Use of molecularly-cloned haematopoietic growth factors in persons exposed to acute high-dose, high-dose rate whole-body ionizing radiations.

Exposure to acute, high-dose, high dose-rate whole-body ionizing radiations damages the bone marrow resulting in rapid decreases in concentrations of blood cells, especially lymphocytes, granulocytes and platelets with associated risks of infection and bleeding. In several experimental models including non-human primate radiation exposure models giving molecularly cloned haematopoietic growth factor including granulocyte/macrophage colony-stimulating factor (G/M-CSF; sargramostim) and granulocyte colony-stimulating factor (G-CSF; filgrastim and pegylated G-CSF [peg-filgrastim]) accelerates bone marrow recovery and increases survival. Based on these data these molecules are US FDA approved for treating victims of radiation and nuclear incidents, accident and events such as nuclear terrorism and are included in the US National Strategic Stockpile. We discuss the immediate medical response to these events including how to estimate radiation dose and uniformity and which interventions are appropriate in different radiation exposures settings. We also discuss similarities and differences between molecularly cloned haematopoietic growth factors.

Filgrastim, lenograstim and pegfilgrastim in the mobilization of peripheral blood progenitor cells in patients with lymphoproliferative malignancies.

Patients with lymphoproliferative disorders, candidate to autologous stem cell transplantation (ASCT), require mobilization with chemotherapy and granulocyte colony -stimulating factor (G-CSF). This study looked for differences in hematopoietic peripheral stem cells (HPSCs) mobilization in response to the three available G-CSFs, namely lenograstim, filgrastim, and pegfilgrastim. Between 2000 and 2012, 146 patients (66 M and 80 F) who underwent ASCT for multiple myeloma, non-Hodgkin's lymphoma or Hodgkin's lymphoma were studied. All patients received induction therapy and then a mobilization regimen with cyclophosphamide plus lenograstim, or filgrastim, or pegfilgrastim. From days 12 to 14, HPSCs were collected by two to three daily leukaphereses. Our results show that high-dose cyclophosphamide plus lenograstim achieved adequate mobilization and the collection target more quickly and with fewer leukaphereses as compared to filgrastim and pegfilgrastim. No differences between the three regimens were observed regarding toxicity and days to WBC and platelet recovery. Thus, lenograstim may represent the ideal G-CSF for PBSC mobilization in patients with lymphoproliferative diseases. Further studies are needed to confirm these results and better understand the biological bases of these differences.

Growth factor and patient-adapted use of plerixafor is superior to CY and growth factor for autologous hematopoietic stem cells mobilization.

The ideal method to mobilize autologous hematopoietic stem cells (AHSCs) in patients with lymphoma or multiple myeloma remains to be determined. The use of plerixafor, added to growth factor, may overcome the limitations to the use of growth factor mobilization without chemotherapy. We developed and validated a cost-based decision-making algorithm that uses the CD34+ cell count in the peripheral blood on the fourth day of G-CSF administration and the target CD34+ cell count for the specific patient to decide on the use of plerixafor (MUSC algorithm). We compared this approach (MA cohort) with a historical cohort of patients undergoing mobilization with CY 2000 mg/m(2) followed by G-CSF and GM-CSF (CY cohort). Fifty individuals are included in the MA cohort and 81 in the CY cohort. The mobilization failure rate was 2% in the MA cohort vs 22% in the CY cohort (P=0.01). Fewer patients in the MA cohort than in the CY cohort had infectious complications during mobilization requiring hospitalization (2 vs 30% P<0.01). There was significant shortening in the median number of days between starting mobilization and undergoing transplantation in the MA cohort (14 vs 43 days, P<0.01). In conclusion, growth factor and patient-adapted use of plerixafor provides safer hematopoietic stem cell mobilization and faster access to AHSC transplantation.

[Hematopoietic growth factors. Possibilities and limitations]. / Hämatopoetische Wachstumsfaktoren. Möglichkeiten und Grenzen.

The production of hematopoietic cells is under the tight control of distinct growth factors. As therapeutic agents, granulocyte colony-stimulating factor (G-CSF), erythropoietin (EPO), and thrombopoiesis-stimulating agents (TSA) are in routine clinical use. Granulocyte colony-stimulating factor is used to prevent febrile neutropenia or to increase dose-density in chemotherapy regimens. Despite a reduced duration of neutropenia, randomized controlled trials have documented only a modest clinical benefit. A clinical advantage of dose-dense chemotherapy has been shown only in specific chemotherapy regimens. Clinical practice guidelines recommend the use of G-CSF for patients with a high risk of adverse outcome of febrile neutropenia. Erythropoiesis-stimulating agents (ESAs) are used as an alternative to blood transfusion in patients with chemotherapy-induced anemia. However, recent meta-analyses of clinical studies suggest that their use was associated with an increased risk of all-cause mortality and serious adverse events. Thrombopoiesis-stimulating agents have been introduced recently into the market for patients with immune thrombocytopenic purpura. Prior to the use of TSA in other conditions such as chemotherapy-induced thrombocytopenia the lessons learned with G-CSF and ESAs should be taken into account.

Are guidelines on use of colony-stimulating factors in solid cancers flawed?

In cancer care in Australia, we are very reliant on an array of expensive pharmaceuticals. Our use of these treatments is often based on multinational or foreign clinical studies. Oncologists are, to varying degrees, reliant on how the studies are interpreted by the writers of journal editorials, clinical guidelines and opinion pieces. Therefore it is important that these guidelines are balanced and evidence based. We have examined in detail one of the most influential and wide ranging clinical guidelines used in oncology, The American Society of Clinical Oncology (ASCO) 2006 Update of Recommendations for the use of White Blood Cell Factors: An Evidence-Based Clinical Practice Guideline. We have discussed in detail some of the controversial recommendations in this guideline and have exposed what we believe are some flaws in these recommendations. We would urge that we continue to be rigorous in our oversight of international research agendas and international clinical guidelines in the future.

Hematopoietic growth factors in the treatment of acquired bone marrow failure states.

In severe aplastic anemia (SAA), the use of hematopoietic growth factors (HGFs) to support blood counts is of limited value, as predicted by in vitro studies and measurement of endogenous serum levels of hematopoietic growth factors (HGF), which are markedly elevated. Benefit is usually only seen in those with less severe disease who are unlikely to require HGFs in practice. HGFs administered alone play no role in the treatment of SAA. The main indication for using HGFs, most often granulocyte colony-stimulating factor (G-CSF), in SAA has been to determine whether they increase the response rate to immunosuppressive therapy (IST) and improve survival. While earlier neutrophil recovery occurs when G-CSF is administered with IST, studies to date show no significant advantage in hematologic response or overall survival. Conflicting results have been reported concerning whether G-CSF increases the known risk of myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) after IST; follow-up of at least 10 years is required, lacking in many clinical studies reported to date. In MDS, HGFs have been used to counteract the intramedullary apoptosis, which leads to ineffective hematopoiesis. In several uncontrolled and controlled studies, especially in low-risk MDS, high-dose erythropoietin (EPO) or its glycosylated derivative darbepoetin (DPO), alone or in combination with G-CSF, increased hemoglobin levels and diminished the need for red blood cell transfusions, in selected patients with prior transfusion frequency of less than 2 units per month and EPO levels below 500 IU/L. Quality-of-life measures were claimed to have improved, but the cost-effectiveness of this approach is debated, as is safety with regard to the risk of progression. G-CSF is used in supportive care of MDS to improve neutropenia during infectious complications, but to date there is no compelling evidence for a survival benefit or alteration of the course of the disease through the use of HGFs in MDS.

Increasing chemotherapy in small-cell lung cancer: from dose intensity and density to megadoses.

The hypothesis that increasing cytotoxic dose intensity will improve cancer cure rates is compelling. Although supporting evidence for this hypothesis has accrued for several tumor types, including lymphomas, breast cancer, and testicular cancers, it remains unproven. Small-cell lung cancer is extremely chemo- and radiosensitive, with a response rate of 80% achieved routinely, but few patients are cured by chemoradiotherapy. In this setting, increased cytotoxic dose intensity might improve cure rates. The finding that response rates in small-cell lung cancer correlate with received cytotoxic dose intensity merely confirms that "less is worse" and "more is better." Within conventional ranges, dose intensity can be increased with the support of hematopoietic growth factors and/or by shortening treatments intervals; however, dose intensity could be increased by only 20%-30%, and a survival advantage has not been clearly demonstrated. Given its high chemosensitivity, small-cell lung cancer was one of the first malignancies deemed suitable for increasing dose intensity and even for the use of a megadose with the support of autologous bone marrow transplantation. Some interest is emerging again due to improvements in supportive care, such as the availability of hematopoietic growth factors and peripheral blood progenitor cells.

Dose-dense chemotherapy for primary breast cancer.

PURPOSE OF REVIEW: Dose density is a relative term referring to the administration frequency of chemotherapy drugs and regimens compared with standard regimens. The concept of dose-dense chemotherapy is based on the hypothesis that maximal chemotherapy effectiveness can be achieved by scheduling the interval of chemotherapy to correspond to the period of most rapid tumor growth. The present paper aims to outline the theoretical framework for dose-dense chemotherapy and to review recent clinical trials addressing this concept within adjuvant breast cancer treatment. RECENT FINDINGS: Several randomized trials have been conducted to test the feasibility and effectiveness of anthracycline and/or taxanes-based dose-dense strategies. They demonstrate that using hematopoietic growth factor support has made dose-dense therapy safe and feasible. Dose-dense strategies have been associated with a modest impact on disease recurrence and overall survival of patients with early-stage breast cancer. Subset analyses suggest increased benefits for specific tumor subtypes such as hormone receptor-negative, highly proliferative or HER2 overexpressing tumors. SUMMARY: Trials in unselected patients with early-stage breast cancer have demonstrated promising results for dose-dense chemotherapy. Further studies are needed to define the optimal regimen and the patient population that will receive the greatest benefit from this therapy.

Administration of hematopoietic cytokines in the subacute phase after cerebral infarction is effective for functional recovery facilitating proliferation of intrinsic neural stem/progenitor cells and transition of bone marrow-derived neuronal cells.

BACKGROUND: Hematopoietic cytokines, granulocyte colony-stimulating factor (G-CSF), and stem cell factor (SCF) were reported to show a neuroprotective effect or to support neurogenesis. These cytokines also mobilize bone marrow (BM) cells into the brain, and the BM-derived cells differentiate into neuronal cells. We administered these hematopoietic cytokines after focal cerebral ischemia and assessed their effects and the therapeutic time window for neuronal regeneration. METHODS AND RESULTS: We induced permanent middle cerebral artery occlusion in mice whose BM had been replaced with BM cells from green fluorescent protein (GFP)-transgenic mice. The occluded mice were treated with G-CSF and SCF in the acute phase (days 1 to 10) or subacute phase (days 11 to 20), and the brain functions and histological changes were evaluated. Separately, we injected bromodeoxyuridine during cytokine treatment to assess cell kinetics in the brain. Six mice were prepared for each experimental group. Administration of G-CSF and SCF in the subacute phase effectively improved not only motor performance but also higher brain function, compared with acute-phase treatment. Acute-phase and subacute-phase treatments identically reduced the infarct volume relative to vehicle treatment. However, subacute-phase treatment significantly induced transition of BM-derived neuronal cells into the peri-infarct area and stimulated proliferation of intrinsic neural stem/progenitor cells in the neuroproliferative zone. CONCLUSIONS: Administration of G-CSF and SCF in the subacute phase after focal cerebral ischemia is effective for functional recovery, enhancing cytokine-induced generation of neuronal cells from both BM-derived cells and intrinsic neural stem/progenitor cells. Because G-CSF and SCF are available for clinical use, these findings suggest a new therapeutic strategy for stroke.

Bone marrow transplantation in adults with thalassemia: Treatment and long-term follow-up.

Current regular blood transfusion programs and chelation treatment have considerably improved survival of patients with thalassemia, which resulted in a larger proportion of adult patients. However, disease- and treatment-related complications in these patients progress over time, causing severe morbidity and shortened life expectancy. Stem cell transplantation still remains the only cure currently available for patients with thalassemia. This study updates transplant outcomes in 107 adult patients with median age of 22 years (range, 17-35 years) who received bone marrow transplantation (BMT) from human leukocyte antigen (HLA)-identical related donors between 1988 and 1996 (group A) and describes the results of BMT in 15 adult patients with median age of 21 years (range, 17-31 years) who were treated with a new treatment protocol (Protocol 26) between 1997 and 2003 (group B). The probability of survival, event-free survival, nonrejection mortality, and rejection for group A patients were 66%, 62%, 37%, and 4%, respectively, with a median follow-up of 12 years (range, 8.3-16.2 years). Group B patients treated with the new protocol had some improvement in thalassemia-free survival (67%) and lower transplant-related mortality (27%) than that of previous protocols. However, transplant-related mortality in these high-risk patients remains elevated. Current myeloablative BMT in adult patients is characterized by higher transplant-related toxicity due to an advanced phase of disease. Although this new approach to transplant adult patients with a reduced-dose intensity-conditioning regimen has improved thalassemia-free survival, transplant-related mortality in these high-risk patients remains elevated.

Dendritic cell-based immunotherapy of malignant gliomas.

The failure of conventional treatment modalities for gliomas, in spite of tremendous progress in research in the past two decades, has led to increasing interest in alternative treatment strategies, including immunotherapy. It has become evident that vaccination with dendritic cells (DC), designed to express tumor antigens, is a potent strategy to elicit anti-tumor immune response in both pre-clinical and clinical settings. Various methods have been applied in order to induce DC to express tumor antigens including: pulsing with isolated tumor peptides or whole tumor lysate; fusion with tumor cells; and pulsing with apoptotic tumor cells. Herein, we review the recent progress in DC biology with regard to tumor immunity and discuss current DC-based strategies and future prospects in immunotherapy for malignant gliomas.

Supportive treatment for anemic cancer patients.

Anemia in cancer patients is frequent but often underestimated. Anemia affects the health-related quality of life and impacts prognosis and outcome of therapy. Treatment options include the administration of hematopoietic growth factors and red blood cell transfusions. Blood transfusions result in rapid but often transient improvement of anemia. Administration of epoetin or darbepoetin alfa increases hemoglobin levels, decreases blood transfusions, and improves quality of life in patients with cancer. Presently, trials investigate whether treatment of anemic cancer patients with erythropoietin impacts on outcome of chemo- and/or radiotherapy and on overall survival. Oncologists must be aware of the clinical relevance of anemia and offer adequate treatment options to their patients. Supportive treatment of anemic cancer patients presenting anemia-related symptoms should be performed to reduce symptoms in cancer patients and optimize outcome to anticancer therapy.

Hematopoietic growth factors in neonatal medicine: the use of enterally administered hematopoietic growth factors in the neonatal intensive care unit.

The practice of complete bowel rest in prematurely delivered neonates and those who have undergone surgery for congenital anomalies of the gastrointestinal (GI) tract is common in neonatal intensive care units (NICU). However, increased recognition of the critical role of growth factors in GI development suggests that this practice might be modified to include the administration of synthetic amniotic fluid-like solutions designed to bridge the neonate between their intra-uterine environment and that of the NICU. This article reviews advances in administering synthetic amniotic fluid-like solutions in the NICU.

Hematopoietic growth factors in myelodysplastic syndromes.

The myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic stem cell disorders characterized clinically by refractory cytopenias in one or more myeloid cell lines and an increased probability of transformation to acute leukemia. Supportive care remains the mainstay of therapy in MDS and frequently includes monotherapy and combination therapy with hematopoietic growth factors, such as erythropoietin, granulocyte colony-stimulating factor, and granulocyte macrophage colony-stimulating factor. Clinical trials have demonstrated the ability of growth factors to improve neutropenia and anemia in selected patients with MDS, which may have clinical, quality-of-life, and economic benefits for patients even though overall survival has not been improved. This paper reviews the role of hematopoietic growth factors in the treatment of MDS.

Impact of chemotherapy regimen and hematopoietic growth factor on mobilization and collection of peripheral blood stem cells in cancer patients.

Various chemotherapy regimens, combined with recombinant human granulocyte colony-stimulating factor(rhG-CSF) or recombinant granulocyte-macrophage CSF (rhGM-CSF) are used in cancer patients to mobilize and collect peripheral blood stem cells (PBSC). In this retrospective study, we evaluated and compared the efficacy of such regimens in 262 patients with different types of malignant diseases. The following chemotherapy regimens were applied: ifosfamide-etoposide-cisplatin or bleomycin (n = 96; mainly patients with testicular cancer); ifosfamide-etoposide plus or minus cytosine arabinoside (Ara-C) or vincristine (VCR)(n = 52; mainly patients with lymphoma); cyclophosphamide-anthracycline (n = 53; mainly patients with breast cancer); intermediate to high dose (ID-HD) cyclophosphamide (n = 37; mainly patients with breast or ovarian cancer. or multiple myeloma; and others (n = 24). rhG-CSF or rhGM-CSF, each at an average daily dose of 5 microg/kg body weight, were used in 166 and 96 patients, respectively. The study evaluated and compared the efficacy of these two cytokines. In patients receiving rhG-CSF, CD34+ cells could be collected earlier (median: day 14 versus day 16) and there was a significantly higher white blood cell count (WBC)(median 11,350 versus 5550/microl) and CD34+ cell count (median 88 versus 43/microl) at the start of apheresis, and a significantly higher CD34+ cell yield (median 7.4 x 10(6) versus 4.6 x 10(6)/kg) than in patients who receivedrhGM-CSF. Among the various chemotherapeutic regimens used, each combined with rhG-CSF, ifosfamide-etoposide plus or minus Ara-C or VCR mobilized a significantly higher number of CD34+ cells (median 119/microl) and produced a significantly higher harvest of these cells (median 13 x 10(6)/kg) than cyclophosphamide-anthracycline (median 87/microl and 7 x 10(6)/kg, respectively) or ID-HD cyclophosphamide (median 59/microl and 5 x I 0(6)/kg, respectively). Ifosfamide-etoposide plus or minus Ara-C or VCR was also superior to ifosfamide-etoposide-cisplatin or bleomycin (median 78/microl and 9 x 10(6)/kg, respectively), but at borderline significance. The outcome of PBSC mobilization and collection appeared to be negatively influenced by the number of relapses before the current salvage treatment. These data indicate that mobilization and collection of PBSCstrongly depend on the type of hematopoietic growth factor and chemotherapeutic regimen used. The data further show rhG-CSF is a more effective growth factor than rhGM-CSF and ifosfamide-etoposide-based regimens, particularly ifosfamide-etoposide plus or minus Ara-C or VCR, are highly effective regimens in mobilizing and collecting CD34+ cells.

Enteral administration of hematopoietic growth factors in the neonatal intensive care unit.

UNLABELLED: By 20 wk of gestation, the human fetal gastrointestinal (GI) tract morphologically resembles that of the term infant, but functional development is limited before 26 wk. By 30 wk of gestation, the fetus has the capacity for limited digestion and enteral absorption. GI growth and development continue postnatally. Trophic factors, including nutrients, peptides, hormones and growth factors, are recognized as having important influences on the morphology and histology of the developing GI tract. Other trophic factors are important in adaptation and repair following injury. Many such factors are provided in utero via amniotic fluid swallowing and later by human colostrum and milk. CONCLUSION: This review discusses cytokines with known GI trophic effects, either in vitro or in vivo, and focuses on those cytokines that have been used in the neonatal intensive care unit.

Rescue of haemopoiesis by a combination of growth factors including stem-cell factor.

We observed an unexpectedly rapid rise in platelet counts with complete haematological recovery after a BEAM regimen, in a patient who could not be rescued by autologous transplant but who received filgrastim, epoetin alfa, and ancestim. We feel that these results may be attributed to this specific growth factor combination, including ancestim, a cytokine known to act on primitive stem cells. If confirmed, this observation may open new possibilities in intensive chemotherapy for patients for whom haematopoietic progenitors are difficult to harvest. This may also represent an alternative to ex-vivo expansion and deserves further investigation.

Growth factor practice patterns among pediatric oncologists: results of a 1998 Pediatric Oncology Group Survey. Economic Evaluation Working Group the Pediatric Oncology Group.

The American Society of Clinical Oncology (ASCO) guidelines on growth factor (GF) use recommend applying adult-derived guidelines in pediatric oncology. An ASCO survey of adult oncology GF use determined the preference for first degree prophylaxis (use of GF when febrile neutropenia [FN] is expected to be high in untreated patients), second-degree prophylaxis (administration of GF after a documented episode of FN on a previous cycle of chemotherapy), and intervention in the treatment of FN. Similar preferences have not been evaluated in pediatrics. The purpose of this study was to (1) characterize GF use in pediatric oncology; (2) correlate use patterns with demographic factors; and (3) compare the Pediatric Oncology Group (POG) and ASCO surveys. The ASCO survey was revised for use within pediatric oncology and was mailed to the physician membership of POG; 341 were returned (86% completion rate). Comparisons were made with the ASCO survey. Most (76%) physicians said GF use was determined by protocol requirements and most (70%) patients were entered on POG protocols. GF use as first-degree prophylaxis was selected 40% of the time, which was significantly greater than in adults; this was most influenced by anticipated duration of neutropenia (> or =7 days). The severity of the initial clinical course (e.g., neutropenia, infection) influenced use in second-degree prophylaxis; dose reduction alone was never selected. For FN, GF use was 45%, with lower preferences in uncomplicated FN (16%-38%) compared with complicated FN (66%). POG respondents endorse greater use of GF for first-and second-degree prophylaxis but less use in uncomplicated FN than do ASCO respondents. These patterns may reflect different strategies, including the role of chemotherapy, value of dose intensity, and perceived toxicity of regimens. Given these differences, adult-based guidelines may not be appropriate for pediatrics.