Platelet transfusion requirements were lower in the control group (2 vs 3 U in G-CSF group). There was a trend towards higher total costs with G-CSF: 8146.82 Euros and 7873.34 Euros with and without G-CSF, respectively (P = 0.1). Our data suggest that there is no indication of the standard application of G-CSF in children following PBPC transplantation. The only possible indication is the group of patients with a lower yield of CD34+ cells.     

Blood stem cell collection using chemotherapy with or without systematic G-CSF: experience in 52 patients with multiple myeloma.

Harvesting of peripheral blood stem cells (PBSCs) following chemotherapy and G-CSF administration is currently performed for hematological therapies. However, a procedure based on the use of a large quantity of G-CSF is relatively costly. Therefore, we retrospectively compared the effects of two PBSC mobilization procedures in a population with recently diagnosed multiple myeloma. The first procedure consisted of chemotherapy and systematic G-CSF administration (group 1: 24 patients). The second consisted of chemotherapy alone, G-CSF having been administered only in the case of failure of PBSC mobilization or delayed white blood cell (WBC) recovery (group 2: 28 patients). Leukapheresis was performed when WBC recovery reached 1 x 10(9)/l if the peripheral blood CD34+ cell count was over 10/microl. Leukapheresis was maintained until a total of 2.5 x 10(6) CD34+ cells/kg was harvested. A significant difference was observed between the two groups only in regard to the median period of WBC recovery (delayed for group 2) and the number of CD34+ cells/kg collected on the first leukapheresis (higher for group 1) but not to the proportion of patients with failure of PBSC collection. Ten group 2 patients, who had insufficient CD34+ cells after WBC recovery or delayed WBC recovery, received G-CSF which resulted in sufficient PBSC harvesting in nine. To obtain a sufficient CD34+ cell level, the patients without systematic G-CSF administration had more leukaphereses (2.1 vs 1.5) but the mean consumption of G-CSF per patient was eight times less than in the other group. Nonsystematic use of G-CSF before WBC recovery or preferentially its introduction just after, could be an interesting economical alternative in PBSC mobilization but should be assessed by a prospective controlled study of cost/efficacy.     

Long-term hematopoietic engraftment after autologous peripheral blood progenitor cell transplantation in pediatric patients: effect of the CD34+ cell dose

BACKGROUND AND OBJECTIVES: We analyzed the relationship between long-term hematopoietic recovery and the number of CD34+ cells infused in order to determine the optimal dose of CD34+ cells for rapid and stable engraftment. PATIENTS AND METHODS: Between November 1993 and December 1998, 96 consecutive autologous transplantations were performed in 92 pediatric patients with different malignancies. Peripheral blood progenitor cells (PBPC) were mobilized by G-CSF alone (12 microg/kg/day s.c., Neupogen((R)); Amgen, Thousand Oaks, Calif., USA) and collected using a Cobe Spectra blood cell separator (Cobe, Denver, Colo., USA) through a central venous catheter with double lumen. The CD34+ cell contents of apheresis products were assessed by means of flow-cytometric analysis using an Epics Elite flow cytometer (Coulter, USA). RESULTS: The median number of CD34+ cells infused was 3.2 x 10(6)/kg (range 0.17-44.4). The median times for short-term engraftment (neutrophil count >0.5 x 10(9)/l and platelet count >20 x 10(9)/l) was 9 (range: 7-16) and 13 days (range: 7-91), respectively. The median times for long-term engraftment (platelet count >50 x 10(9)/l and >100 x 10(9)/l) was 21 (range: 10-249) and 45 days (range: 12-288). When the infused CD34+ cell dose was >/=5 x 10(6)/kg (median 7.99, range 5.01-44.4), there was a statistically significant increase in the rate of short- and long-term hematopoietic recovery compared to patients transplanted with a lower number of CD34+ cells (p < 0.0001). The earlier recovery in the high CD34+ cell group resulted in less transfusional support, fewer days on intravenous antibiotics and shorter hospitalization. CONCLUSIONS: This study confirms that G-CSF-mobilized PBPC provide rapid short- and long-term hematopoietic engraftment in pediatric patients undergoing autologous transplantation if a CD34+ cell dose >/=5.0 x 10(6)/kg is infused. As this PBPC dose seems to have clinical and potentially economic implications, it should be considered the optimal dose for apheresis.     

A randomized,multicenter study of G-CSF starting on day +1 vs day +5 after autologous peripheral blood progenitor cell transplantation

In order to assess the effect of delaying G-CSF administration after autologous peripheral blood progenitor cell (PBPC) transplantation on the duration of neutropenia, 87 patients were randomized to receive G-CSF 5 microg/kg/day starting on day +1 (n = 45) or +5 (n = 42) following PBPC transplantation, until recovery of the neutrophils. The duration of neutropenia (<0.5 x 10(9)/l) was shorter in the day +1 group (7 vs 8 days; P = 0.02), especially in patients receiving melphalan 200 mg/m(2) and CD34(+) cell doses >3.0 x 10(6)/kg. These patients had a later onset of neutropenia after transplant. There were no differences in time to neutrophil and platelet engraftment, or in the incidence of fever and documentation of infection. Although the duration of antibiotic therapy (7 vs 10.5 days; P = 0.01) and time to hospital discharge (13 vs 15 days; P = 0.02) were shorter in the day +1 group, these differences could not be predicted by the day of G-CSF initiation in multivariate analysis. Starting G-CSF on day +1 does not result in faster neutrophil engraftment but in later onset and consequently, slightly shorter duration of neutropenia in patients who receive melphalan 200 mg/m(2) and CD34(+) cell doses >3.0 x 10(6)/kg.     

Effects of short-term administration of G-CSF (filgrastim) on bone marrow progenitor cells: analysis of serial marrow samples from normal donors

To determine the effect of G-CSF administration on both the total number of CD34+ cells and the primitive CD34+ subsets in bone marrow (BM), we have analyzed BM samples serially obtained from 10 normal donors in steady-state and during G-CSF treatment. Filgrastim was administered subcutaneously at a dosage of 10 microg/kg/day (n = 7) or 10 microg/kg/12 h (n = 3) for 4 consecutive days. Peripheral blood sampling and BM aspirates were performed on day 1 (just before G-CSF administration), day 3 (after 2 days of G-CSF), and day 5 (after 4 days of G-CSF). During G-CSF administration, a significant increase in the total number of BM nucleated cells was observed. The percentage (range) of CD34+ cells decreased in BM from a median of 0.88 (0.47-1.44) on day 1 to 0.57 (0.32-1.87), and to 0.42 (0.16-0.87) on days 3 and 5, respectively. We observed a slight increase in the total number of BM CD34+ cells on day 3 (0.66 x 10(9)/l (0.13-0.77)), and a decrease on day 5 (0.23 x 10(9)/l (0.06-1.23)) as compared with steady-state (0.40 x 10(9)/l (0.06-1.68)). The proportion of primitive BM hematopoietic progenitor cells (CD34+CD38-, CD34+HLA-DR-, CD34+CD117-) decreased during G-CSF administration. In parallel, a significant increase in the total number of CD34+ cells in peripheral blood was observed, achieving the maximum value on day 5. These results suggest that in normal subjects the administration of G-CSF for 5 days may reduce the number of progenitor cells in BM, particularly the most primitive ones.     

Mobilization of CD34+ cells in elderly patients (>/= 70 years) with multiple myeloma: influence of age,prior therapy,platelet count and mobilization regimen

The mobilization of peripheral blood stem cells was studied in 984 multiple myeloma patients, including 106 patients aged >/= 70 years. Increasing age correlated inversely with CD34+ yield (P < 0.0001), but also with >/= 12 months of prior standard chemotherapy (P = 0.0001), < 200 x 10(9)/l platelets (P = 0.0006) premobilization and mobilization with growth factors only (P = 0.0001). After controlling for these age covariates, multivariate analysis identified /= 200 x 10(9)/l premobilization as favourable variables (both P < 0.0001), while increasing patient age remained an unfavourable factor (P = 0.0009). With both favourable variables, 85% of elderly patients collected >/= 4 x 10(6)/kg CD34+ cells in a median of one collection. The effect of age was incremental with no age threshold showing acceleration in the decline of CD34+ yield. Chemotherapy significantly increased CD34+ yield compared with growth factors only. However, the subgroup of patients with > 12 months prior therapy and premobilization platelet count < 200 x 10(9)/l mobilized as many CD34+ cells with granulocyte colony-stimulating factor (G-CSF) alone as with chemotherapy and haematopoietic growth factors. Increasing patient age had no effect on post-transplant neutrophil recovery, but significantly delayed platelet recovery (>/= 50 x 10(9)/l) if < 2 x 10(6)/kg CD34+ cells were infused, but this effect was eliminated completely with infusion of >/= 4 x 10(6)/kg CD34+ cells. Increasing age adversely affected CD34+ yield even with limited premobilization therapy, indicating that early collection is important in elderly patients.     

Recombinant human granulocyte colony-stimulating factor (rh-G-CSF) may accelerate hematopoietic recovery after HLA-identical sibling allogeneic peripheral blood stem cell transplantation

We studied the effects of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematopoietic recovery and clinical outcome in patients undergoing allogeneic peripheral blood stem cell (PBSC) transplantation. Fifty-six patients with hematological malignancies who underwent allogeneic PBSC transplantation between 1995 and 1998 were entered into this study. Twenty-eight patients who received daily G-CSF from day +1 after allogeneic PBSC transplantation until the absolute neutrophil count (ANC) reached >0.5 x 10(9)/l for 3 consecutive days were compared with 28 patients (control group) who did not receive G-CSF in a non-randomized manner. The study group and the control group were comparable with respect to baseline patient and transplantation characteristics. Median times to ANC of >0.5 x 10(9)/l and 1 x 10(9)/l with or without G-CSF were 12 days (range 8-21), 13 days (10-32) (P = 0.04) and 13 days (9-21), 15 days (11-44) (P = 0.02), respectively. Median times to reach a platelet count of >20 x 10(9)/l with and without G-CSF were 11 days (0-20) and 13 days (9-26), respectively (P = 0.03). The incidence of febrile episodes was significantly lower with G-CSF, 75% vs 100% (P = 0.008). Patients receiving G-CSF had less grade III-IV mucositis than those who did not receive G-CSF (P = 0.01). There was also no increase in the incidence and severity of acute GVHD in patients using G-CSF (P = 0.22). Although the number of relapsing patients was greater in the G-CSF group (seven vs three patients), this was not statistically significant (P = 0.24). Disease-free and overall survival rates did not differ between the two groups (P = 0.58 and 0.53, respectively). The administration of G-CSF after allogeneic PBSC transplantation provided faster neutrophil and platelet engraftment associated with less severe mucositis and less febrile episodes.     

Peripheral blood stem cell transplantation as an alternative to autologous marrow transplantation in the treatment of acute myeloid leukemia?

The clinical use of autologous marrow transplantation in acute myeloid leukemia (AML) has been hampered by the inability to collect adequate numbers of cells after remission induction chemotherapy and the notably delayed hematopoietic regeneration following autograft reinfusion. Here we present a study in which the feasibility of mobilizing stem cells was investigated in newly diagnosed AML. Among 96 AML patients, 76 patients (79%) entered complete remission. Mobilization was undertaken with low dose and high dose schedules of G-CSF in 63 patients, and 54 patients (87%) were leukapheresed. A median of 2.0 x 10(6) CD34+ cells/kg (range 0.1-72.0) was obtained in a median of three leukaphereses following a low dose G-CSF schedule (150 microg/m2) during an average of 20 days. Higher dose regimens of G-CSF (450 microg/m2 and 600 microg/m2) given during an average of 11 days resulted in 28 patients in a yield of 3.6 x 10(6) CD34+ cells/kg (range 0-60.3) also obtained following three leukaphereses. The low dose and high dose schedules of G-CSF permitted the collection of 2 x 10(6) CD34-positive cells in 46% and 79% of cases respectively (P = 0.01). Twenty-eight patients were transplanted with a peripheral blood stem cell (PBSC) graft and hemopoietic repopulation was compared with the results of a previous study with autologous bone marrow. Recovery of granulocytes (>0.5 x 10(9)/l, 17 vs 37 days) and platelets (>20 x 10(9)/l; 26 vs 96 days) was significantly faster after peripheral stem cell transplantation compared to autologous bone marrow transplantation. These results demonstrate the feasibility of PBSCT in the majority of cases with AML and the potential advantage of this approach with respect to hemopoietic recovery.     

Changes in endogenous TPO levels during mobilization chemotherapy are predictive of CD34+ megakaryocyte progenitor yield and identify patients at risk of delayed platelet engraftment post-PBPC transplant

Patients with delayed platelet recovery post-PBPC transplant (PBPCT) are a high-risk group for thrombocytopenic bleeding and platelet transfusion dependence. Total CD34+ cell dosage has been proposed as the most important factor influencing the rate of platelet recovery. To achieve the shortest time to platelet engraftment, a minimum leukapheresis target of 10x10(6) CD34+ cells/kg was established for 30 patients. Of the 29 evaluable patients, 62% had rapid (group I: time to platelets >20x10(9)/l < or =10 days and 50x10(9)/l < or =14 days) platelet recoveries while 38% had delayed (group II: 20x10(9)/l >10 days and 50x10(9)/l >14 days) recoveries. Groups I and II were compared for: (1) pretreatment variables; (2) mobilizing capability of CD34+ cells and subsets including megakaryocyte (Mk) progenitors; (3) infused dose of these cells at transplant; (4) changes in endogenous levels of Mpl ligand (or TPO) during mobilization and myeloablative chemotherapy. Group II patients received significantly more platelet transfusions (6 vs. 2.1, P = 0.002) post-PBPCT, had a higher proportion of patients with a prior history of BM disease (64% vs. 6%, P = 0.001), and showed a reduced ability to mobilize differentiated (CD34+/38+, CD34+/DR+) and Mk progenitors (CD34+/42a+, CD34+/61+). Only the number of Mk progenitors reinfused at transplant was significantly different between the groups (group II vs. group I: CD34+/42a+ = 1.02 vs. 2.56x10(6)/kg, P = 0.013; CD34+/61+ = 1.12 vs. 2.70x10(6)/kg, P = 0.015). The ability to mobilize Mk progenitors correlated with percentage changes in endogenous levels of TPO from baseline to platelet nadir during mobilization chemotherapy (CD34+/42a+: r = 0.684, P = 0.007; CD34+/61+: r = 0.684, P = 0.007), with group II patients experiencing lower percentage changes. An inverse trend but no correlation was observed between serial TPO levels and platelet counts. TPO levels remained elevated in group II patients throughout a prolonged period of thrombocytopenia (median days to 50x10(9)/l = 25 vs. 11 for group I), indicating that delayed engraftment was not due to a deficiency of TPO but to a lack of Mk progenitor target cells. Our results show that the number of reinfused Mk progenitors is a better predictor of platelet engraftment than total CD34+ cell dosage. Small changes in endogenous TPO levels during mobilization predict for low Mk progenitor yields.     

CD34+ dose-driven administration of granulocyte colony-stimulating factor after high-dose chemotherapy in lymphoma patients

Our goal was to optimize use of granulocyte colony-stimulating factor (G-CSF) after high-dose chemotherapy and autologous peripheral blood stem-cell transplantation in lymphoma patients, limiting G-CSF administration to patients infusing a suboptimal CD34(+) cell number. Of 124 consecutive patients with histologically proven Hodgkin's and non-Hodgkin's lymphoma from January 2001 to June 2004, 60 patients (group 1) given > or = 5 x 10(6)/kg CD34(+) cells received no G-CSF; 64 patients (group 2) given < or = 5 x 10(6)/kg CD34(+) cells received G-CSF from day +5 after stem-cell reinfusion. The median times to reach 0.5 x 10(9)/L and 1.0 x 10(9)/L neutrophils were, respectively, 3 and 4 d shorter in G-CSF group and this difference was statistically significant (P = 0.0014; P = 0.0001). In terms of antibiotic and antimycotic requirements, gastrointestinal toxicity, days of hospitalization, and transfusion requirements, no differences were demonstrated between the two groups. No statistically significant difference was demonstrated for the total number of febrile episodes (52 for group 1; 53 for group 2; P = 0.623) and the median number of febrile days (2 d for both groups). Myeloid reconstitution values for both groups agree with published results for autotransplanted patients treated with G-CSF from 7 to 14 d. Also, major clinical events, antibiotic, antimycotic, and transfusion requirements, and hospital stay were similar to published findings. Our data suggest that G-CSF administration can be safely optimized, used only for patients infused with a suboptimal CD34(+) cell dose.     

Very large amounts of peripheral blood progenitor cells eliminate severe thrombocytopenia after high-dose melphalan in advanced breast cancer patients

We analyzed the relationship between the reinfusion of large or very large amounts of peripheral blood progenitor cells (PBPC) and hematologic toxicity in twenty-one advanced breast cancer patients subjected to a myeloablative dose of melphalan at the end of a high-dose sequential chemotherapy (HDSC) program. We also evaluated the influence of the white blood cell (WBC) count to predict an optimal PBPC harvest after high-dose chemotherapy and growth factor priming. Twenty-one patients with high-risk or metastatic breast cancer sequentially received: high-dose cyclophosphamide (HD-Cy) and G-CSF followed by PBPC harvest, HD-methotrexate plus vincristine, HD-doxorubicin, cisplatin and finally HD-melphalan 200 mg/m2 (HD-L-PAM) followed by PBPC reinfusion. No growth factor was administered after HD-L-PAM. CD34+ cytofluorimetric analysis, WBC count and clonogenic assays were employed to monitor circulating cells and to analyze the PBPC harvest. Correlation between different PBPC doses and hematologic toxicity as well as leukocyte and platelet recovery time was attempted. Patients received a median number of 16 (4-25.1) x 10(6)/kg CD34+ cells, 81.3 (30.8-228) x 10(4)/kg CFU-GM and 4.2 (1.3-7.3) x 10(8)/kg nucleated cells (NC) after HD-L-PAM. The number of days with fewer than 1 x 10(9)/l leukocytes and 20 x 10(9)/l platelets were 6 (range 4-9) and 0 (range 0-3), respectively. The CD34+ cell dose significantly correlated with both platelet count nadir (r = 0.73) and time to 50 x 10(9)/l platelets (r = 0.7), but did not correlate with time to reach more than 1 x 10(9)/l WBC count (r = 0.2). In particular, we found that in 12 patients given very large amounts of CD34+ cells, ranging between 15.8 and 25. 1 x 10(6)/kg (V-LA-CD34+), the platelet nadir count never fell below 20 x 10(9)/l and platelet transfusions were not required. Conversely, nine patients who received only large amounts of CD34+ cells, ranging between 4 and 12 x 10(6)/kg (LA-CD34+), experienced a platelet nadir lower than 20 x 10(9)/l and required 2 days (range 1-4) to achieve independence from platelet transfusions (P = 0.001 and P = 0. 0005). The requirement for packed red blood cells (RBC) was 1.5 vs 3 units in the V-LA-CD34+ and LA-CD34+ groups respectively (P = 0.063). The analysis of 44 PBPC collections demonstrated that 29 aphereses performed with a WBC count <20 x 10(9)/l yielded a mean of 312 +/- 43 x 10(6) CD34+ cells and 1831 +/- 201 x 10(4) CFU-GM, whereas 15 collections performed with WBC count >20 x 10(9)/l yielded 553 +/- 64 x 10(6) CD34+ cells and 3190 +/- 432 x 10(4) CFU-GM (P = 0.004). In conclusion, our data suggests that V-LA-CD34+ eliminates severe thrombocytopenia and platelet transfusion requirements in breast cancer patients subjected to HD-L-PAM, and higher PBPC collections seems to coincide with WBC count higher than 20 x 10(9)/l after HD-Cy and G-CSF mobilization. These results justify a prospective study to establish whether large doses of CD34+ cells result in significant clinical benefits.     

Frequent viral infections and delayed CD4+ cell recovery following CD34+ cell-selected autologous peripheral blood stem cell transplantation

This study compares the reconstitution of T-lymphocyte subsets and the incidence of infections following CD34+ cell-selected autologous peripheral blood stem cell transplantation (PBSCT) (n = 15) and unselected auto-PBSCT (n = 16). In the CD34+ cell-selected auto-PBSCT group, the mean count of CD4+ cells had significantly decreased at 30 days after transplantation compared with pretransplantation, and did not reach the safe minimum level of 0.2 x 10(9)/l even at 90 days after transplantation. Compared with unselected auto-PBSCT, CD4+ cell reconstitution after CD34+ cell-selected auto-PBSCT was significantly delayed within the first 90 days after transplantation. Cytomegalovirus infections developed more frequently after CD34+ cell-selected auto-PBSCT than after unselected auto-PBSCT (nine patients vs. two patients, P = 0.0057). Hemorrhagic cystitis due to adenovirus type 11 infections developed in three patients who underwent CD34+ cell-selected auto-PBSCT. Positive correlation between the counts of reinfused CD34+ cells and the counts of CD4+ cells were found at 90 days after CD34+ cell-selected auto-PBSCT. No significant difference was found in the frequency of viral infections, however, between patients transplanted with > 2 x 10(6)/kg of CD34+ cells and those transplanted with < 2 x 10(6)/kg of CD34+ cells. Careful monitoring for viral infection is necessary after CD34+ cell-selected auto-PBSCT.     

Mobilization of peripheral blood progenitor cells (PBPC) in patients undergoing chemotherapy followed by autologous peripheral blood stem cell transplant (SCT) for high risk breast cancer (HRBC).

We have determined the effect of delayed addition of G-CSF after chemotherapy on PBPC mobilization in a group of 30 patients with high risk breast cancer (HRBC) undergoing standard chemotherapy followed by high-dose chemotherapy (HDCT) and autologous SCT. Patients received FAC chemotherapy every 21 days followed by G-CSF at doses of 5 microg/kg/day starting on day +15 (groups 1 and 2) or +8 (group 3) after chemotherapy. PBPC collections were performed daily starting after 4 doses of G-CSF and continued until more than 2.5 x 10(6) CD34+ cells had been collected. In group 1, steady-state BM progenitors were also harvested and used for SCT. Groups 2 and 3 received PBPC only. The median number of collections was three in each group. Significantly more PB CD34+ cells were collected in patients receiving G-CSF starting on day 8 vs day 15 (9.43 x 10(6)/kg and 6.2 x 10(6)/kg, respectively) (P < 0.05). After conditioning chemotherapy all harvested cells including BM and PBPC were reinfused. Neutrophil and platelet engraftment was significantly faster in patients transplanted with day 8 G-CSF-mobilized PBPC (P < 0.05) and was associated with lower transplant related morbidity as reflected by days of fever, antibiotics or hospitalization (P < 0.05). Both schedules of mobilization provided successful long-term engraftment with 1 year post-transplant counts above 80% of pretransplant values. In conclusion, we demonstrate that delayed addition of G-CSF results in successful mobilization and collection of PBPC with significant advantage of day 8 G-CSF vs day 15. PBPC collections can be scheduled on a fixed day instead of being guided by the PB counts which provides a practical advantage. Transplantation of such progenitors results in rapid short-term and long-term trilineage engraftment.     

Granulocyte colony-stimulating factor mobilized whole blood containing over 0.3 x 106/kg CD34+ cells is a sufficient graft in autologous transplantation for relapsed non-Hodgkin's lymphoma

The feasibility of unprocessed, granulocyte colony-stimulating factor (G-CSF)-mobilized whole blood (WB) as an alternative stem cell source for autologous stem cell transplantation was studied. Forty-seven relapsed non-Hodgkin's lymphoma (NHL) patients entered the study. After two or three ifosfamide, methotrexate and etoposide (IMVP) courses, 1 l of G-CSF-mobilized WB was collected and stored refrigerated for 72 h. Meanwhile, BAM conditioning was given: BCNU (carmustine) 300 mg/m(2), high-dose cytarabine 6000 mg/m(2) and melphalan 140 mg/m(2). Toxicity, haematological recovery and survival were assessed and compared with peripheral blood stem cell transplantation (PBSCT) and bone marrow transplantation (BMT) reference groups. High-dose G-CSF (2 x 12 microg/kg/d) gave the best mobilization results. Haematological recovery was related to the WB CD34+ content. A CD34+ threshold of >or= 0.3 10(6)/kg, obtained in 90% of patients using high-dose G-CSF, correlated with adequate recovery: absolute neutrophil count (ANC) > 0.5 x 10(9)/l: median 12 d (range 9-19). Platelet recovery > 20 and > 50 x 10(9)/l was 19 (11-59) and 30 d (14 not reached) respectively. Overall survival of patients < 60 years was 57% at 4 years and event-free survival was 32%. Survival was comparable with PBSCT and BMT after BEAM (BCNU, etoposide, cytarabine, melphalan). Remarkably, haematological recovery after BAM + WB was rapid and comparable (ANC) or slightly prolonged (platelets) in comparison with BEAM + PBSCT, despite a 10-20 times lower CD34+ cell dose in the WB graft. In conclusion, transplantation of WB containing >or= 0.3 x 10(6)/kg CD34+ cells after BAM conditioning is a safe procedure, and offers a fully equivalent and less costly alternative for PBSC.     

Telomere length predicts neutrophil recovery in the absence of G-CSF after autologous peripheral blood stem cell transplantation

Summary:Haemopoietic regeneration after autologous peripheral blood progenitor cell (PBPC) transplantation can be delayed in some patients despite adequate infusion of CD34(+) cells. This suggests variability in the proliferation potential of the implanted cells, a capacity that may be predicted by their telomere length. To test this theory, telomere length was measured on stored apheresis samples from 36 patients aged 46.6+/-11.1 years, who had undergone successful autologous PBPC transplantation with a median of 5.6 x 10(6)/kg (1.3 x 10(6)-36.1 x 10(6)/kg) CD34(+) cells. The mean PBPC telomere length for the cohort was 9.4+/-2.3 kbp. For patients who did not receive G-CSF post transplantation (n=7), days to absolute neutrophil recovery (ANC), >/=0.1, 0.5 and 1.0 x 10(9) cells/l, were significantly inversely correlated with telomere length of the infused PBPC (r=-0.88, -0.81, -0.77, respectively; P<0.05,). However, no correlation was found for patients who received G-CSF from day 1 post transplantation (n=20). These data suggest that for transplantation with sufficient CD34(+) cells, neutrophil recovery is less efficient in patients receiving infusions of cells with short telomeres, but this deficiency can be corrected with adequate post transplantation administration of G-CSF.Bone Marrow Transplantation (2004) 34, 439-445. doi:10.1038/sj.bmt.1704607 Published online 19 July 2004     

Ideal or actual body weight to calculate CD34+ cell doses for autologous hematopoietic stem cell transplantation?

The number of CD34+ cells infused influences the speed of hematologic recovery post-transplant. There are limited data on whether ideal (IBW) or actual (ABW) body weight should be used to calculate CD34+ cell dose. We compared the correlation between recovery to 0.5 x 10(9)/l neutrophils and the CD34+ cell dose based upon ABW as well as IBW in 87 patients autografted for cancer. ABW was >or=25% over IBW in 43% of patients. The median number of CD34+ cells administered was 3.6 x 10(6)/kg ABW and 4.2 x 10(6)/kg IBW. The time to neutrophil recovery was 8-15 days (median 10). There was a stronger inverse correlation between CD34+ cell dose/IBW and neutrophil recovery (r(2)=0.308; P<0.0001) than between CD34+ cell dose/ABW and neutrophil recovery (r(2)=0.267; P<0.0001). The median time to neutrophil recovery was comparable for those receiving >or=2 x 10(6)/kg CD34+ cells/kg IBW as well as ABW (10 days) and those receiving >or=2 x 10(6)/kg CD34+ cells/kg IBW but <2/kg ABW (10 days), but was significantly slower for those receiving <2 x 10(6)/kg CD34+ cells/kg IBW (12 days). These data show that the CD34+ cell dose based on IBW is a better predictor of neutrophil recovery after autotransplantation.     

Highly fluorescent reticulocyte count predicts haemopoietic recovery after immunosuppression for severe aplastic anaemia

Highly fluorescent reticulocyte (HFR) counts are the most reliable and sensitive index of haemopoietic recovery after bone marrow or peripheral blood stem cell transplantation. We report the behaviour of HFRs during haemopoietic recovery in two patients who were affected by severe aplastic anaemia (SAA) and treated with horse antithymocyte globulin (ATG), cyclosporin A (CsA) and granulocyte colony-stimulating factor (G-CSF). A HFR value > 5% of the total reticulocyte count, a reticulocyte count > 30 x 10(9)/l, and a polymorphonuclear (PMN) count > 0.5 x 10(9)/l were found after 9 and 8, 20 and 46, and 16 and 22 days, respectively, after the end of ATG. HFR recovery to > 5% anticipated the rise of PMN > 0.5 x 10(9)/l by at least 7 and 14 days, respectively. Thus, HFR evaluation could be used as a reliable and early marker of response to immunosuppression in severe aplastic anaemia.