Colony-stimulating factors in the management of neutropenia and its complications

The association of hyperglycemia and diabetes mellitus and the risk of chemotherapy-induced neutropenia among cancer patients: A systematic review with meta-analysis

AIM

Conduct a systematic review with meta-analysis to determine the association between incident chemotherapy-induced neutropenia (CIN) and either diabetes mellitus (DM) or hyperglycemia in patients with cancer.

METHODS

Observational studies in cancer patients of any age receiving chemotherapy and having diabetes or hyperglycemia either during or before chemotherapy induction were included. Studies were retrieved by searching four databases (PubMed, EBSCO, ProQuest, and Cochrane) and cross-referencing. The metric for combining studies was the odds ratio (OR). Results were pooled using a random-effects model, while heterogeneity and inconsistency were assessed using the Q and I2 statistic, respectively. Potential small-study effects were assessed using the funnel plot.

RESULTS

Ten studies met the criteria for inclusion. Overall, the odds of having CIN were 32% higher among cancer patients with either DM or hyperglycemia compared with those without DM or hyperglycemia (OR=1.32, 95% CI, 1.06-1.64). Statistically significant heterogeneity and inconsistency were found (Q=33.15, p<0.05, I2=72.9%). Funnel plot asymmetry reflecting potential small-study effects was observed.

CONCLUSIONS

Diabetes mellitus and hyperglycemia may be associated with an increased risk for CIN among cancer patients. However, additional well-designed studies are needed before any final and definitive recommendations can be made.

Effects of prophylactic hematopoietic colony stimulating factors on stem cell transplantations: meta-analysis

Hematopoietic growth factors are often given for prevention of febrile neutropenia (FN), infections, and other complications by hastening neutrophil recovery in the treatment of malignancies after high dose chemotherapy (HDCT). Although several meta-analyses have already demonstrated beneficial effects of prophylactic granulocyte colony-stimulating factors (G-CSF) administration, the effects of G-CSF have not been confirmed in cancer patients receiving stem cell transplantation (SCT) after HDCT. Therefore, we performed a statistical combination of controlled clinical trials to investigate the efficacy of prophylactic use of G-CSF in preventing the neutropenic complications associated with SCT following HDCT in cancer patients. We searched PubMed to identify potentially relevant references and finally selected seven randomized controlled trials that met all of the eligibility criteria. Our meta-analysis demonstrated that prophylactic G-CSF reduced the risk of documented infections and time to hematologic recovery manifested by days to absolute neutrophil count (ANC) ≥ 0.5 × 10(9)/L, days to ANC ≥ 1.0 × 10(9)/L, and days to platelets ≥ 20 × 10(9)/L in SCT patients with cancer following HDCT. The G-CSF treated group also showed a decrease in the length of hospital stay. However, there was no difference between G-CSF treatment group and placebo group in regard to all-cause mortality, infection-related mortality, grade 2∼4 acute graft-versus-host-disease, and episode of fever.

Visualizing clinical predictors of febrile neutropenia in Asian cancer patients receiving myelosuppressive chemotherapy

PURPOSE

Febrile neutropenia is a serious complication among cancer patients receiving myelosuppressive chemotherapy. Patient-specific risk factors, chemotherapy-related and disease-related characteristics can affect the clinical outcome and management of febrile neutropenia. Although many factors have been identified, they vary among different patient populations. We identified clinically-relevant febrile neutropenia predictors in Asian cancer patients through visualization of these factors.

METHODS

A single-centered, retrospective study was conducted from May to July 2011 at a local cancer center. Demographics and risk factor data were collated from electronic health records and four cancer registries. Data were summarized using descriptive statistics. Additionally, potential febrile neutropenia predictors were identified using categorical principal component and multiple correspondence analyses.

RESULTS

A total of 583 patients were analyzed. Majority was females (79%), Chinese (75%) and diagnosed with breast cancers (60%). Six risk factors were identified as potential predictors: types of cancer (16.9-19.8% of variance), chemotherapy regimen (anthracycline-based 11.8-12.9%, taxane-based 8.1%), liver function tests (alanine transaminase 8.6%, alkaline phosphatase 4.0%), renal function tests (serum creatinine 3.1%), prior granulocyte colony stimulating factor use (5.6%) and diabetes mellitus (6.6-6.9%). In terms of cancer types, lymphomas were more predictive than breast cancers.

CONCLUSION

From our knowledge, this is the first study that has identified clinically-relevant febrile neutropenia predictors in Asian cancer patients through visualization of their risk factors. The use of these predictors to identify patients at risk for adverse reactions, such as FN, can allow clinicians to optimize prophylactic granulocyte colony stimulating factor usage in these patients.

The hematopoietic growth factors in acute leukemia: a European perspective

Acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) are malignant clonal disorders of the blood system requiring intensive and long-term cytotoxic treatment. Current chemotherapy protocols not only target the malignant cell, but are also highly toxic to normal hematopoietic cells as well. Leukemia patients thus experience prolonged times of neutropenia, thrombocytopenia, and anemia, which increase the risk for secondary complications like infections and bleeding. Twenty years ago leukemia patients were considered the ideal candidates to benefit from accelerated recovery of cytopenias by treatment with recombinant cytokines. Moreover, based on in vitro data, it was hypothesized that myeloid growth factors may sensitize AML cells to cytotoxic agents. Numerous clinical trials have documented the biologic activity of granulocyte and granulocyte-macrophage growth factors to accelerate neutrophil recovery after chemotherapy. However, there is high-level evidence that these myeloid growth factors neither reduce the incidence of severe infections nor improve the outcome of AML patients. Evidence from ALL trials is mixed with some studies suggesting a reduction of severe infections by myeloid growth factors whereas others report no effect. Most studies of acute leukemia patients suggested that myeloid growth factors are safe to use, however, a negative impact on event-free survival was found in one trial and an increased risk for secondary AML was reported in pediatric ALL patients. Thrombopoietins have not led so far to a significant increase in platelet numbers in leukemia patients. Chemokine receptor antagonists are now being evaluated in clinical trials for synergistic effects with chemotherapy and will be discussed briefly. Cytokine development mirrors the great advances that have been achieved in the understanding of regulatory mechanisms in hematopoiesis. As this understanding grows, new drugs and new applications will emerge.

Gastrointestinal complications in children with acute myeloid leukemia

Gastrointestinal complications in pediatric acute myeloid leukemia (AML) have not been systematically described in the literature. Our objective was to describe complications related to the small and large bowel in children with AML. Literature searches were conducted of Ovid Medline from 1950 to November 2009 and EMBASE from 1980 to November 2009. We included any study design that described gastrointestinal complications in children and/or adults with AML. Common gastrointestinal complications were typhlitis and enterocolitis. Less common complications included appendicitis, pneumatosis intestinalis, and perianal infections. Both leukemia infiltration and intensive chemotherapy likely play a role in the etiology of these conditions. There is a paucity of carefully conducted studies that describe the natural history of typhlitis and enterocolitis and evidence is needed to help guide the management of gastrointestinal complications. Gastrointestinal complications are relatively common in children with AML. Conduction of carefully performed cohort studies is needed to better understand the spectrum of symptoms and expected consequences of gastrointestinal complications. Randomized trials are required to develop evidence-based guidelines for the management of gastrointestinal complications in pediatric AML.

Current status of growth factors in the treatment of acute myeloid and lymphoblastic leukemia

The safety of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with acute leukemia has been well established in numerous clinical trials. The primary aim of these studies was to determine whether CSFs, when used as adjuncts to intensive chemotherapy, reduced the duration of neutropenia, prevented febrile neutropenia, infections, and hospitalization rates, and improved response and overall outcome in patients with acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL). Despite considerable efforts in divers clinical settings, the potential advantages of hematopoietic growth factors in the management of these leukemias remain inconclusive. In general, individual published trials have shown declines in the incidence and/or duration of neutropenia but have not consistently demonstrated a reduction in the overall frequency of infectious complications or the duration of hospitalization. Most protocols also have failed to show a benefit in terms of disease-free or overall survival. Nevertheless, improvements in "soft" clinical end points, such as incidence of severe infections, may be clinically important and contribute, even if only incrementally, to the patient's quality of life. Selection of those patients likely to benefit from growth factors in a specific clinical setting is a worthwhile endeavour.

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.

Granulocyte and granulocyte macrophage colony-stimulating factors as therapy in human and veterinary medicine

Granulocyte colony-stimulating factors (G-CSFs) and granulocyte macrophage colony-stimulating factors (GM-CSFs) are endogenous cytokines that regulate granulocyte colonies and play a major role in the stimulation of granulopoiesis (neutrophils, basophils and eosinophils) and in the regulation of microbicidal functions. There are numerous pathological conditions in which neutrophils are decreased, the most common being neutropenia associated with cancer chemotherapy, which increases the risk of serious microbial infections developing with the potential for high morbidity and mortality. New methods in molecular biology have led to the identification and cloning of CSF genes and biopharmaceutical production. Since then, CSFs have been widely used for the prevention and treatment of neutropenia associated with cancer chemotherapy, for mobilising haematopoietic cell precursors, and for other neutropenia-related pathologies. This review focuses on the use of CSFs within both human and veterinary medicine. Clinical applications, pharmacology, tolerability and the potential role of these factors in veterinary medicine are considered.

G-CSF in the Prevention of Febrile Neutropenia in Chemotherapy in Breast Cancer Patients

The most common chemotherapeutic agents in the treatment of breast cancer are anthracyclines and taxanes. The major dose-limiting toxicities associated with these agents are myelosuppression and associated febrile neutropenia (FN). FN can significantly impact the ability to deliver full-dose chemotherapy on schedule and as a result may increase the risk of disease recurrence and eventual disease-related mortality. The use of granulocyte colony stimulating factors (G-CSFs) significantly improves the management of FN, both in a therapeutic and in a prophylactic approach. Nevertheless, the high cost of these agents limits their widespread prophylactic use. Therefore, the identification of patients who are at a higher risk of developing FN and who will benefit from the prophylactic use of G-CSFs has become the subject of several clinical and cost-effectiveness studies. Recently, new data have been accumulated concerning the risk of FN in different chemotherapy regimens, and different risk models have been developed to assess the neutropenic risk with all its complications. This article reviews and summarizes cutting-edge, disease-specific data as well as national and international guidelines regarding the use of G-CSFs to prevent chemotherapy-induced FN, with focus on the treatment of breast cancer.

An analysis of current neutropenia therapies, including pegfilgrastim

Currently, 2 granulocyte colony-stimulating factors are available in the United States--filgrastim and pegfilgrastim. In patients receiving chemotherapy for solid tumors, lymphoma, and acute myelogenous leukemia, these agents reduce the duration of severe neutropenia, decrease the incidence of febrile neutropenia, and facilitate on-time delivery of scheduled doses of chemotherapy. In addition, substantial data document the benefits of using these agents in patients undergoing peripheral blood progenitor cell mobilization and in patients who have undergone bone marrow transplantation or peripheral blood progenitor cell transplantation. Recent studies suggest that for all of these indications, the efficacy of pegfilgrastim, the newest agent, is comparable to or greater than that of filgrastim. Like filgrastim, pegfilgrastim is generally well tolerated. An important advantage of pegfilgrastim, however, is its once-per-cycle schedule of administration. Patients and health care providers are likely to prefer the administration schedule of pegfilgrastim to the daily administration schedule required with the use of filgrastim. Furthermore, the more convenient schedule of pegfilgrastim may be associated with greater treatment adherence and increased patient quality of life.