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David C Dale

Publications and source records attributed to David C Dale.

At least 37 records · Page 2Linked to original sources
PubMed2004

Chemotherapy-induced neutropenia: risks, consequences, and new directions for its management.

Cytotoxic chemotherapy suppresses the hematopoietic system, impairing host protective mechanisms and limiting the doses of chemotherapy that can be tolerated. Neutropenia, the most serious hematologic toxicity, is associated with the risk of life-threatening infections as well as chemotherapy dose reductions and delays that may compromise treatment outcomes. The authors reviewed the recent literature to provide an update on research in chemotherapy-induced neutropenia and its complications and impact, and they discuss the implications of this work for improving the management of patients with cancer who are treated with myelosuppressive chemotherapy. Despite its importance as the primary dose-limiting toxicity of chemotherapy, much concerning neutropenia and its consequences and impact remains unknown. Recent surveys indicate that neutropenia remains a prevalent problem associated with substantial morbidity, mortality, and costs. Much research has sought to identify risk factors that may predispose patients to neutropenic complications, including febrile neutropenia, in an effort to predict better which patients are at risk and to use preventive strategies, such as prophylactic colony-stimulating factors, more cost-effectively. Neutropenic complications associated with myelosuppressive chemotherapy are a significant cause of morbidity and mortality, possibly compromised treatment outcomes, and excess healthcare costs. Research in quantifying the risk of neutropenic complications may make it possible in the near future to target patients at greater risk with appropriate preventive strategies, thereby maximizing the benefits and minimizing the costs.

Aged↗
PubMed2003

Incidence and predictors of low dose-intensity in adjuvant breast cancer chemotherapy: a nationwide study of community practices.

PURPOSE: This retrospective study was undertaken to assess practice patterns in adjuvant chemotherapy for early-stage breast cancer (ESBC) and to define the incidence and predictive factors of reduced relative dose-intensity (RDI). PATIENTS AND METHODS: A nationwide survey of 1,243 community oncology practices was conducted, with data extracted from records of 20,799 ESBC patients treated with adjuvant chemotherapy. Assessments included demographic and clinical characteristics, chemotherapy dose modifications, incidence of febrile neutropenia, and patterns of use of colony-stimulating factor (CSF). Dose-intensity was compared with published reference standard regimens. RESULTS: Dose reductions > or =15% occurred in 36.5% of patients, and there were treatment delays > or =7 days in 24.9% of patients, resulting in 55.5% of patients receiving RDI less than 85%. Nearly two thirds of patients received RDI less than 85% when adjusted for differences in regimen dose-intensity. Multivariate analysis identified several independent predictors for reduced RDI, including increased age; chemotherapy with cyclophosphamide, methotrexate, and fluorouracil, or cyclophosphamide, doxorubicin, and fluorouracil; a 28-day schedule; body-surface area greater than 2 m2; and no primary CSF prophylaxis. CSF was often initiated late in the chemotherapy cycle. CONCLUSION: Patients with ESBC are at substantial risk for reduced RDI when treated with adjuvant chemotherapy. Patients at greatest risk include older patients, overweight patients, and those receiving three-drug combinations or 28-day schedules. Predictive models based on such risk factors should enable the selective application of supportive measures in an effort to deliver full dose-intensity chemotherapy.

Adolescent↗
PubMed2003

Mobilization of hematopoietic progenitor cells in healthy volunteers by AMD3100, a CXCR4 antagonist.

Stromal cell-derived factor 1 (SDF1/CXCL12) and its cognate receptor, CXCR4, play key regulatory roles in CD34+ cell trafficking. We investigated whether AMD3100, a selective CXCR4 antagonist, could mobilize hematopoietic progenitor cells from marrow to peripheral blood in healthy human volunteers. Initially, 10 persons each received a single dose of AMD3100 (80 microsubcutaneously), which induced rapid, generalized leukocytosis associated with an increase in peripheral blood CD34+ cells, representing pluripotent hematopoietic progenitors by in vitro colony-forming unit assays, from 3.8 +/- 0.5/microL to 20.7 +/- 3.5/microL at 6 hours. Subsequent dose-response studies showed a maximum increase in circulating CD34+ cells from 2.6 +/- 0.3/microL to 40.4 +/- 3.4/microL at 9 hours after 240 micro/kg AMD3100. Serial administration of AMD3100 (80 microg/kg/d for 3 days) resulted in consistent, reversible increases in peripheral blood CD34+ cells. AMD3100 was well tolerated and caused only mild, transient toxicity. These findings suggest potential clinical application of AMD3100 for CD34+ cell mobilization and collection for hematopoietic stem cell transplantation.

Adult↗
PubMed2003

Treatment of canine cyclic neutropenia by lentivirus-mediated G-CSF delivery.

Cyclic neutropenia is a rare disease that occurs both in humans and gray collie dogs and is characterized by recurrent severe neutropenia leading to bacterial infections and shortened life expectancy. Daily injections of recombinant granulocyte colony-stimulating factor (rG-CSF) are effective in shortening the period of severe neutropenia and reducing infections. After demonstrating that rG-CSF induced elevated neutrophil production in an affected dog, cytokine administration was stopped and 109 infectious units (IUs) of a lentivirus pseudotyped with vesicular stomatitis virus G protein (VSV-G) encoding canine G-CSF cDNA was administered intramuscularly. Serial blood cell counts showed elevated neutrophil production for longer than 17 months. Although neutrophil counts continued to cycle, the range at nadirs was from 3710 to 5300 cells/microL, well above the nadirs before lentivirus administration. After the injection of lentivirus, mean neutrophil counts +/- SD were 12 460 +/- 4240 cells/microL, significantly increased over both pretreatment values of 3040 +/- 2540 cells/microL(P <.0001) and neutrophil counts during G-CSF administration of 10 290 +/- 4860 cells/microL(P <.007). The changes in blood counts from lentivirus injection were associated with absence of clinical signs of infection and fever. The gray collie continued to gain weight and was no longer housed in a pathogen-free environment. Genomic DNA from muscle at injection sites was positive for provirus, whereas gonad, lung, spleen, heart, liver, kidney, leukocytes, and noninjected muscle samples were all negative for provirus. Thus, intramuscular administration of lentivirus encoding G-CSF provided sustained therapeutic levels of neutrophils, suggesting this approach may be applied for long-term treatment of patients with cyclic and other neutropenias.

Animals↗
PubMed2003

Severe chronic neutropenia: treatment and follow-up of patients in the Severe Chronic Neutropenia International Registry.

Severe chronic neutropenia (SCN) is defined as an absolute neutrophil (ANC) of less than 0.5 x 10(9)/L, lasting for months or years. Congenital, cyclic, and idiopathic neutropenia are principal categories of SCN. Since 1994, the Severe Chronic Neutropenia International Registry (SCNIR) has collected data to monitor the clinical course, treatments, and disease outcomes for SCN patients. This report summarizes data for 853 patients, almost all treated with daily or alternate-day recombinant human granulocyte colony-stimulating factor (G-CSF or Filgrastim). G-CSF treatment increased the ANC overall from 0.34 x 10(9)/L +/- 0.018 pre-treatment to 3.70 x 10(9)/L +/- 0.18 during the first year of treatment. For most patients, the responses were durable with patients remaining on the same dose of G-CSF for many years. Long-term hematological observations showed stable mean leukocyte and neutrophil counts and gradually increasing hemoglobin levels. Thrombocytopenia developed in 4% of patients. As of January 1, 2000, myelodysplasia (MDS) or acute myelogenous leukemia (AML) has occurred in 35 of 387 patients with congenital neutropenia with a cumulative risk of 13% after 8 years of G-CSF treatment. This event occurred without a predictable relationship to the duration or dose of G-CSF treatment. No patients with cyclic or idiopathic neutropenia developed MDS or AML. Other important adverse events included hepatomegaly, osteoporosis, vasculitis, glomerulonephritis, and deaths in 4 of 14 cases requiring splenectomy. Growth and development and the outcome of pregnancy appeared to be unaffected by G-CSF treatment. These data indicate that congenital, cyclic, and idiopathic neutropenia can be effectively treated with long-term G-CSF. The risk of leukemia, osteoporosis, other potentially adverse events, and pregnancy outcome need to be further evaluated with continuing long-term observations.

Adolescent↗
PubMed2003

Molecular basis and therapy of disorders associated with chronic neutropenia.

There have been many recent advances in our understanding of the molecular basis of neutropenia disorders, primarily through advances in genetic analysis of inherited disorders. Molecular and cellular studies now suggest that accelerated apoptosis of neutrophil precursors in the bone marrow is the common pathophysiologic mechanism. Severe congenital neutropenia and cyclic neutropenia, both usually inherited as autosomal-dominant disorders, are caused by mutations in the neutrophil elastase gene. Myelokathexis is attributed to the downregulation of the bcl-x protein, but the genetic basis is not yet known. The genes for several diseases with more complex phenotypes (eg, glycogen storage disease type 1b, Chediak-Higashi syndrome, Shwachman-Diamond syndrome, dyskeratosis congenita, Griscelli syndrome, Barth syndrome, and Wiskott-Aldrich syndrome) have all been identified recently. The molecular mechanisms for most acquired disorders causing neutropenia (eg, idiopathic neutropenia, pure white-cell aplasia, myelodysplasia, and aplastic anemia) are not yet known. Granulocyte colony stimulating factor (G-CSF) is effective treatment for several of these conditions. Through better understanding of these disorders, we anticipate that better treatments will be found in the future.

Bone Marrow↗
PubMed2003

Cellular and molecular abnormalities in severe congenital neutropenia predisposing to leukemia.

Severe congenital neutropenia (SCN) is a rare hematological disease characterized by a selective decrease in the level of circulating neutrophils in peripheral blood, maturation arrest at the promyelocyte stage of differentiation in the bone marrow, recurrent severe infections, and evolution to acute myelogenous leukemia (AML). Cellular and molecular studies of 12 SCN patients, including 5 patients that evolved to develop AML, revealed impaired proliferative characteristics and accelerated apoptosis of bone marrow progenitor cells in SCN compared with 11 healthy controls as demonstrated by flow cytometry analysis. Sequencing analysis revealed heterozygous deletion or substitution mutations in the neutrophil elastase (NE) gene in 9 of 12 patients but not in healthy controls. Expression of various NE mutants, but not normal NE, resulted in accelerated apoptosis of human promyelocytic HL-60 progenitor cells, similar to impaired survival observed in patients' cells. Bone marrow-derived primitive CD34(+) and CD33(+)/CD34(-) progenitor cells from SCN patients evolving to AML, all with mutations in the granulocyte colony-stimulating factor receptor (G-CSFR) gene, demonstrated normal cell survival, whereas more differentiated CD15(+)/CD33(-)/CD34(-) cells negative for mutant G-CSFR gene, continue to exhibit accelerated apoptosis. These data demonstrate that impaired survival of bone marrow myeloid progenitor cells, probably driven by expression of mutant NE, is the cellular mechanism responsible for neutropenia in SCN. Furthermore, our results suggest that acquired G-CSFR mutations may initiate signaling events that override the pro-apoptotic effect of mutant NE in primitive progenitor cells, resulting in an expansion of the abnormal AML clone.

Antigens, CD34↗
PubMed2003

Risk of febrile neutropenia among patients with intermediate-grade non-Hodgkin's lymphoma receiving CHOP chemotherapy.

We sought to identify risk factors associated with the time to febrile neutropenia in patients with intermediate-grade, non-Hodgkin's lymphoma (NHL) who were receiving treatment with CHOP chemotherapy. Data were collected from 12 community and academic oncology practices participating in the Oncology Practice Pattern Study between 1991 and 1999. We reviewed the medical records of 577 intermediate-grade NHL patients who received initial CHOP chemotherapy and evaluated risk factors associated with time to first febrile neutropenic event. A febrile neutropenic event was defined as a body temperature of > 100.6 degrees F and an ANC nadir < 1000/mm3. A total of 160 patients experienced 224 febrile neutropenic events. The risk of febrile neutropenia was significantly associated with age > or = 65 years (p = 0.001), cardiovascular disease (p = 0.020), renal disease (p = 0.006), baseline hemoglobin < 12 g/dl (p = 0.018), > 80% planned average relative dose intensity (ARDI; p = 0.018), and no prophylactic colony-stimulating factor (CSF) use (p = 0.046). First febrile neutropenic events occurred by day 14 of cycle 1 in one-half of patients experiencing febrile neutropenia. In multivariate analysis, the risk of febrile neutropenia remained significantly associated with age > or = 65 years (HR = 1.65, 95% CI: 1.18-2.32), renal disease (HR = 1.91. 95% CI: 1.10-3.30), cardiovascular disease (HR = 1.54, 95% CI: 1.02-2.33), baseline hemoglobin < 12 g/dl (HR = 1.44, 95% CI: 1.04-2.00), > 80% planned CHOP ARDI (HR = 2.41, 95% CI: 1.30-4.47), and no CSF prophylaxis (HR = 2.13, 95% CI: 1.20-3.76). Such a model may permit the identification of patients at greatest risk of febrile neutropenia and, therefore, candidates for the selective prophylactic use of the hematopoietic growth factors.

Adult↗
PubMed2003

Optimizing the management of chemotherapy-induced neutropenia.

Chemotherapy-induced neutropenia (CIN), the most common dose-limiting toxicity of cancer chemotherapy, is associated with numerous clinical, personal, and economic consequences. The principal strategies for managing CIN are reducing the dose intensity of the chemotherapy, using antibiotics, and using colony-stimulating factors (CSFs). Reducing or delaying the chemotherapy dose is effective, but this can compromise treatment outcomes. Antibiotics can be lifesaving, but they are associated with numerous adverse effects and the emergence of resistant pathogens. The granulocyte CSF (G-CSF) filgrastim can reduce the incidence, duration, and severity of CIN, as well as the risk of infection, in patients treated with myelosuppressive chemotherapy. The availability of pegfilgrastim, a sustained-duration G-CSF that has benefits comparable to those of filgrastim with a single injection per chemotherapy cycle, has simplified CSF therapy.

Antineoplastic Agents↗
PubMed2002

Therapeutic use of cytokines to modulate phagocyte function for the treatment of infectious diseases: current status of granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor, and interferon-gamma.

The innate immune system represents the initial arm of host defense against pathogenic bacteria, fungi, and parasites. Neutrophils, monocytes, and tissue-based macrophages are major cellular components of this system. The potential ability to augment activity of the innate immune system has increased dramatically during the past 2 decades, with the discovery and development of cytokines. Four cytokines, namely granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor (M-CSF), and interferon (IFN)-gamma, have received increasing attention as potential adjunctive agents for the treatment of infectious diseases. In various animal models of infection, therapeutic administration of each of the 4 cytokines has been shown to enhance pathogen eradication and to decrease morbidity and/or mortality. However, variable therapeutic efficacy has been reported in clinical trials conducted to date. This review summarizes the current status of the use of G-CSF, GM-CSF, M-CSF, and IFN-gamma in the treatment of infectious diseases.

Animals↗
PubMed2002

Granulocyte transfusion therapy for infections in candidates and recipients of HPC transplantation: a comparative analysis of feasibility and outcome for community donors versus related donors.

BACKGROUND: Feasibility, response to granulocyte transfusion therapy, and clinical outcome were compared among HPC transplant recipients enrolled in a prospective study of a community blood bank-based unrelated donors program, a prospective granulocyte study using family donors, and matched control patients without granulocyte transfusion therapy. STUDY DESIGN AND METHODS: Overall, 40 patients (327 collections) received granulocyte concentrates from unrelated donors, 34 patients (219 collections) received granulocyte concentrates from related donors, and 74 patients served as controls. Study entry criteria for patients included an absolute neutrophil count (ANC) of less than 200 per microL and documented invasive fungal or bacterial infections. RESULTS: There was a median delay of 3 days (range, 0-14) in patients receiving transfusions from unrelated donors between day of diagnosis of infection and start of granulocyte transfusion therapy as compared with a median delay of 5 days (range, 0-25) in patients receiving transfusions from related donors (p = 0.01). The ANC increment after the first, second, and seventh transfusions in patients who had community donors was significantly higher or comparable to patients who had family donors. Overall, clinical outcome was comparable between the three patient groups. Kaplan-Meier analysis revealed no difference between all cohorts in overall 6-month survival (p = 0.28, log-rank) or event-free survival (p = 0.17, log-rank). CONCLUSION: These results suggest that future efficacy trials should consider inclusion of unrelated community donors for timely institution of granulocyte transfusion therapy.

Adolescent↗
PubMed2002

Neutropenia: causes and consequences.

Neutrophils play a critical role in the acute inflammatory response and host-defenses against bacterial infections. Neutropenia, a deficiency of these cells, predisposes to infection, chiefly by organisms resident on body surfaces. The risk of infection is greatest with severe neutropenia, defined by an absolute blood neutrophil count (ANC) less than 0.5 x 10(9)/L. Severe chronic neutropenia, lasting for more than a few weeks, can be caused by congenital marrow defects, as well as intrinsic and acquired disorders. Evaluation of patients begins with confirmation of neutropenia and examination of a blood smear. A careful review of the patient's medical history, family history, and physical examination is extremely important. Most severely neutropenic patients have a history of oral ulcers and inflammation and recurrent skin infections. Examination of a bone marrow aspirate and/or biopsy and cytogenetic testing are primary for diagnostic evaluation.

Diagnostic Techniques and Procedures↗
PubMed2002

Cyclic neutropenia.

Cyclic neutropenia is a rare hematologic disorder, characterized by repetitive episodes of fever, mouth ulcers, and infections attributable to recurrent severe neutropenia. Fluctuations in blood cells are due to oscillatory production of cells by the bone marrow. Recent genetic, molecular, and cellular studies have shown that autosomal-dominant cyclic neutropenia and sporadic cases of this disease are due to a mutation in the gene for neutrophil elastase (ELA2), located at 19p13.3. This enzyme is synthesized in neutrophil precursors early in the process of primary granule formation. It is currently presumed that the mutant neutrophil elastase functions aberrantly within the cells to accelerate apoptosis of the precursors, resulting in effective and oscillatory production. Cyclic neutropenia is effectively treated with granulocyte colony-stimulating factor (G-CSF), usually at doses of 1 to 5 microg/kg/d (median dose, 2.5 microg/kg/d). Long-term, daily, or alternate-day administration reduces fever, mouth ulcers, and other inflammatory events associated with this disorder. Leukemic transformation is not a recognized risk for cyclic neutropenia, with or without treatment with G-CSF.

Granulocyte Colony-Stimulating Factor↗
PubMed2002

Cloning and sequencing of the canine neutrophil elastase cDNA.

Human cyclic neutropenia, also referred to as cyclic hematopoiesis, is a rare disease characterized by periodic fluctuations in blood cell production by the bone marrow and a corresponding recurrent severe neutropenia every 19-21 days. This results in bacterial infections and shortened life expectancy. Platelets, monocytes, lymphocytes, and reticulocytes cycle with the same periodicity. It has been determined that the neutrophil elastase (NE) gene is mutated in all cases of human cyclic hematopoiesis. Currently, the only animal model for this disease is the grey collie dog, in which there is a strikingly similar periodic neutropenia every 12-14 days. Towards the validation of this animal model, we have cloned and sequenced the canine NE cDNA from a normal dog.

Amino Acid Sequence↗
PubMed2002

Mutant elastase in pathogenesis of cyclic and severe congenital neutropenia.

Severe neutropenia is characterized by maturation arrest of myeloid cells at the promyelocyte stage of hematopoiesis. We reported that accelerated apoptosis of bone marrow myeloid progenitor cells was observed in both cyclic (CN) and severe congenital neutropenia (SCN). Short and long-term cultures of bone marrow CD34+ cells revealed reduced production of multipotent progenitors in SCN. In contrast, production of these cells was slightly elevated in CN compared with CD34+ cells from healthy volunteers. Production of myeloid-committed progenitor cells was significantly reduced in both CN and SCN. FACS analysis of CD34+ cells revealed G /G cell cycle arrest in SCN but not in CN.(0) (1) All CN patients and more than 90% of SCN patients have mutation in the neutrophil elastase (NE) gene. Molecular modeling of NE tertiary structure indicates that mutations observed in SCN are primarily located around the glycosylation sites, whereas CN mutations affect predominantly the active site. Transient expression of CN- or SCN-specific mutant NE cDNA results in impaired survival of human myeloid progenitor cells compared with control cells transfected with intact NE cDNA. We hypothesize that abnormal processing and subcellular localization of mutant NE might predetermine the etiology of cyclic or severe congenital neutropenia.

Hematopoiesis↗
PubMed2002

Colony-stimulating factors for the management of neutropenia in cancer patients.

Neutropenia and its subsequent infectious complications represent the most common dose-limiting toxicity of cancer chemotherapy. Febrile neutropenia (FN) occurs with common chemotherapy regimens in 25 to 40% of treatment-naive patients, and its severity depends on the dose intensity of the chemotherapy regimen, the patient's prior history of either radiation therapy or use of cytotoxic treatment, and comorbidities. The occurrence of FN often causes subsequent chemotherapy delays or dose reductions. It may also lengthen hospital stay, increase monitoring, diagnostic and treatment costs, and reduce patient quality of life. A decade after their introduction, colony-stimulating factors (CSFs) such as granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are now an integral part of the prevention of potentially life-threatening FN; however, only G-CSF has US Food and Drug Administration approval for use in chemotherapy-induced neutropenia. These adjunctive agents accelerate formation of neutrophils from committed progenitors, thereby reducing the duration and severity of neutropenia. Important uses of CSFs in oncology are prevention of FN after chemotherapy, treatment of febrile neutropenic episodes and support following bone marrow transplantation, and collection of CSF-mobilised peripheral blood progenitor cells. G-CSF is used more frequently than GM-CSF for all of these indications because of fewer associated adverse effects. Clinical trials to date have not demonstrated a significant effect on overall survival or disease-free survival, which is most likely to be due to small sample size and lack of power to prove effect. However, they have demonstrated clinical utility in allowing the delivery of planned chemotherapy dose on schedule, an important clinical goal especially in curative tumour settings. The high cost of these agents limits their widespread use. Current American Society of Clinical Oncology guidelines recommend primary prophylaxis, or first cycle use, with CSFs being confined to patients with > or = 40% risk of FN, which may include elderly patients and other high-risk patients. In addition to the risk of FN, primary prophylaxis should also be considered if the patient has risk factors that place them in the Special Circumstances category. These risk factors may include decreased immune function in patients who are already at an increased risk of infection and pre-existing neutropenia due to disease, extensive prior chemotherapy, or previous irradiation to the pelvis or other areas containing large amounts of bone marrow. Future studies are needed to better define the patients most likely to benefit from CSF therapy, both for prophylaxis and as an adjunct to antibiotics for treatment of FN. Other potential uses include combination therapy with stem cell factors and other cytokines to boost progenitor cell development, maintaining dose intensity of salvage therapy in metastatic cancer patients, and application in patients with pneumonia, Crohn's fistulas, diabetic foot infections and a variety of other infectious conditions.

Antineoplastic Agents↗