Spontaneous splenic rupture with fatal outcome following G-CSF administration for myelodysplastic syndrome

Managing common toxicities associated with checkpoint inhibitor and chemotherapy combinations for untreated classic Hodgkin lymphoma

Combination checkpoint inhibitor (CPI) and chemotherapy is an effective and safe treatment strategy for patients with untreated classic Hodgkin lymphoma. Recent studies of programmed cell death protein 1 inhibitors combined with doxorubicin, vinblastine and dacarbazine have demonstrated high overall and complete response rates. This combination has a unique toxicity profile that should be managed appropriately so as not to compromise treatment efficacy. Common toxicities include rash, hepatoxicity, neutropenia and thyroid dysfunction. Here, we present four cases and the management strategies around such toxicities. In addition, we highlight key clinical decision-making around the administration of subsequent doses of CPI and chemotherapy.

Unexpected death involving the spleen - an overview

The spleen is located in the left upper quadrant of the abdominal cavity and has both immunological and haematological functions. A variety of quite different entities may be associated with sudden death due to splenic involvement. These range from simple traumatic disruption of the parenchyma of a normal spleen with marked intra-abdominal haemorrhage, to conditions such as malaria and infectious mononucleosis where splenomegaly predisposes to rupture. Haematological diseases such as malignancies and haemoglobinopathies may causes sudden death due to haemorrhage or red cell sequestration. Asplenia or polysplenia may be associated with significant congenital heart disease. Hyposplenia, both structural and functional, may also result in rapid demise from sometimes unusual bacterial infections. Vascular abnormalities causing death include entities such as splenic artery aneurysms. Thus, deaths from splenic pathology may be due to localised issues or may be part of more generalised disease. For this reason the autopsy in cases of splenic-associated deaths must be comprehensive and include special testing such as microbiological screening and/or haematologic/genetic evaluation.

Splenic rupture following lenograstim in post-autologous stem cell transplantation treated with emergency open splenectomy: a case report and literature review

Granulocyte-colony stimulating factors (G-CSFs) are the cornerstone of peripheral blood stem cell mobilization and apheresis. However, splenic rupture following G-CSF treatment represents a serious and potentially fatal adverse event. Here, we report the case of a patient in their late 50s with severe pancytopenia post-autologous stem cell transplantation reinfusion suffering from splenic rupture after treatment with lenograstim. We also reviewed the literature describing cases of splenic rupture during G-CSF administration.

Effectiveness of Herbal Medicine for Leukopenia/Neutropenia Induced by Chemotherapy in Adults with Colorectal Cancer: A Systematic Review and Meta-analysis

Objective:

To evaluate the effectiveness of Chinese Herbal Medicine (CHM) on leukopenia/neutropenia induced by chemotherapy in adults with colorectal cancer (CRC).

Methods:

Eight electronic databases were searched from their inception to June 2020. Randomized controlled trials with clarified sequence generation were qualified. Two reviewers independently conducted the screening and data extraction. Methodological quality was assessed using the Risk of Bias tool. RevMan 5.4 was applied to the meta-analysis.

Results:

Twenty-seven studies involving 1867 participants were qualified, of which 26 were included in the quantitative synthesis. Meta-analysis showed that CHM significantly reduced the incidence of leukopenia induced by chemotherapy (RR = 0.69; 95% CI 0.59-0.82), as well as the grade 3/4 leukopenia (RR = 0.71; 95% CI 0.55-0.90). Meanwhile,CHM decreased the occurrence of neutropenia (RR = 0.52, 95% CI 0.35-0.77), especially for the grades 3/4 neutropenia (RR = 0.42, 95% CI 0.27-0.64). Twenty-six of the included studies focused on the adverse events related to CHM.

Conclusion:

CHM may relieve neutropenia/leukopenia induced by chemotherapy in adults with colorectal cancer.

G-CSF shifts erythropoiesis from bone marrow into spleen in the setting of systemic inflammation

The anemia of inflammation is related in part to abnormal erythropoiesis in bone marrow. G-CSF regulates granulopoiesis and is increased during systemic inflammation. Here, we have showed that high levels of G-CSF are associated with repression of bone marrow erythropoiesis and expansion of splenic erythropoiesis in Escherichia coli-infected mice and lipopolysaccharide-treated mice. Under lipopolysaccharide-induced systemic inflammatory conditions in mice, G-CSF neutralization with antibody alleviated the blockage of bone marrow erythropoiesis, prevented the enhancement of splenic erythropoiesis, ameliorated splenomegaly, and reduced the brittleness of spleen. We further demonstrated that after lipopolysaccharide treatment, TLR4-knockout mice display low levels of G-CSF, healthy bone marrow erythropoiesis, almost no stress erythropoiesis in the spleen, and normal size and toughness of spleen. In addition, we found HIF-mediated erythropoietin production is essential for splenic erythropoiesis in the setting of G-CSF-induced suppression of bone marrow erythropoiesis. Our findings identify G-CSF as a critical mediator of inflammation-associated erythropoiesis dysfunction in bone marrow and offer insight into the mechanism of G-CSF-induced splenic erythropoiesis. We provide experimentally significant dimension to the biology of G-CSF.

Myocarditis and carotidynia caused by Granulocyte-Colony stimulating factor administration

A 59 year-old woman was treated with adjuvant chemotherapy for triple negative breast cancer (TNBC) stage IB. She received pegfilgrastrim as secondary prophylaxis of neutropenia. After administration of pegfilgrastrim on day 11, she was hospitalised because of carotidynia and myocarditis that improved with antibiotics and steroids as an infection was suspected. Once she was recovered, another cycle of chemotherapy with pegfilgrastrim was administrated. At this time, the patient presented to our hospital with fever, odynophagia and chest pain, with diagnosis of myocarditis coupled with cardiogenic shock. She received antibiotics and steroids, advanced life support and also a pericardial window was done, with recovery of her condition. After a complete evaluation and exclusion of other possible aetiologies, we concluded that pegfilgrastrim was responsible for inducing carotidynia and myocarditis. Few cases have been published about Granulocyte-Colony stimulating factor (G-CSF) induced carotidynia and aortitis. However, this is the first reported case about G-CSF induced myocarditis and carotidynia.

Atraumatic idiopathic splenic rupture induced by granulocyte-colony stimulating factor (G-CSF) for the treatment of pancytopenia, managed successfully by laparoscopic splenectomy

Splenic rupture is a potentially life-threatening condition and an uncommon short-term complication of granulocyte-colony stimulating factor (G-CSF) administration. It may present as acute abdominal pain or suddenly precipitously worsening anaemia with haemodynamic instability that requires urgent operative intervention for survival. We present a case of an atraumatic idiopathic splenic rupture in University Hospital, Ayr in a patient who received G-CSF treatment for chemotherapy-induced (methotrexate) pancytopenia and was successfully managed by laparoscopic splenectomy.

A provider's guide to primary myelofibrosis: pathophysiology, diagnosis, and management

Although understanding of the pathogenesis and molecular biology of primary myelofibrosis continues to improve, treatment options are limited, and several biological features remain unexplained. With an appropriate clinical history, exam, laboratory evaluation, and bone marrow biopsy, the diagnosis can often be established. Recent studies have better characterized prognostic factors and driver mutations in myelofibrosis, facilitated by use of next-generation sequencing. These advances have facilitated development of a management strategy that is based on both risk factors and clinical phenotype. For low-risk patients, treatment will depend on symptom severity. For patients with higher-risk disease, several treatments are available including JAK inhibitors, allogeneic hematopoietic stem cell transplant, and clinical trials using novel molecularly targeted therapies and rational drug combinations. In this review, we outline what is known about the disease pathogenesis, discuss an approach to reaching the diagnosis, review the prognosis of myelofibrosis, and detail current therapeutic strategies.

Pegfilgrastim-associated large-vessel vasculitis developed during adjuvant chemotherapy for breast cancer: A case report and review of the literature

Introduction

Granulocyte colony-stimulating factor (G-CSF) is widely used as a neutrophil supportive therapy in breast cancer chemotherapy. Common adverse events of G-CSF include bone pain, headache, and fatigue; however, reports of G-CSF-associated vasculitis are few.

Case report

A 66-year-old woman who had undergone surgery for breast cancer received adjuvant chemotherapy with prophylactic use of pegfilgrastim (peg-G). She developed peg-G-associated vasculitis 11 days after initially receiving peg-G. Management and outcome: Although various blood and culture tests were required to rule out other vasculitis syndromes and infections, her symptoms spontaneously disappeared without any treatment other than discontinuation of the causal drug.

Discussion

G-CSF-associated vasculitis is occasionally accompanied by severe complications such as aortic dissection and aneurysm formation. This case report is important to draw attention towards this rare and difficult-to-diagnosis adverse event of peg-G.

Spontaneous splenic rupture as a rare complication of G-CSF injection

Splenic rupture is an infrequent and underdiagnosed side effect of granylocyte colony-stimulating factor (G-CSF). We report the case of a 54-year-old woman with brain and bone metastasis in a lung adenocarcinoma who was admitted for faintness 28 days after a G-CSF injection. Abdominal CT scan confirmed the diagnosis of splenic rupture. A conservative treatment was chosen using a peritoneal cleansing during laparoscopic surgery. Clinicians should be aware of this rare toxicity as it could be severe, but easily reversible using appropriate surgical treatment. Even if prognosis remains poor for patients with lung cancer, invasive procedures could be considered in this rapidly evolving setting, especially in case of reversible adverse event.

Spontaneous subcapsular splenic hematoma associated with filgrastim in a patient undergoing allogeneic hematopoietic stem cell transplantation

OBJECTIVE

To report the development of a spontaneous subcapsular splenic hematoma following filgrastim administration in a patient undergoing an allogeneic hematopoietic stem cell transplant.

CASE SUMMARY

A 60-year-old female with myelodysplastic syndrome was admitted for a reduced-intensity allogeneic hematopoietic stem cell transplant from an unrelated donor. She received filgrastim 5 μg/kg starting on day 1 to accelerate neutrophil recovery. On day 5, she began reporting severe left chest-wall pain. Contrast-enhanced computed tomography of the abdomen/pelvis revealed a spontaneous subcapsular splenic hematoma. Upon discontinuation of filgrastim, the pain fully resolved. The patient was subsequently rechallenged with filgrastim, which led to recurrence of the left-sided chest-wall pain. Filgrastim was discontinued and the patient reported resolution of the pain.

DISCUSSION

Filgrastim has been associated with splenic hematoma and splenic rupture, predominantly in healthy donors undergoing mobilization of peripheral blood stem cells. Although splenic rupture attributed to filgrastim in a patient undergoing allogeneic hematopoietic stem cell transplantation has been reported, to our knowledge, this is the first case report to establish causality. Using the Naranjo probability scale, an objective causality assessment revealed that the adverse drug event was highly probable.

CONCLUSIONS

Although filgrastim-induced splenomegaly, splenic hematomas, and splenic rupture are rare, clinicians working in the bone marrow transplant setting should be cognizant of the potential of growth factors to cause these adverse events.

Lentiviral gene transfer regenerates hematopoietic stem cells in a mouse model for Mpl-deficient aplastic anemia

Thpo/Mpl signaling plays an important role in the maintenance of hematopoietic stem cells (HSCs) in addition to its role in megakaryopoiesis. Patients with inactivating mutations in Mpl develop thrombocytopenia and aplastic anemia because of progressive loss of HSCs. Yet, it is unknown whether this loss of HSCs is an irreversible process. In this study, we used the Mpl knockout (Mpl(-/-)) mouse model and expressed Mpl from newly developed lentiviral vectors specifically in the physiologic Mpl target populations, namely, HSCs and megakaryocytes. After validating lineage-specific expression in vivo using lentiviral eGFP reporter vectors, we performed bone marrow transplantation of transduced Mpl(-/-) bone marrow cells into Mpl(-/-) mice. We show that restoration of Mpl expression from transcriptionally targeted vectors prevents lethal adverse reactions of ectopic Mpl expression, replenishes the HSC pool, restores stem cell properties, and corrects platelet production. In some mice, megakaryocyte counts were atypically high, accompanied by bone neo-formation and marrow fibrosis. Gene-corrected Mpl(-/-) cells had increased long-term repopulating potential, with a marked increase in lineage(-)Sca1(+)cKit(+) cells and early progenitor populations in reconstituted mice. Transcriptome analysis of lineage(-)Sca1(+)cKit(+) cells in Mpl-corrected mice showed functional adjustment of genes involved in HSC self-renewal.

Gene therapy for β-thalassaemia: the continuing challenge

The β-thalassaemias are inherited anaemias that form the most common class of monogenic disorders in the world. Treatment options are limited, with allogeneic haematopoietic stem cell transplantation offering the only hope for lifelong cure. However, this option is not available for many patients as a result of either the lack of compatible donors or the increased risk of transplant-related mortality in subjects with organ damage resulting from accumulated iron. The paucity of alternative treatments for patients that fall into either of these categories has led to the development of a revolutionary treatment strategy based on gene therapy. This approach involves replacing allogeneic stem cell transplantation with the transfer of normal globin genes into patient-derived, autologous haematopoietic stem cells. This highly attractive strategy offers several advantages, including bypassing the need for allogeneic donors and the immunosuppression required to achieve engraftment of the transplanted cells and to eliminate the risk of donor-related graft-versus-host disease. This review discusses the many advances that have been made towards this endeavour as well as the hurdles that must still be overcome before gene therapy for β-thalassaemia, as well as many other gene therapy applications, can be widely applied in the clinic.

Mobilization of hematopoietic stem cells in a thalassemic mouse model: implications for human gene therapy of thalassemia

Granulocyte colony-stimulating factor (G-CSF)-mobilized blood stem cells may become the preferable source of hematopoietic stem cells (HSCs) for gene therapy because of the higher yield of cells compared with conventional bone marrow harvesting. A G-CSF-associated risk of splenic rupture has been recognized in normal donors of HSCs, but limited information is available about the G-CSF effect in the presence of splenomegaly and extramedullary hematopoiesis. We investigated the G-CSF effect in a thalassemic mouse model (HBB(th-3)) as compared with a normal strain (C57BL/6), in terms of safety, mobilization efficacy, and distribution of stem cells among hematopoietic compartments. There was no death or clinical sequelae of splenic rupture in G-CSF-treated animals of either strain; however, hemorrhagic infarcts in the spleen were detected with low frequency in G-CSF-treated HBB(th-3) mice (12.5%). HBB(th-3) mice mobilized less effectively than C57BL/6 mice (Lin(-)Sca-1(+)c-Kit(+) cells/microl of peripheral blood mononuclear cells [PBMCs]: 90 +/- 55 vs. 255 +/- 174, respectively, p = 0.01; CFU-GM/ml PBMCs: 390 +/- 262 vs. 1131 +/- 875, p = 0.01) because of increased splenic trapping of hematopoietic stem and progenitor cells (Lin(-)Sca-1(+)c-Kit(+) cells per spleen (x10(5)): 487 +/- 35 vs. 109 +/- 19.6, p = 0.01; CFU-GM per spleen (x10(2)): 1470 +/- 347 vs. 530 +/- 425, p = 0.0006). Splenectomy restored the mobilization proficiency of thalassemic mice at comparable levels to normal mice and resulted in the development of a hematopoietic compensatory mechanism in the thalassemic liver that protected splenectomized mice from severe anemia. Our data imply that, in view of human gene therapy for thalassemia, either multiple cycles or alternative ways of mobilization may be required for a sufficient yield of transplantable HSCs. In addition, strategies to minimize the risk of G-CSF-induced splenic infarcts should be explored in a clinical setting.

Bone marrow harvest versus peripheral stem cell collection for haemopoietic stem cell donation in healthy donors

BACKGROUND

Haemopoietic stem cells can be collected from a donor either as a bone marrow harvest or by peripheral blood collection. Both techniques have risks for the donor.

OBJECTIVES

The aim of this review was to identify the adverse effects of haemopoietic stem cell donation and to compare the tolerability and safety of the two methods.

SEARCH STRATEGY

We searched bibliographic databases including the Cochrane Central Register of Controlled trials (CENTRAL) (The Cochrane Library 2008, issue 2), MEDLINE and EMBASE up to May 2008. We also searched reference lists of articles and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials enrolling haemopoietic stem cell donors and evaluating the different methods of donating haemopoietic stem cells were eligible.

DATA COLLECTION AND ANALYSIS

Two authors independently screened studies for inclusion. We extracted data and evaluated methodological quality. Quantitative analysis was not possible for most outcomes, but where used we preferred random-effects models due to the variability between the included studies.

MAIN RESULTS

Six trials (807 donors) were eligible: all were substudies, or constituent parts of, larger randomised controlled trials of bone marrow and peripheral blood stem cell allogeneic transplantation. No included trial was designed solely to measure and assess the experience of stem cell donors. The donors in all studies were related to the stem cell recipient. Overall, both types of donors experienced pain subsequent to donation, and psychological morbidity. The trend was for bone marrow donors to experience more pain at the donation site, more overall adverse events, and more days of restricted activity. They were also more likely to require hospitalisation than peripheral blood stem cell donors. In contrast, peripheral blood stem cell donors experienced more pain prior to donation, which may be related to the pre-donation administration of granulocyte colony stimulating factor (G-CSF). The methodological quality of the studies was poor and indicated limitations due to the risk of selection and attrition bias. The proportion of donors from the parent trial not included in the donor substudies was also inadequately explained.

AUTHORS' CONCLUSIONS

The different short-term morbidities associated with each type of haemopoietic stem cell donation were clear, with bone marrow donors experiencing more pain and more restriction post-donation than peripheral blood donors. However, the studies were limited by their methodological quality, failure to provide long-term follow up (for which larger numbers of donors would be required) and a failure to apply consistent measures of quality of life in a way which allows more meaningful evaluation across studies.

Splenic rupture, secondary to G-CSF use for chemotherapy induced neutropenia: a case report and review of literature

Introduction

Chemotherapy Induced neutropenia is a frequent and serious complication of cytotoxic cancer treatment.

Granulocyte colony stimulating factors (G-CSF) are frequently used to counter neutropenia, attempt rapid recovery of patients and allow for continuation of treatment without compromise on dose, especially in curative malignancies. Generally regarded as safe, G-CSF use has been very rarely reported to have resulted in serious side effects, such as, splenic rupture.

Case presentation

We are reporting a case of a twenty years old man, who was being treated for T cell acute lymphoblastic leukemia and received colony stimulating factors for treatment of severe neutropenia and suffered from splenic rupture, He was treated with splenectomy.

Conclusion

Although extremely rare, splenic rupture can be a serious and sometimes life threatening complication of high dose colony stimulating factors therapy.

Granulocyte colony-stimulating factor administration: adverse events

Recombinant human granulocyte colony-stimulating factor (G-CSF) has been in clinical use for approximately 2 decades. In healthy donors, it has been used to mobilize peripheral blood progenitor cells for hematopoietic stem cell transplantation and granulocytes for apheresis collection. In patients, it has been used to decrease the duration of neutropenia after chemotherapy and to offset the neutropenia due to myelodysplasia, acquired immunodeficiency syndrome, and genetic disorders of granulocyte production. As the number of uses of G-CSF in clinical practice grows, more side effects of this generally safe pharmaceutical agent are being recognized. Our objective in this article is to provide an in-depth review of the reported adverse events associated with the use of G-CSF.

Splenic rupture in a patient with plasma cell myeloma following G-CSF/GM-CSF administration for stem cell transplantation and review of the literature

Recipients of granulocyte-colony stimulating factor/granulocyte macrophage-colony stimulating factor are not only individuals with underlying disorders, but also healthy donors undergoing peripheral blood progenitor cell (PBPC) mobilization. In addition to the known adverse effects associated with G-CSF, complications such as splenic rupture have also been reported. A review of the English literature, with addition of a patient with plasma cell myeloma, reveals that splenic rupture occurs not only in patients with underlying disease, but also in healthy PBPC donors. Although the cause of splenic rupture does not appear to be associated with any specific condition, physicians should be alerted to the possibility of this potentially fatal complication in individuals receiving G-CSF therapy.

Granulocyte-colony stimulating factor administration to healthy individuals and persons with chronic neutropenia or cancer: an overview of safety considerations from the Research on Adverse Drug Events and Reports project

Granulocyte-colony stimulating factor (G-CSF) is widely administered to donors who provide peripheral blood stem cells (PBSC) for individuals who undergo hematopoietic stem cell transplants. Questions have been raised about the safety of G-CSF in this setting. Herein, the Research on Adverse Drug Events and Reports (RADAR) project investigators reviewed the literature on G-CSF-associated adverse events in healthy individuals or persons with chronic neutropenia or cancer. Toxicities identified included bone pain and rare instances of splenic rupture, allergic reactions, flares of underlying autoimmune disorders, lung injury and vascular events. Among healthy individuals, four patients developed splenic rupture shortly after G-CSF administration and three patients developed acute myeloid leukemia 1 to 5 years after G-CSF administration. Registry studies identified no increased risks of malignancy among healthy individuals who received G-CSF before PBSC harvesting. However, more than 2000 donors would have to be followed for 10 years to detect a 10-fold increase in leukemia risk. Our review identifies bone pain as the most common toxicity of G-CSF administration. There are questions about a causal relationship between G-CSF administration and acute leukemia, but more long-term safety data from database registries are needed to adequately evaluate such a relationship.

Spontaneous splenic haematoma in a multiple myeloma patient receiving pegfilgrastim support

Growth factors are a significant advance in the supportive care of patients with cancer with a wide range of indications. Frequent side effects of G-CSF include bone pain, headache, fatigue and nausea. We report a case of subcapsular splenic haematoma following pegfilgrastim administration in a 65-year old patient with multiple myeloma. Proposed mechanisms accounting for splenic enlargement include extramedullary haemopoiesis, intrasplenic infiltration by mature and immature myeloid cells and intrasplenic stem cell homing and proliferation. The risk of spontaneous splenic rupture is difficult to quantify. Physicians should be aware of this life-threatening condition and early diagnosis can be difficult since anemia and splenomegaly are common findings in haematologic patients.

Feasibility and safety of G-CSF administration to induce bone marrow-derived cells mobilization in patients with end stage liver disease

BACKGROUND/AIMS

To evaluate feasibility, safety and pattern of bone marrow-derived cells (BMC) mobilization in patients with end stage liver cirrhosis following granulocyte-colony stimulating factor (G-CSF) administration.

METHODS

Eight patients with severe liver cirrhosis (Child-Pugh score B-C, spleen diameter less than 170 mm) were included. They were treated with G-CSF (5 microg/kg b.i.d for three consecutive days) to mobilize BMC, evaluated as circulating CD34+ve cells (flow cytometry) and myeloid CFU-GM progenitors (in vitro colony growth assay). Co-expression in CD34+ve cells markers of differentiation (Thy1, CD133, CXCR4, c1qRp) were investigated on CD34+ve cells by double direct immunofluorescence. Data from 40 healthy haematopoietic stem cell donors were used as controls.

RESULTS

Mobilization of CD34+ve cells occurred in all patients. It was paralleled by expansion of circulating CFU-GM progenitors. Circulating CD34+ve cells co-expressed epithelial and stem cell markers in both cirrhotics and volunteer stem cell donors. G-CSF was well tolerated, no adverse event occurred, a significant reversible increase of splenic longitudinal diameter was observed.

CONCLUSIONS

(i) G-CSF mobilization of BMC co-expressing epithelial and stem markers occurred in all cirrhotic patients; (ii) splenomegaly up to 170 mm does not prevent safe BMC mobilization following G-CSF in patients with end stage liver disease; (iii) mobilized BMC may represent an easy immature cell source potentially useful for novel approaches for liver regeneration.

Effects of granulocyte-colony-stimulating factor on mobilization of bone-marrow-derived stem cells after myocardial infarction in humans

Recent experimental studies have shown that granulocyte-colony-stimulating factor (G-CSF) enhanced cardiac function after infarction. The concept of direct cytokine or cell-mediated effects on postischemic myocardial function was tested in the setting of human myocardial infarction subjected to percutaneous coronary intervention. In the FIRSTLINE-AMI study 50 consecutive patients with first ST-elevation myocardial infarction were randomly assigned to receive either 10 microg/kg G-CSF for 6 days after percutaneous coronary intervention in addition to standard medication, or standard care alone. G-CSF administration led to mobilization of CD34(+) mononuclear stem cells (MNC(CD34+)), with a 20-fold increase to 64 +/- 37 MNC(CD34+)/microl at day 6 without significant associated changes in rheology, blood viscosity or inflammatory reaction, or any major adverse effects. At 4 months the G-CSF group showed improved left ventricular ejection fraction of 54 +/- 8% versus 48 +/- 4% at baseline (P <0.001), and no evidence of left ventricular end-diastolic remodeling, with a diameter of 55 +/- 5 mm and improved segmental wall thickening (P <0.001); conversely, in control patients left ventricular ejection fraction was 43 +/- 5% at 4 months (P <0.001), with increased left ventricular end-diastolic dimension of 58 +/- 4 mm (P <0.001), and no segmental wall thickening. In conclusion, the FIRSTLINE-AMI study showed that G-CSF administration and mobilization of MNC(CD34+) after reperfusion of infarcted myocardium may offer a pragmatic strategy for preservation of human myocardium and prevention of remodeling without evidence of aggravated atherosclerosis.