Major non-ABO incompatibility caused by anti-Jk(a) in a patient before allogeneic hematopoietic stem cell transplantation.

A 49-year-old white man with blood group AB, D+ was found to have alloanti-Jk(a) and -K when he developed a delayed hemolytic transfusion reaction before allogeneic hematopoietic stem cell transplant (HSCT). Given that his stem cell donor was blood group O, D+, Jk(a+), K-, rituximab was added to his conditioning regimen of fludarabine and melphalan to prevent hemolysis of engrafting Jk(a+) donor red blood cells. The patient proceeded to receive a peripheral blood stem cell transplant from a matched unrelated donor with no adverse events. To our knowledge, this is the first case of successful management of major non-ABO incompatibility caused by anti-Jk(a) in a patient receiving an allogeneic HSCT reported in the literature.

Acute leukemia and myelodysplasia after adjuvant chemotherapy for breast cancer: durable remissions after hematopoietic stem cell transplantation.

BACKGROUND: Although secondary acute leukemias and myelodysplasia are the known complications of adjuvant chemotherapy for breast cancer, the treatment outcome of these secondary malignancies is presently unclear. We examined the clinical and pathological features as well as the treatment results of a series of patients with acute leukemia/myelodysplasia arising after adjuvant chemotherapy for breast cancer. PATIENTS AND METHODS: Patients referred to our institution during a 5-year period for treatment of acute leukemia/myelodysplasia and who had received adjuvant chemotherapy for breast cancer are included. Leukemia-free survival for the whole group and for patients who underwent hematopoietic stem cell transplantation (HSCT) was estimated. RESULTS: Fifteen women (14 with acute leukemia and one with myelodysplasia) were identified. Seven of 15 patients had received an anthracycline, cyclophosphamide and a taxane. Ten patients developed acute leukemia/myelodysplasia with a latency period of 2 years or less from initiation of chemotherapy. Although mixed-lineage leukemia (MLL) rearrangement was the commonest chromosomal abnormality (8 of 15 patients), various other chromosomal abnormalities were also detected. Twelve of 15 patients underwent HSCT (11 allogeneic and one autologous). Eleven of these 12 patients who underwent HSCT were in remission at a median follow-up of 20.4 months (range 4.4-53.3 months). CONCLUSION: Durable remissions can be achieved in patients who develop acute leukemia/myelodysplasia secondary to adjuvant chemotherapy for breast cancer and are able to undergo allogeneic HSCT. Our results indicate that HSCT should be an early consideration in the management of such patients who are suitable candidates for the procedure.

Acute myeloid leukemia transforms the bone marrow niche into a leukemia-permissive microenvironment through exosome secretion.

Little is known about how leukemia cells alter the bone marrow (BM) niche to facilitate their own growth and evade chemotherapy. Here, we provide evidence that acute myeloid leukemia (AML) blasts remodel the BM niche into a leukemia growth-permissive and normal hematopoiesis-suppressive microenvironment through exosome secretion. Either engrafted AML cells or AML-derived exosomes increased mesenchymal stromal progenitors and blocked osteolineage development and bone formation in vivo. Preconditioning with AML-derived exosomes 'primed' the animals for accelerated AML growth. Conversely, disruption of exosome secretion in AML cells through targeting Rab27a, an important regulator involved in exosome release, significantly delayed leukemia development. In BM stromal cells, AML-derived exosomes induced the expression of DKK1, a suppressor of normal hematopoiesis and osteogenesis, thereby contributing to osteoblast loss. Conversely, treatment with a DKK1 inhibitor delayed AML progression and prolonged survival in AML-engrafted mice. In addition, AML-derived exosomes induced a broad downregulation of hematopoietic stem cell-supporting factors (for example, CXCL12, KITL and IGF1) in BM stromal cells and reduced their ability to support normal hematopoiesis. Altogether, this study uncovers novel features of AML pathogenesis and unveils how AML cells create a self-strengthening leukemic niche that promotes leukemic cell proliferation and survival, while suppressing normal hematopoiesis through exosome secretion.

Reduced-intensity conditioning for allogeneic hematopoietic stem cell transplantation with fludarabine and melphalan is associated with durable disease control in myelodysplastic syndrome.

We retrospectively evaluated the outcome of reduced-intensity conditioning (RIC) followed by allogeneic hematopoietic stem cell transplantation (HCT) in 43 patients with myelodysplastic syndrome (MDS) or AML arising from MDS. All patients received fludarabine plus melphalan followed by an allogeneic HCT from an HLA-identical sibling (SIB: n=19) or unrelated donor (MUD: n=24). Median age was 58 years (range: 30-71). Diagnoses at transplantation were RA (n=8), RARS (n=1), RAEB (n=13), RAEB-T (n=6), or AML arising from MDS (n=15). Of 28 patients with MDS, two patients had low, 10 had intermediate-1, nine had intermediate-2 and seven had high-risk MDS by IPSS criteria. All patients initially engrafted with the median neutrophil recovery of 15 days (range: 9-27). The 2-year overall survival, disease-free survival, relapse and transplant-related mortality were 53.5% (CI 45.2-61.1), 51.2% (CI 43.3-58.5), 16.3% (CI 7.9-30.7) and 35.2% (26.4-45.7), respectively. Grade II-IV acute graft-versus-host disease occurred in 27 (63%) patients. There was no significant survival difference between SIB and MUD-HCT, but the relapse rate was higher among SIB donor recipients when compared to MUD (38.5 versus 7%, P=0.02). RIC with fludarabine plus melphalan was associated with durable disease control and acceptable toxicity in this high-risk cohort.

Immunotherapy with acute leukemia cells modified into antigen-presenting cells: ex vivo culture and gene transfer methods.

Adult patients with acute leukemia have, in general, a poor prognosis, with long-term, disease-free survival achieved in only approximately one-third of cases. One of the proposed mechanisms for this poor overall response is the inability of the immune system to detect and eliminate residual malignant leukemia cells, which subsequently serve as a source of leukemic relapse. This review discusses the rationale of immunotherapy for acute leukemia and presents in vitro and in vivo model systems that were devised for pre-B acute lymphocytic leukemia (ALL) and acute myeloid leukemia (AML). New advances in the ex vivo manipulation of acute leukemia cells are presented, which attempt to modify these cells into functional antigen-presenting cells. These cells can then be used as autologous vaccines at the time of minimal residual disease after standard chemotherapy, to stimulate host immune responses against their own leukemia cells. The various approaches toward this aim include incubation of leukemia cells with cytokines or growth factors and gene manipulation of these cells. In particular, ex vivo culture of ALL cells with CD40 ligand, incubation of AML cells with granulocyte-macrophage colony-stimulating factor and interleukin-4 (GM-CSF/IL-4) and lentiviral transduction of ALL and AML cells for expression of immunomodulators (CD80 and GM-CSF) are current approaches under investigation for the development of autologous acute leukemia cell vaccines.

Transduction of acute myeloid leukemia cells with third generation self-inactivating lentiviral vectors expressing CD80 and GM-CSF: effects on proliferation, differentiation, and stimulation of allogeneic and autologous anti-leukemia immune responses.

Acute myeloid leukemia (AML) patients treated with available therapies achieve remission in approximately 60% of cases, but the long-term event-free survival is less than 30%. Use of immunotherapy during remission is a potential approach to increase survival. We propose to develop cell vaccines by genetic modification of AML cells with CD80, an essential T cell costimulator that is lacking in the majority of AML cases, and GM-CSF, to induce proliferation and activation of professional antigen-presenting cells. Here, we evaluated third generation self inactivating (SIN) lentiviral vectors, which have the potential advantage of improved safety. CD80 and GM-CSF expression by these vectors was higher than that reported with second generation vectors (Stripecke et al, Blood 2000; 96: 1317-1326). In some cases, endogenous GM-CSF expression by transduced AML cells induced phenotypic changes consistent with the maturation of leukemia blasts into antigen-presenting cells. Further, in all cases studied, GM-CSF expression was associated with higher proliferation and cell viability. Allogeneic and autologous mixed lymphocyte reactions performed with transduced irradiated AML cells expressing CD80 and/or GM-CSF demonstrated that expression of either transgene enhanced T cell activation. These pre-clinical data demonstrate the potential feasibility of third generation SIN vectors for use in AML immunotherapy.

Intraspinal hemorrhage complicating oral anticoagulant therapy: an unusual case of cervical hematomyelia and a review of the literature.

Intraspinal hemorrhage is a rare but dangerous complication of anticoagulant therapy. It must be suspected in any patient taking anticoagulant agents who complains of local or referred spinal pain associated with limb weakness, sensory deficits, or urinary retention. We describe a patient with hematomyelia, review the literature on hematomyelia and other intraspinal hemorrhage syndromes, and summarize intraspinal hemorrhage associated with oral anticoagulant therapy. The patient (a 62-year-old man) resembled previously described patients with hematomyelia in age and sex. However, he was unusual in having cervical rather than thoracic localization. As with intracranial bleeding, the incidence of intraspinal hemorrhage associated with anticoagulant therapy might be minimized by close monitoring and tight control of the intensity of anticoagulation. However, it is noteworthy that many of the reported cases were anticoagulated in the therapeutic range. If intraspinal hemorrhage is suspected, anticoagulation must be reversed immediately. Emergency laminectomy and decompression of the spinal cord appear mandatory if permanent neurologic sequelae are to be minimized. A high index of suspicion, prompt recognition, and immediate intervention are essential to prevent major morbidity and mortality from intraspinal hemorrhage.

Pathology of autoimmune myelofibrosis. A report of three cases and a review of the literature.

We identified 3 patients with autoimmune myelofibrosis (AM) lacking American Rheumatism Association criteria for systemic lupus erythematosus (SLE). They had 1 or 2 cytopenias and lacked serologic evidence for SLE. Autoimmune features included psoriatic arthritis and positive direct Coombs test (DCT) result, DCT-positive autoimmune hemolytic anemia, and synovitis with polyclonal hypergammaglobulinemia. Bone marrow biopsy specimens from each patient were evaluated by routine morphologic and immunohistochemical examination. They demonstrated marked hypercellularity (2 cases) or hypocellularity (1 case), moderate erythroid hyperplasia (all cases) with left-shifted maturation (2 cases), intrasinusoidal hematopoiesis (all cases), slightly to moderately increased megakaryocytes (2 cases), and grade 3 to 4 reticulin fibrosis (all cases). All lacked basophilia, eosinophilia, bizarre megakaryocytes, clusters of megakaryocytes, and osteosclerosis. Mild to moderate bone marrow lymphocytosis was noted in all cases. In 2 cases, increased small T cells and B cells formed nonparatrabecular, loose aggregates. AM is a clinicopathologic entity that may lack features of SLE. Loose aggregates of bone marrow T and B lymphocytes and the absence of morphologic and clinical features of myeloproliferative disease or low-grade lymphoproliferative disease are clues that distinguish AM from better known causes of bone marrow fibrosis.

Nontyphoidal Salmonella infection among recipients of hematopoietic SCT.

The incidence of nontyphoidal Salmonella (NTS) infections is rising worldwide and several outbreaks have been reported recently. Immunosuppressed patients are particularly vulnerable to NTS infections. We retrospectively examined the clinical features and outcomes of 18 recipients of hematopoietic SCT (HSCT) who were diagnosed with NTS infection at our institution during a 15-year period. Bacteremia was the most common presenting feature and occurred in 67% of cases. Diarrhea was absent in one-third of cases. Among 12 recipients of allogeneic HSCT, 8 presented with bacteremia and only 6 had diarrhea. A total of 9 of these 12 patients had chronic GVHD. Metastatic disease was distinctly rare and occurred in only two patients, whereas one patient died of NTS sepsis. Food safety practices to prevent NTS infection are important in HSCT recipients, particularly for those who have chronic GVHD after allogeneic HSCT.

Phase-2 trial of an intensified conditioning regimen for allogeneic hematopoietic cell transplant for poor-risk leukemia.

Patients with poor-risk leukemia have a high relapse rate despite allogeneic transplant. We report on the phase-2 trial of an intensified allogeneic transplant regimen whose aim was tolerable toxicity and durable remission. Study patients (n=30) had unfavorable first remission cytogenetics, progression from myelodysplasia or active disease due to induction failure or relapse. Conditioning was i.v. BU, targeted to a first-dose plasma area under the curve (AUC) of 700-900 µM min, VP-16 at 30 mg/kg of adjusted ideal body weight and fractionated TBI (FTBI) at 1200 cGy in 10 fractions. GVHD prophylaxis was CsA and mycophenolate mofetil. Regimen-related toxicities (Bearman) included grade II mucositis in 29 patients (97%) and grade III in one patient, grade II-III sinusoidal obstructive syndrome in 2 patients (7%), and grade 2-3 (CTC) skin toxicity in 8 patients (27%). The 30- and 100-day TRMs were 0 and 7% respectively. The median follow-up was 83.7 months (60.7-96.4) for surviving patients. The 5-year overall and disease-free survival was 40% for all patients. Cumulative 5-year relapse incidence (RI) was 23% and TRM was 37%. We have shown promising OS and RI in these poor-risk patients, who typically have few curative options.

Iron overload adversely affects outcome of allogeneic hematopoietic cell transplantation.

Iron overload is common in patients undergoing allogeneic hematopoietic cell transplantation (HCT) for hematologic disorders. Serum ferritin, a marker of tissue iron overload, was measured immediately before transplant in adult patients undergoing myeloablative HCT from matched sibling or unrelated donors. The effect of elevated pretransplant ferritin (defined as ferritin >or=1000 ng/ml) on day 100 mortality, overall survival, acute GVHD and infectious complications was assessed. Data on 190 patients were analyzed. In univariate analysis, the high-ferritin group had increased day 100 mortality (20 vs 9%, P=0.038), decreased overall survival (log-rank test: P-value=0.004), increased acute GVHD/death (63 vs 43%, P=0.009) and increased incidence of blood stream infections (BSIs)/death (60 vs 44%, P=0.042). In a multivariate analysis, high ferritin was associated with increased risk of death (Cox model: hazard ratio=2.28, P=0.004), increased day 100 mortality (generalized linear model (GLM) odds ratio=3.82, P=0.013), increased incidence of acute GVHD/death (GLM odds ratio=3.11, P=0.001) and increased risk of BSI/death (GLM odds ratio=1.99, P=0.032). The results remained similar when serum ferritin was considered a continuous variable. Elevated serum ferritin adversely impacts on overall survival and increases the likelihood of acute GVHD and BSI after allogeneic HCT.

Mast cell disease associated with acute myeloid leukemia: detection of a new c-kit mutation Asp816His.

Mast cell disease (MCD), a proliferation of mast cells (MC), is occasionally associated with hematologic malignancies. Neoplastic MC have activating c-kit mutations. c-kit is a receptor tyrosine kinase required for the development, proliferation, and survival of MC. Interaction of c-kit with its ligand stem cell factor induces dimerization, receptor phosphorylation, and signal transduction. The most common c-kit mutation detected in neoplastic MCD is Asp816Val, which results in ligand-independent autophosphorylation of the receptor leading to MC proliferation. We describe the rare occurrence of MCD associated with acute myeloid leukemia, report a novel c-kit mutation Asp816 His, and discuss the pathogenesis of MCD associated with hematologic malignancies.

Ticlopidine-induced aplastic anemia: development of chromosomal abnormalities and response to immunosuppressive therapy.

Severe aplastic anemia is a well-recognized complication of ticlopidine therapy that carries a high mortality. Therapy with colony-stimulating factors or corticosteroids has been largely ineffective in this disorder. We report a case of ticlopidine-induced aplastic anemia that was successfully treated with cyclosporine and high-dose dexamethasone. The patient rapidly responded to immunosuppressive therapy and had a normal hemogram after cessation of immunosuppression. On long-term follow-up, the patient developed a progressive macrocytic anemia. Repeat bone marrow evaluation demonstrated myelodysplasia with erythroid hypoplasia. An associated chromosomal abnormality consisting of a t(3;16) (q21; p13.3) translocation was detected. This is the first report of a chromosomal abnormality associated with ticlopidine induced marrow aplastic anemia.

A phase I study of a HER2/neu bispecific antibody with granulocyte-colony-stimulating factor in patients with metastatic breast cancer that overexpresses HER2/neu.

A phase I study of escalating doses of humanized bispecific antibody (bsAb) MDX-H210 with granulocyte-colony-stimulating factor (G-CSF) was conducted in patients with metastatic breast cancer that overexpressed HER2/neu. The main objectives of the study were to define the maximal tolerated dose (MTD) of MDX-H210 when combined with G-CSF, to measure the pharmacokinetics of MDX-H210 when administered with G-CSF, and to determine the toxicity, biological effects and possible therapeutic effect of MDX-H210 with G-CSF. MDX-H210 is a F(ab)' x F(ab)' humanized bispecific murine antibody that binds to both HER2/neu and the FcgammaR1 receptor (CD64), and was administered intravenously weekly for three doses followed by a 2-week break and then three more weekly doses. A total of 23 patients were treated, and doses were escalated from 1 mg/m2 to 40 mg/m2 with no MTD reached. The toxicity of the bsAb + G-CSF combination was modest, with no dose-limiting toxicity noted: 19 patients had fevers, 7 patients had diarrhea, and 3 patients had allergic reactions that did not limit therapy. The beta-elimination half-life varied from 4 h to 8 h at doses up to 20 mg/m2. Significant release of cytokines interleukin-6, G-CSF, and tumor necrosis factor alpha was observed after administration of bsAb. Circulating monocytes disappeared within 1 h of bsAb infusion, which correlated with binding of bsAb, noted by flow-cytometric analysis. Significant levels of human anti-(bispecific antibody) were measured in the plasma of most patients by the third infusion. No objective clinical responses were seen in this group of heavily pre-treated patients.