Academic literature on the topic 'TP 7.5 UL 2008'

Abstract Abstract 266 Neonatal alloimmune thrombocytopenia (NAIT) is caused by maternal antibodies specific for fetal platelet antigens and is the most common cause of intracranial hemorrhage in full term infants. The antigen HPA-1a, carried on beta 3 integrin (GPIIIa), is the most common trigger for NAIT and the 2% of women who are HPA-1a-negative are at risk to produce such antibodies. Most HPA-1a antibodies causing NAIT can be easily detected but it is not rare for an HPA-1a negative mother who lacks detectable antibodies to give birth to an infant with thrombocytopenia. Several recent reports suggest that low avidity HPA-1a antibodies not detected by conventional serologic methods are responsible for some of these cases (Socher 2009, Bakchoul 2011). To examine this question, we retroactively analyzed a cohort of 3478 suspected NAIT cases referred for laboratory diagnosis. Among 677 HPA-1a-negative mothers, we identified 61 in whom HPA-1a-specific antibodies were not detected by conventional methods. Surface plasmon resonance (SPR) analysis enables ligand-receptor interaction to be studied in real time without washing the target. Using this approach, we studied reactions of IgG from the 61 archived serum samples against purified GPIIb/IIIa isolated from group O platelets and identified 18 samples that reacted preferentially with the HPA-1a-positive version of the integrin in comparison with HPA-1a-negative integrin. Information defining clinical status was obtained on 13 of these cases by follow-up communication. Seven cases had been referred because of neonatal thrombocytopenia. Platelet nadirs ranged from 8,000/ul to 141,000/ul (median 38,000/ul). Five of the 7 infants had bleeding and were given maternal platelet transfusions and/or IVIgG. Normal platelet counts were achieved after 4 to 70 days (median 7 days). One infant had a normal platelet count, however IVIgG had been given to its mother throughout pregnancy. The remaining 5 cases were referred in mid-pregnancy because an HPA-1a-negative sister previously gave birth to an infant with NAIT. Four of these infants had normal platelets at birth; one had mild TP (platelets 125,000/ul). Only 3 of 12 mothers typed for HLA were positive for HLA-DRB3*0101, a marker found in >95% of women who make “conventional” HPA-1a antibodies during pregnancy (p < 0.001). The ability of human antibodies to cause destruction of human platelets in vivo can be studied in the NOD/SCID mouse, which lacks xenoantibodies normally found in other species (Newman 2007). Serum from 4 mothers was available in quantities sufficient for mouse studies; three of the four maternal sera caused accelerated destruction of HPA-1a-positive, but not HPA-1a-negative platelets. These findings indicate that low-avidity HPA-1a antibodies not detectable by conventional serologic methods are made by a subset of women exposed to the HPA-1a antigen during pregnancy and that some, but not all of these antibodies are capable of causing NAIT, which is usually mild, but can be severe. Women negative for HLA-DRB3*0101 may be especially prone to produce antibodies of this type. Maternal-fetal incompatibility for platelet antigens other than HPA-1a is very common and many apparent NAIT cases not involving HPA-1a go unresolved. The possibility that low avidity antibodies specific for antigens other than HPA-1a are responsible for some of these cases deserves study. Disclosures: No relevant conflicts of interest to declare.

Abstract Numerous drugs are known to cause immune thrombocytopenia (TP) mediated by antibodies (abs) that bind to platelets only when the sensitizing drug is present in soluble form. The widely used antibiotic, vancomycin, has been implicated as a cause of TP only in 8 case reports and little is known about antibodies possibly responsible for this complication. We characterized clinical and serologic aspects of TP occurring in 39 patients during treatment with vancomycin. In this group, TP developed after 1–27 days of treatment (median 6 days) and plt nadirs ranged from 1,000 to 60,000 plts/uL (median 14,000 plts/uL). Bleeding occurred in 14 patients and contributed to a fatal outcome in 3. TP persisted for 1–17 days after discontinuing vancomycin (median 7 days). Platelets eventually returned to baseline in all surviving patients. Serum obtained after the onset of TP was studied for vancomycin-dependent, platelet-reactive abs by flow cytometry and by solid phase ELISA using immobilized plt glycoproteins (GP) as targets. Vancomycin-dependent antibodies detected in patients and normal subjects IgG only IgM only IgG + IgM No antibody Total Patients with TP 21 (54%) 5 (13%) 13 (33%) (0)%) 39 Normal individuals 58 (21%) 4 (1%) 1 (0%) 210 (77%) 273 Results of flow cytometric studies are summarized above. All patients had IgG and/or IgM abs that reacted with normal plts in the presence, but not in the absence of vancomycin. The IgG mean fluorescence intensity (MFI) signal in the presence of drug was 1.6 to 32.0 times stronger (mean ratio 5.7) than that obtained in the absence of drug. Vancomycin-dependent IgG abs were also identified in 59 of 273 normal individuals but were much weaker than abs detected in patients (p = 0.004). IgM abs (mean ratio 5.7, range 1.6 – 34) were found in 18 of 39 patients (46%). Weaker IgM abs were found in only 5 of 273 normal subjects (1.8%) (p = 0.001). Two patient abs studied in ELISA reacted preferentially with GPIIb/IIIa. Studies to determine the frequency of abs in patients given vancomycin who do not develop TP are in progress. These findings provide evidence that TP in patients given vancomycin can be caused by drug-dependent abs specific for GPIIb/IIIa that are stimulated by vancomycin exposure. IgG and IgM abs in patients with TP are generally much stronger than drug-dependent, platelet-reactive immunoglobulins found in some normal subjects. The significance of the latter abs is presently unknown. Drug-dependent IgM abs are found almost exclusively in patients with vancomycin-associated TP and may be diagnostic. Patients treated with vancomycin often have life-threatening bacterial sepsis and may have various reasons for developing TP. Serologic testing for drug-dependent, platelet-reactive IgG and IgM abs may provide a means of identifying those in whom vancomycin should be discontinued.

590 Background: CMF (C 600 mg/m2, M 40 mg/m2, F 600 mg/m2) is an option for adjuvant therapy for patients with low risk early stage breast cancer. DD regimens as predicted by mathematical models of cancer growth and treatment response are superior. We previously demonstrated the safety of DD EC (epirubicin/cyclophosphamide) followed by paclitaxel at 10–11 day (d) intervals. We investigated the feasibility of administering DD adjuvant CMF every 14 d and then every 10–11 d in a 2-stage phase II trial. Methods: An initial cohort (A) was treated q 14 d with PEG-filgrastim (Neulasta) support. A second cohort (B) was treated every 10–11 d with filgrastim/Neupogen x 5 d and then, based on feasibility, modified (cohort C) to use 7 d filgrastim. The primary end point was feasibility defined as having ANC > 1.5 x 103/uL on day 1 of planned treatment for all 8 cycles with no grade 3 or higher non-hematologic toxicity. All three cohorts were tested using a Simon's two-stage optimal design with type I and type II errors set at 10%. This design would effectively discriminate between true tolerability (as protocol-defined) rates of< 60% and> 80%. Cohort A: 38 pts with early stage breast cancer were accrued from 3/2008 though 6/2008. Cohort B: 7 pts were accrued from June 2008 through August 2008. Cohort C: Is still open with 16 pts accrued from August 2008 through December 5, 2008. Results: Median age 51: range 38 to 78. Cohort A: 29/38 pts completed 8 cycles of CMF. The regimen was considered feasible. 2 other pts completed 7 cycles and were withdrawn for depression and grade 2 transaminitis. The 7 other pts completed between 1 and 6 cycles of CMF were withdrawn as follows: 3 personal, 1 (grade 3) bone pain, 2 allergy unrelated to CMF, and 1 seizure. Cohort B: 7 pts were accrued. 6 out of 7 pts could not complete 8 cycles of chemotherapy secondary to neutropenia and 1 secondary to grade 3 ALT elevation. Cohort C: Accrual has not been completed. 16 pts are currently enrolled. Conclusions: Dose dense adjuvant CMF is feasible at 14 d intervals with PEG-filgrastim support. Adjuvant CMF every 10–11 days with filgrastim given for 5 days beginning day 2 is not feasible. Accrual is ongoing for CMF at 10–11 days with filgrastim x 7 days. Updated results will be available for Cohort C. [Table: see text]

Abstract Abstract 2638 Poster Board II-614 Background: The importance of cytogenetics in prognosis of AML is now widely recognized and accepted in clinical practice. A recent study found that autosomal chromosomal monosomy predicted for an adverse outcome. The goal of this study is to characterize patients with monosomal karyotype by mutation status and clinical features. Methods: One-hundred forty consecutive AML patients diagnosed at Stanford University Hospital between 2005 and 2008 with adequate material for mutation analysis were studied. Cases were classified using the 2008 WHO criteria. Diagnostic cytogenetic findings were reviewed and patients were stratified into risk groups using Southwest Oncology Group criteria. An abnormality was considered clonal when at least two metaphases had the same aberration, except for clonal monosomy, which required at least three metaphases. The karyotype analysis was based on 20 or more metaphases. All samples were tested for NPM, FLT3 (ITD and D835) and CEBPA mutations. Clinical parameters including hemogram data at time of diagnosis were reviewed. Clinical follow-up including overall survival (OS), progression free survival (PFS) and complete remission (CR) rates were retrospectively determined. Kaplan-Meier methods and univariate Cox proportional hazards regression analysis were used to compare the clinical data. Results: The cases included 77 males and 63 females with a median age of 58 (range 17-83). Cytogenetic risk-group stratification resulted in 14 patients with favorable, 88 with intermediate and 28 with unfavorable risk status. Loss of one or more autosomal chromosomes was present in 18 /130 patients (13.8%) with available cytogenetic studies. A single autosomal monosomy was found in 5 patients while 13 patients had two or more autosomal monosomies. The most common chromosomes lost in these 18 patients included 7 (55% of 18 cases), 5 (50%), 17 (33%), 21 (22%), 20 (22%), 22 (17%) and 18 (11%). Using the 2008 WHO criteria, there were 66 AML with myelodysplasia-related changes (AML-MRC), 55 AML not otherwise specified (AML-NOS), 14 AML with either t(8;21), inv(16) or t(15;17) and 5 therapy related AMLs. Overall, 35 patients (25% of all patients) had a NPM1 mutation (19 of which were FLT3 mutated), 33 had FLT3-ITD mutation (24%), 11 had FLT3-D835 (8%) and 11 had a CEBPA mutation (8%) (4 of which were FLT3 mutated). Patients with monosomal karyotype were significantly older (83 vs. 59 years, p=0.0125) and presented with lower WBC (34 vs. 66 K/uL, p=0.0006), lower platelets (41 vs. 64 K/uL, p=0.0111), and lower blasts (38% vs. 65%, p=0.0030) as compared to the rest of AML patients. In addition, patients with monosomal karyotype were more frequently diagnosed with AML-MRC (16/18 vs. 48/107, p=0.0034) and exhibited a decreased frequency of NPM1 mutation (0/18 vs. 28/107, p=0.0138) and FLT3-ITD mutation (0/18 vs. 29/107, p=0.0117). Clinical outcome data showed that patients with monosomal karyotype had a significantly worse OS, PFS and CR compared to the rest of AML patients (OS p=0.001, PFS p=0.002 and CR p=0.0262). Dividing patients by number of monosomies showed that patients with 2 or more monosomies had a significantly worse OS (p=0.0001) and PFS (p=0.0045) than patients without any monosomies. However, no difference in OS or PFS was seen when comparing patients with 1 monosomy to those with 2 or more monosomies. Within the AML-MRC group, monosomal karyotype correlated with lower WBC (17 vs. 37 K/uL, p=0.0005), lower platelets (21 vs. 35 K/uL, p=0.0095), lower blasts (19% vs. 36%, p=0.0015) and shorter OS (p=0.0322) and PFS (p=0.0084). Conclusion: AML patients with monosomal karyotype exhibit a significantly worse OS, PFS and lower CR as compared to other AML patients. Most of patients fall within the newly defined AML-MRC group and are characterized by significant absence of NPM1 and FLT3-ITD mutations. Disclosures: No relevant conflicts of interest to declare.

Abstract Background: Hematopoietic stem cell release is regulated by the sympathetic nervous system through the β (3) adrenergic receptor [Mendez-Ferrer et al. Nature 2008]. Peripheral sympathetic nerve neurons express the G-CSF receptor and stimulation of peripheral sympathetic nerve neurons with G-CSF reduced norepinephrine (NE) reuptake significantly, suggesting that G-CSF potentiates the sympathetic tone by increasing NE availability [Lucas et al Blood 2012]. Based on preclinical data, we investigated the NE reuptake inhibitor desipramine in HSC mobilization. Despite augmentation with Plerixafor (CXCR4 inhibitor), 20% of all patients fail to mobilize 6*10^6 CD34 cells/kg in myeloma and the collection rate with G-CSF alone is 51.1% [Diperiso et al Blood 2012]. The cost of upfront plerixafor is $9,081 per patient while desipramine costs $40. We undertook a feasibility study of adult patients with MM undergoing autologous transplantation (ASCT) to study safety and efficacy of mobilization with desipramine and G-CSF. Patients & Methods: From 2013- 2014, 10 patients between the ages of 18-70, eligible for ASCT were enrolled. Desipramine 100mg daily was administered for 7 days, starting 4 days prior to starting G-CSF (D-3) and continue along with G-CSF for a total of 7 days. CBC and CD34 counts were determined on Day+5. If CD34 counts were > 10/ul, stem cell collection was commenced and if < 10/ul, plerixafor was added as salvage therapy. The endpoints were safety and efficacy in mobilizing CD34 cells for ASCT in patients with multiple myeloma. This trial was registered at clinicaltrials.gov as NCT01899326. Results Six of ten patients enrolled completed the protocol and underwent stem cell transplantation. Reasons for not completing were 1. Lack of insurance coverage 2. Non-compliance with study treatment 3. Disease relapse prior to ASCT. Five patients did not have any grade 3 or 4 adverse events and 1 had disease-related Grade 4 hypercalcemia and Grade 2 AKI at the time of stem cell mobilization. No patients had significant treatment related adverse effects. All 6 patients who completed the protocol achieved the target collection of 5*10^6 CD34 cells/kg. Four patients achieved 6*10^6 CD34 cells/kg or more and the remaining 2 patients achieved 5.52 and 5.92 *10^6 CD34 cells/kg respectively. Among the 6 patients, 2 patients received salvage plerixafor. The median time to achieve WBC >1000/ul, ANC >500/ul and platelets>20k was 11.5, 11, 13.5 days Table 1. Age Ind. Regimne Disease status P PB CD34/ul CD34 collected *10^6 / kg Total CD34/kg collected Engraftment (Days to) Adverse effects from desipramine D1 D2 D3 D4 D2 D3 D4 ANC >0.5 Platelets> 20k G1,G2 G3,G4 1 62 Free λ VRD VGPR N 45.8 66.0 7.01 7.01 12 13 none none 2 50 Free λ VRD VGPR N 88.0 143.5 12.22 12.22 12 12 none none 3 58 IgA VCD VGPR N 38.0 67.7 31.6 4.22 2.75 6.97 13 17 none none 4 70 IgAκ VRD VGPR Y 2.40 40.2 16.6 4.31 1.61 5.92 12 14 none none 5 56 IgGκ VCD VGPR Y 8.70 11.9 37.1 19.4 1.33 4.57 1.61 7.51 11 12 none none 6 70 IgGλ VD RD Relapse N 76.2 97.1 5.54 5.54 11 20 AKI hypercalcemia P-Plerixafor; V-Velcade; R-Lenalidomide; D-Dexamethasone; C-Cyclophosphamide Conclusions Overall G-CSF + Desipramine combination appears to be safe, well tolerated and shows signs of efficacy. G-CSF and desipramine was successful in 4/6 (66%) and all achieved the stem cell collection in 2 days or less. Desipramine, GCSF and Plerixafor was successful in all (6/6) patients to achieve a target of 5*10^6 CD34 cells/kg. The mean number of CD34 cells collected in the desipramine+ G-CSF mobilisers was 7.24*10^6 CD34 cells/kg which, based on historical data, is higher than what would be expected with G-CSF alone even though 3/4 of these patients had lenalidomide as induction therapy. Based on these results, a phase II clinical study evaluating the efficacy of G-CSF with desipramine with or without salvage plerixafor in multiple myeloma and lymphoma will be initiated. Disclosures Barta: Seattle Genetics: Research Funding.

Abstract Background: Severe acute pancreatitis (SAP) frequently progresses to pancreatitis-associated multiorgan failure (MOF) with high mortality. Decreased plasma ADAMTS13 activity (ADAMTS13:AC) results in the accumulation of unusually large von Willebrand factor multimers (UL-VWFM) and the formation of platelet thrombi, ultimately leading to MOF. We demonstrated that the imbalance between decreased ADAMTS13:AC and increased UL-VWFM could contribute to SAP pathogenesis through enhanced thrombogenesis, and serve as an early prognostic indicator for SAP patients (Scand J Gastroenterol, 2008, 26:1). Endotoxin has been considered to be the principle activator of the systemic inflammatory response syndrome, which predisposes patients for MOF and/or pancreatic necrosis, ultimately leading to SAP. We investigated the relationship of endotoxin to ADAMTS13:AC and its related parameters, and tried to explore their potential role on the development of MOF in patients with SAP. Methods: We sequentially determined plasma endotoxin concentration, ADAMTS13:AC and its related parameters in 13 SAP patients (APACHE-II score mean 6.6 ± 2.7), who were admitted into intensive care unit of our hospital between 2004 and 2006. Eleven patients were survivors and two were non-survivors whose APACHE II scores were 10 and 12 died of MOF, respectively. The degree of MOF was evaluated according to the SOFA score. Endotoxin concentration was determined by a chromogenic substrate assay (Toxicolor LS –M Set, Seikagaku Kogyo Co.) with kinetic analysis after pretreatment with detergent, Triton X-100, and heating at 70 °C for 10 min. Plasma ADAMTS13:AC was determined by a sensitive chromogenic ELISA (ADAMTS13-act-ELISA: Kainos Inc.). Plasma UL-VWFM was analyzed by a vertical SDS-1.0% agarose gel electrophoresis. Plasma VWF antigen (VWF:AG), interleukin 6 (IL-6), interleukin 8 (IL-8), and tumor necrosis factor -α (TNF-α) were measured by ELISA. Results: In normal healthy controls (n=20), plasma endotoxin concentration was 7.9±1.7 pg/ml (mean ± SD). The concentration in the SAP patients significantly increased at day 1 (means 65 pg/ml, p<0.001) and at day 2 (88 pg/ml, p<0.001) as compared to healthy controls. The values, thereafter, gradually decreased in 8 survivors (55 pg/ml at day 5, 53 pg/ml at day 7, 27 pg/ml at day 14), while in remaining 3 survivors needing necrosectomy, the concentration further increased (98 pg/ml at day 5, 178 pg/ml at day 7), and decreased to 20 pg/ml at day 14 at the recovery phase. In two non-survivors, the endotoxin levels increased from 37 pg/ml at day 1 to 462 pg/ml at day 2 in one needing necrosectomy, and showed 51 pg/ml at day 1 in another at the age of 91. Within 1 or 2 days after admission, the ADAMTS13:AC was lower in SAP patients (mean 29%, p<0.001) than in healthy controls (99%), and gradually recovered in the 11 survivors but further decreased in the 2 non-survivors. On admission, VWF:Ag was higher (402%, p<0.001) in SAP patients than controls (100%). VWF:Ag gradually decreased in the survivors, except in the 3 survivors needing a necrosectomy, but remained high in the non-survivors. UL-VWFM positive patients showed lower ADAMTS13:AC (25% vs. 42%, p<0.05) and higher VWF:Ag ( 481% vs. 332%, p<0.05), resulting in higher ratio of VWF:Ag to ADAMTS13:AC (25.2 vs. 9.1, p<0.02), as compared to UL-VWFM negative ones. Patients with higher endotoxin concentration more than 50 pg/ml showed lower ADAMTS13:AC than those without (22% vs. 43%, p<0.05). Plasma endotoxin concentration positively correlated with the ratio of VWF:Ag to ADAMTS13:AC (r=0.732, p<0.005). The SOFA score correlated positively with plasma endotoxin concentration (r=0.604, p<0.03), IL-8 (r=0.843, p<0.001), and the ratio of VWF:Ag to ADAMTS13:AC (r=0.700, p<0.01), and inversely with the ADAMTS13:AC (r= − 0.601, p<0.03). Conclusion. The imbalance between decreased ADAMTS13:AC and increased UL-VWFM is closely related to enhanced endotoxemia, which may contribute to the development of SAP and subsequent MOF through enhanced thrombogenesis.

569 Background: Chemotherapy-induced splenomegaly is a relatively known treatment complication, where the clinical sequale of hypersplenism is persistent thrombocytopenia due to splenic sequestration. For cancer patients (pts) undergoing chemotherapy, thrombocytopenia may result in a dose delay or dose reduction, thus reducing dose intensity. The impact of refinement in technique with limited volume embolization (50-70%) of the spleen upon morbidity and mortality has not been well studied. Methods: A retrospective review of gastrointestinal cancer pts undergoing PSE for thrombocytopenia to facilitate the initiation or resumption of systemic chemotherapy between Jan. 2008 and March 2011 was completed. Pre- and post-PSE platelet (plt) counts within 30 days were evaluated for benefit of treatment. Objectives included the re-initiation of systemic therapy and post-PSE plt count >150 (< 30 days). Periprocedural laboratory values and adverse events were recorded. Results: PSE was performed in 79 pts. Median prior chemotherapy regimens = 2 (range 1-3). The median follow-up was 12M (range: 7-31). The mean plt count prior to PSE was 80 K/ UL (3-196). Post-PSE platelet count of > 150 was achieved in 52 (66%) pts with a mean peak plt count of 219 K/UL. Six (8%) pts underwent repeat PSE due to recurrent thrombocytopenia after initiation of systemic therapy. Re-initiation of chemotherapy was achieved in 59 (79%) pts. The median duration of chemotherapy following PSE was 8M (95% CI: 4.2-14.2); median overall survival was 33M (95% CI: 10-47). Post-procedure fever developed in 7 (9%) pts and pleural effusion, atelectasis, or consolidation was reported in 8 (10%) pts. Seventeen (21%) pts developed reversible grade 1 hyperbilirubinemia. Median length of hospital stay was 3 days (interquartile range 1-5 days). 60-day mortality rate was 9% (7 of 79). Conclusions: Partial splenic embolization (PSE) is a safe and effective method of managing thrombocytopenia secondary to chemotherapy-induced hypersplenism to facilitate re-initiation of systemic therapy in cancer patients. PSE may be considered as a potential option in patients with good performance status to facilitate further systemic chemotherapy.

Abstract Abstract 2234 Introduction/Background: Immunosuppressive therapy is the best alternative for patients with severe aplastic anemia (SAA) without matched sibling donor or with age > 40 years. Since 1988, an alternative protocol was developed with cyclosporine (CSA) and prednisone (PRED) due to irregularity in distribution of anti-thymocyte globulin (ATG) in Brazil. This study aims to show the results of this treatment on the quality of response, overall survival and development of clonal evolution. Materials and methods: 384 patients diagnosed with SAA (Camitta and Bacigalupo criteria) were evaluable by medical records review from 12/1988 to 12/2008. The immunosuppressive therapy consisted of CSA: 12mg/kg/day BID from day (D)1- D8, then 7mg/kg/day BID until 1 year. After that CSA was progressively tapered (5% each month) and ultimately stopped usually by two years. CSA levels were kept between 200–400ng/ml. PRED: 2mg/kg/day from D1-D14 then 1mg/kg/day from D15- D45. From that day on PRED dose was tapered 20% each week. Sulfamethoxazole-trimethoprim and fluconazole were used for prophylaxis against Pneumocystis jiroveci (P carinni) and fungal diseases, respectively. Treatment response was defined as Table 1. Treatment evaluation was performed at 6 weeks, 3, 6 and 12 months and then yearly. At diagnosis: median age was 21 years (2-75), disease duration 95 days (2-4749), and median number of transfusions were 12 (0-200). Etiology was idiopathic in 78%. In peripheral blood, median hemoglobin was 7.4g/dL, granulocytes 580/uL, platelets 12.000/uL and reticulocyte 0.5% (corrected value). 60% of the patients had not been treated previously. Results: Overall survival was 61% ± 3 with a median follow-up of 7 years (range: 2 months - 23 years). Response to treatment: 51% had some degree of response, with good quality of life and transfusions independent (143 patients with complete response and 53 partial response). 36 patients had no response and there were 96 deaths. Fifty six patients have lost follow-up. Most patients achieved response between 3 and 6 months of therapy. In multivariate analysis the number of neutrophils ≥ 200/uL (p = 0.009), platelets ≥ 12.000/uL (p = 0.018), reticulocyte ≥ 0.5% (p <0.001) and starting treatment after 1997 (p = 0.002) had an impact on overall survival. Patients with 15 or more previous transfusions (p = 0.006) and age ≥ 40 years (p = 0.003) had lower survival. Overall survival was 63% ± 4 and 42% ± 6 for for patients with severe disease and very severe aplastic anemia (p <0.001). The subgroup analysis of patients under 10 years old had similar results. Among patients with response, thirty-four remained dependent of CSA. Cumulative incidence of relapse was 28% ± 4 within a median of 4.4 years. Hypertension, gingival hypertrophy and diabetes mellitus were common, but easily controlled. The rate of clonal evolution among this cohort was 7.81% (16 patients developed Paroxysmal Nocturnal Hemoglobinuria, 9 Myelodysplastic Syndrome and 5 Acute Myeloid Leukemia). Conclusion: This study, with a long follow-up, has demonstrated that the overall survival using CSA and PRED is similar to that reported with ATG therapy. Even patients with partial responses had achieved good quality of life, free from transfusions and infections. Survival was influenced by the neutrophils, platelet counts, reticulocyte, number of transfusions, age at diagnosis, and therapy started after 1997. The incidence of clonal evolution was lower when compared to reported trials with ATG + CSA. Disclosures: Oliveira: Alexion: Speakers Bureau. Funke: Novartis, Bristol: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Pasquini: Novartis, Bristol: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Abstract Abstract 1588 Background: EBV-positive diffuse large B-cell lymphoma (EBV+ DLBCL) of the elderly is a provisional entity included in the 2008 WHO Classification of Lymphomas. Diagnostic criteria include age >50 years, DLBCL morphology and EBV expression in lymphomatous cells. However, these criteria are evolving as several patients are <50 years and a specific cut-off for the percentage of EBV expression has not been defined. The goal of this retrospective study is to evaluate clinical and pathological characteristics of EBV+ DLBCL from Peruvian patients. Methods: Between January 2002 and January 2012, all patients meeting criteria for EBV+ DLBCL were included in the analysis. Patients with evidence of immunosuppression were excluded. All cases re positive for the presence of EBV-encoded RNA (EBER) by in situ hybridization, and CD20 and/or PAX-5 expression by immuno-histochemistry. Clinical data were reviewed retrospectively and patient's biopsies were analyzed for the expression of BCL6, CD10, CD30 and MUM-1/IRF4 using a tissue microarray (TMA) technique. The overall survival (OS) curves were calculated using the Kaplan-Meier method, and compared using the log-rank test. Results: A total of 43 EBV+ DLBCL patients are included in this study. The median age was 73 years (range 25–95 years). Four patients (9% ) were <50 years. The male:female ratio was 2.2:1. B symptoms occurred in 59%, ECOG >21 in 60%, advanced stage (III/IV) in 58%, elevated LDH levels in 44%, and lymphocyte count <1000/uL in 35%. The International Prognostic Index (IPI) score was 0–2 in 39% and 3–5 in 61% of the patients. Extranodal disease occurred in 20 patients (46%): stomach (n=3), tonsil (n=3), pleura (n=2), palate (n=2), cecum (n=2), bone marrow (n=2), ileum (n=1), bone (n=1), skin (n=1), lung (n=1), meninges (n=1), breast (n=1) and peritoneum (n=1). Three patients had central nervous system involvement (7%), one at presentation and two at relapse. Based on the Hans classification, 76% had non-germinal center profile. Ki67 expression was >80% in 53% of the patients. Eleven evaluated patients had a c-myc-negative status. Chemotherapy was received in 75% of the cases due to poor performance status. The overall response rate with conventional chemotherapy was 46%, with complete response in 39%, partial response in 7%, and no response in 54%. The median survival was 7.5 months. The Oyama score was: 0 factors (13%), 1 factor (47%), and 2 factors (40%) with median OS of 41, 11 and 1.5 months respectively (p=0.07). A lymphocyte count <1000/uL was a prognostic factor for OS (p=0.001). Conclusions: Based on our study, which is the largest cohort in Latin-America, EBV+ DLBCL is an aggressive entity with frequent extranodal disease and poor response to conventional chemotherapy. The overall survival remains poor. Lymphopenia, as defined as lymphocyte count <1000/uL, appears as a prognostic factor for OS. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 4443 Introduction: Various chemotherapeutic agents particularly cyclophosphamide (CY) are utilized in combination with growth factors in an attempt to increase the number of stem cells available for collection in the peripheral blood. Plerixafor (P) is a reversible antagonist of CXCR4 and interrupts its interaction with SDF-1. This results in a rapid release of hematopoietic stem cells from the marrow to the circulation. Recent pivotal phase III trial data has established the efficacy of P in combination with G-CSF (G) in patients who had failed prior attempts at stem cell collection. However, there is limited data about the utility of plerixafor in patients who are being mobilized with chemotherapy and G. Method: In this single institution study of uniformly treated patients we describe our experience with the use of P as a salvage option in patients who fail to optimally mobilize CD34+ cells (>5 × 106 CD34+ cells/kg). Patients received CY (3-4 g/m2) followed by GCSF (10 mcg/kg) from day 1 to day 10. Thirteen patients (6 NHL, 4 MM, 2 Hodgkin lymphoma, 1 Ewings sarcoma) received salvage P from 2008–2010. Their outcomes were compared with 10 matched, historic controls mobilized with (CY n=8; CY + etoposide n=1; CY + topotecan n=1) plus G-CSF (10mcg/kg/d) identified from our institutional database. Data was collected on mobilization and transplant outcomes and analyzed utilizing SPSS version 13.0. Patients receiving P were closely matched to historic controls (CY+G). Result: Both groups were similar with regards to age, gender, disease type, prior therapies and performance status (p>0.05 for all). Patients in the P arm received a median of 2.5 doses (range 1–8). The mean CD34+ count was 21.5cells/ul in the P arm and 32.5 cells/ul in the CY+G arm (p=0.2). Similarly, no significant difference was observed in the average number of apheresis sessions in the P vs. CY+G arms (4.2 vs. 4.4, p=0.8) or the total number of CD34+ stem cells collected (4.0×106/kg vs. 3.9×106/kg, p=0.9). However, 7 out of the 13 patients who received P did have an increase of >10 CD34+ cells/ul in their peripheral blood. Utilizing a cut-off of 5×106 CD34+/kg, 3 (23%) patients in the P arm and 3 (30%) patients in the CY+G arm had a successful harvest. Three NHL patients required >4 doses of P, but all eventually collected >2 × 106 CD34+ cells/kg. Neutrophil and platelet engraftment dynamics were similar in both groups of patients. Median time to neutrophil engraftment was 10 days for both groups, p=0.8, and to platelet engraftment was 22 days vs. 20.5 days, p=0.1, respectively for P vs. CY+G. Conclusion: Our limited single-center retrospective case-controlled outcomes data, suggests that when compared with CY+G, the addition of P as a salvage agent does not significantly improve mobilization outcomes. Further evaluation is needed to combine P with CY+G in terms of optimal timing and potentially dosing of chemotherapy agents utilized. We suggest that the combination P+G would provide better potential outcomes such as improved collection and less hospitalization and reduce the use of chemo-mobilization prior to an Autologous Hematopoietic Stem Cell Transplant. Disclosures: No relevant conflicts of interest to declare.