Citations

Abstract Abstract 2818 Background: Pegylated interferon alpha-2a (Peg INF2a) has been demonstrated to be active therapy for high-risk essential thrombocythemia (ET) and polycythemia vera (PV), as well as treatment for early myelofibrosis (MF). We retrospectively analyzed the outcomes of Peg INF2a therapy in MPN patients treated outside the constraints of a clinical trial in the USA and EU. Methods: Clinical records of MPN patients treated at the participating centers, receiving Peg INF2a outside of the context of a clinical trial, were analyzed for response (ET and PV by ELN criteria; MF by EUNMET and IWG-MRT criteria), toxicity, and duration of response. Results: Patients: 115 patients were identified (54 PV (47%), 44 ET (38%), 17 MF (15%)) with a median age at diagnosis (48) and gender distribution (59% females) typical for the disorders. The patients had been diagnosed with the MPN a median of 44 months (0.0–312 months) prior to initiation of the Peg IFN2a and 64% harbored the JAK2-V617F mutation. The majority of patients (81%) had received at least one prior cytoreductive therapy for their disease (73 hydroxyurea, 39 anagrelide, 37 aspirin, 21 prior interferon (non pegylated), 3 phlebotomy alone). Therapy: Median starting dose of Peg INF2a was 45 micrograms/week (range: 22.5–180) with peak starting doses ranging from 30 to 300 micrograms/week. A total of 84 patients (73%) remain on Peg IFN2a with median duration of treatment of 17 months (range: 1.0–92). Toxicity: Overall the Peg INF2a was well tolerated. Hematological toxicity was Gr 3 or lower. There were 6 cases with anemia (5%), 10 with thrombocytopenia (9%) and 8 had leukopenia (7%). Most common non-hematologic toxicities were Gr 1–3 fatigue in 27 (23%), Gr 1 LFT elevation in 6 (5%), Gr 2–3 skin/allergic reaction in 6 (5%), Gr 1–2 nausea in 5 (4%), and Gr 2 mood disorder in 5 (4%) patients. Twenty patients (17%) discontinued therapy secondary to toxicity. Response: ET-PV: By ELN criteria, 30 PV patients achieved CR (55%), 17 achieved PR (31%), 4 achieved NR (7%), and 3 patients (5%) were lost to follow up or were too early to evaluate for response. In ET, the responses were CR in 27 (61%), PR in 7 (16%), NR in 4 (9%), and 6 patients (14%) were lost to follow up or were too early to evaluate for response. MF: The responses by IWG criteria were 1 CR (6%), 2 PR (12%), 2 CI (12%) and 9 SD (53%). By EUNMET, there were 2 CR (12%), 4 major responses (24%), 4 moderate responses (24%), 1 minor response (6%), 2 no response (12%), and 3 patients (17%) were lost to follow up or were too early to evaluate for response. Conclusions: Peg INF2a used at doses consistent with published clinical trials is active and well-tolerated when administered in a clinical setting outside of the support of a clinical trial. Given the majority of patients had previously failed cytoreductive therapy these results substantiate prior reports of efficacy of Peg INF2a in MPNs. Upcoming randomized clinical trials through the Myeloproliferative Disorders Research Consortium will help further define the role of Peg INF2a as first line therapy in high-risk MPNs. Disclosures: Mesa: Incyte: Research Funding; Lilly: Research Funding; SBio: Research Funding; Astra Zeneca: Research Funding; NS Pharma: Research Funding; Celgene: Research Funding.

A favorable prognosis and a low rate of leukemic transformation has been attributed to the 5q- syndrome, a myelodysplastic syndrome (MDS) characterized by macrocytic anemia, hypolobulated micromegakaryocytic hyperplasia, and an interstitial deletion of chromosome 5. We examined the characteristics and outcome of 43 consecutive patients in our institution strictly defined by morphologic criteria and a solitary 5q- cytogenetic defect. The median age at diagnosis was 68 years, with a clear female predominance (7:3). Eighty percent of the patients were red blood cell transfusion-dependent at diagnosis and all untransfused patients had macrocytic indexes. In contrast, significant neutropenia or thrombocytopenia was rare. The French-American-British (FAB) class distributions were RA (72%), RARS (7%), RAEB (16%), and RAEB-IT (5%). At a median follow-up of 31 months, 56% of the patients survive, with a projected median survival of 63 months. The incidence of acute leukemia was 16% and was uniformly fatal. Clinical hemosiderosis occurred in 28% of the patients, resulting in two deaths. Neither survival nor the risk of leukemic transformation was predictable from initial clinical parameters, including FAB classification, Bournemouth score, and degree of aneuploidy. The lack of significant neutropenia and thrombocytopenia seemed to account for a very low incidence of infection and bleeding resulting in a prognosis equal or superior to historical patients with MDS. Therapeutic endeavors, including the use of corticosteroids, androgens, cis-retinoic acid, pyridoxine, and danazol, were largely unsuccessful.

Abstract Abstract 4094 Background: Our group has previously reported the benefits of thalidomide-prednisone based regimens for improvement of anemia, thrombocytopenia, and splenomegaly for patients with MF; both primary myelofibrosis (PMF), and arising from essential thrombocythemia and polycythemia (Post ET/PV MF). We sought to evaluate the overall efficacy of these commonly used regimens by evaluating long-term outcomes and applying the IWG-MRT response criteria (Tefferi et. al. Blood 2006) which arose after completion of these trials. Methods: We retrospectively analyzed the long-term outcomes, and assessed the initial therapeutic responses using IWG-MRT criteria from three parallel completed trials of MF using a thalidomide (THAL-50 mg/day) and prednisone (3 month taper beginning at 40mg, stopped at 3 months) backbone. The trials had identical eligibility criteria including adequate organ function and need for MF therapy (defined as symptomatic: anemia and/or splenomegaly). The trials were 1) THAL-PRED alone, THAL only after 3 months 2) THAL-PRED-etanercept (ETAN - TNF- alpha inhibitor at 25 micrograms subcutaneously twice a week), THAL and ETAN only after 3 months and 3) THAL-PRED – oral cyclophosphamide (CTX 25mg daily orally), THAL alone after 3 months. Results: Patients: A total of 50 pts were enrolled in these 3 trials (Males n=36, 72%) with median age of 68.5 years (Range 43–85), with 79% having PMF. Patients had advanced disease in general with 88% having intermediate 2 or high risk MF by IWG criteria (Cervantes et. al. Blood 2009), 62% patients with red cell transfusion dependence and 50% with an abnormal karyotype. Therapy initial results: 80 % of patients reached the three month juncture on the trials, with 40% reaching 6 months. Initial toxicity was myelosuppression with 3 cases of grade 3 anemia, 3 cases of grade 3 neutropenia and 4 cases of grade 3 thrombocytopenia. There were no grade 4 or higher hematological toxicities noted. Initial neuropathy was uncommon and seen in only 4% of patients. No complete responses were observed and only 1 patient had partial response (by IWG-MRT criteria). 14 patients (28% overall) met the new IWG-MRT criteria for clinical improvement; 11 for anemia (22%), 2 for thrombocytopenia (4%) and 3 for splenomegaly (6%). Responses occurred relatively quickly at an overall median of 8 weeks (range 4–12) after enrollment. Long Term Outcomes: After a median follow-up of 36 months across this cohort we observed an overall median duration of response of 8.5 months (range 3–42). Responses to THAL based regimens can lead to periods of prolonged stabilization after cessation of therapy. We observed an overall median time to institution of next therapy of 3 months (range 1–50). At the time of this analysis 14 patients (28%) have expired of their MF and median survival across the entire cohort was 36 months (3-106). Comparison of Regimens: Comparison of these three independent trials (Table 1) suggests greater toxicity and inferior response rate, duration of response, and time to next therapy with the cyclophosphamide containing regimen. Conclusion: THAL-PRED based regimens are active in a subset of MF patients for therapy primarily of anemia, and for some patients a response of good duration (even after cessation of therapy) may be obtained. IWG-MRT response assessment demonstrates utilizing additional agents to a THAL-PRED regimen do not appear to augment (and may detract from responses). Newer agents such as pomalidomide may have similar to greater efficacy without neuropathy and less myelosuppression. Disclosures: Off Label Use: There is no FDA approved agent in Myelofibrosis. All the drugs discussed; Thalidomide, Prednisone, Etanarcept and Cyclophosphamide are off-label. Mesa:SBio: Research Funding; Novartis: Research Funding; Celgene: Research Funding; Incyte: Research Funding; Roche: Research Funding; eisai: Research Funding; telik: Research Funding.

Abstract Background Morbidity and mortality in tumor lysis syndrome (TLS) remains high despite increasing efforts for prevention, early detection and treatment in recent years. The current risk stratification system and treatment guidelines are largely consensus based without strong evidence. There is paucity of data on the in-hospital mortality and predictors of poor clinical outcome in this population. Methods We used the 2009-2011 Nationwide Inpatient Sample database to identify hospitalizations in patients ≥18 years with a diagnosis of TLS (International Classification of Diseases, 9th Revision, Clinical Modification [ICD-9-CM] code 277.88). Nationwide Inpatient Sample is the largest all-payer publicly available inpatient care database in the US. It contains data from five to eight million hospital stays from about 1,000 hospitals across the country and approximates a 20% sample of all US hospitals. The interval 2009-2011 was selected as ICD-9-CM code 277.88 for TLS was only introduced from the year 2009 onwards. Univariate and multivariate logistic regression were used to determine the independent predictors of in-hospital mortality. Data analysis was done using STATA version 13.0 (College Station, TX). Results Among the 997 admissions (mean age ± SD 67.58±3.33, 62.6 % males, and 80.4 % white) with TLS, in-hospital mortality was 14.44 %. Based on the results of univariate analyses (table 1), we used obesity, coronary artery disease, cardiac dysrhythmias, acute kidney injury and sepsis in the final regression model. We found that cardiac dysrhythmias (OR 4.79; 95% CI, 1.67-13.77; p=0.004) and sepsis (OR 19.70; 95% CI, 5.33-72.78; p<0.001) were independent predictors of increased in-hospital mortality in patients with TLS. Although certain myeloid and lymphoid malignancies are associated with higher risk of tumor lysis syndrome, we did not observe any statistically significant increased risk of mortality with one specific type of malignancy over the other. Similarly, none of the demographic characteristics (age <40 vs ≥40, sex or race), or hospital characteristics (rural vs urban, teaching vs non-teaching, small vs large bed-size or geographic region) predicted increased in-hospital mortality in these patients. Conclusion In this study of large national database, patients with TLS had an in-hospital mortality of 14.44 %. Independent predictors of in-hospital mortality were cardiac dysrhythmias and sepsis. Our findings might help physicians to identify sub-group of patients with TLS that are at increased risk of in-hospital mortality. Table 1 Baseline characteristics of patients with tumor lysis syndrome according to in-hospital survival Characteristics Survivors (n=853) Non-survivors (n=144) p Age( in years) Mean 68.40±3.06 67.58±3.33 0.73 Male sex 62.1 65.8 0.69 Race 0.16 White 81.52 73.54 Black 14.98 22.8 Hispanic 2.27 0 Others/unknown 1.22 3.66 Insurance status 0.41 Medicare 65.55 48.15 Medicaid 5.56 13.34 Private insurance 24.89 32.58 Self-Pay 0.65 2.99 No charge 0.63 0 Other 2.72 2.93 Region 0.13 Northeast 27.59 37.74 Midwest 28.23 12.92 South 31.34 39.9 West 12.84 9.44 Location/teaching status 0.59 Rural 7.87 10.16 Urban nonteaching 26.01 33.52 Urban teaching 66.12 56.32 Bed-size 0.84 Small 11.11 8.91 Medium 21.04 24.55 Large 67.85 66.54 Malignancies ALL 1.19 6.79 0.25 AML 2.34 6.99 0.29 CLL 27.86 16.83 0.18 CML 1.85 3.19 0.68 NHL 36.33 22.37 0.1 HD 0.53 0 0.32 Multiple Myeloma 7.39 6.56 0.82 Other hematologic malignancies 38.67 25.99 0.16 Solid tumors 35.87 26.8 0.32 Co-morbidities Smoking 15.89 21.87 0.46 Obesity 5.16 0 0.005 Dyslipidemia 27.8 16.86 0.18 Hypertension 54.17 49.19 0.63 Diabetes mellitus 27.81 16.65 0.15 PVD 1.71 3.19 0.65 CAD 13.78 3.19 0.02 AKI 60.06 79.54 0.03 CKD 28.81 25.23 0.65 Stroke 0.63 0 0.32 Sepsis 3.58 31.81 0.003 Cardiac dysrhythmias 17.96 43.42 0.04 Acute CHF 11.44 7.08 0.43 AKI=Acute Kidney Injury; ALL=Acute Lymphoblastic Leukemia; AML=Acute Myelogenous Leukemia; CAD=Coronary Artery Disease; CHF=Congestive Heart Failure; CKD=Chronic Kidney Disease; CLL=Chronic Lymphocytic Leukemia; CML=Chronic Myelogenous Leukemia; HD=Hodgkin Disease; NHL=Non Hodgkin Lymphoma; PVD=Peripheral Vascular Disease Disclosures No relevant conflicts of interest to declare.

Abstract Abstract 1184 Lenalidomide, a second generation immunomodulatory derivative of thalidomide, has demonstrated significant clinical benefit in myelodysplastic syndrome, multiple myeloma and B-cell malignancies. Its side effects include myelosuppression, particularly neutropenia, and impaired filgrastim induced stem cell mobilization in patients with myeloma. The precise mechanism of action of lenalidomide on hematopoietic and bone marrow microenvironment remains largely unknown. In this study, we investigated the effect of lenalidomide on survival, lineage commitment and differentiation of normal purified CD34+ hematopoietic stem cells. Mobilized peripheral blood progenitor cells (PBPCs) were obtained from a normal allogeneic stem cell donor with an informed consent, and were subjected to positive selection with the EasySep magnetic cell selection system to purify CD34+ cells (purity of 95%). Unsorted and CD34- accessory cells were used as controls. To assess the direct cytotoxic and proliferative effect of lenalidomide on purified CD34+ cells, lenalidomide (Celgene, NJ) was dissolved in DMSO and was diluted in culture medium to final concentration of 0.1, 1, 10, or 100 μM. Purified CD34+, CD34- and unsorted cells were plated in triplicates at a density of 2×104/mL in serum-free StemSpan® medium supplemented with growth factors and cytokines. 24 hours after plating the cells, lenalidomide or 0.1% DMSO as control was added. 72 hours following treatment, cells were counted with Beckman coulter counter and phenotypically analyzed using Accuri C6 flow-cytometer. The percentage of viable cells was determined using 7AAD staining. While no difference in viability was noted in the treated vs. untreated purified CD34+ cells, the viability of CD34- cells and unsorted cells was reduced to 30% and 40% respectively by lenalidomide. Contrary to our assumption, lenalidomide, in a dose dependant manner, induced proliferation of purified CD34+ cells. Maximal increase in proliferation was observed between 1mM and 10mM concentrations. The rate of growth plateaued beyond the 10mM concentration and 100mM concentration appeared to have no additional effect. At the peak of growth (10mM), the cell count nearly tripled. (Fig. 1) Lenalidomide appeared to be cytotoxic to CD34- and unsorted cells in a dose dependant manner. At 100mM concentration, the CD34- cell proliferation dropped by 4 fold and the unsorted cells by 7 fold. To examine the effect of lenalidomide on the clonogenic potential of purified CD34+ cells, 2,000 cells were seeded onto MethoCult® media (Stem cell technologies) supplemented with growth factors and cytokines. Cells were cultured in the presence of lenalidomide (0.1, 1, 10 and 100 μM) or 0.1 % DMSO as control. BFU-E, CFU-GM and CFU-mix were scored on day 14 with the use of an inverted microscope and standard morphological criteria. Significance of difference between groups was determined by student's t test for paired samples. Lenalidomide induced a significant increase in clonogenic activity of CD34+ cells (148 ± 27 colonies per 103 CD34+ cells, p = 0.01), most evident at the dose of 10 μM with enhanced formation of BFU-E (102 ± 23/ per 103 CD34+ cells, p = 0.01) but demonstrated no significant impact on CFU-GM (36 ± 14 per 103 CD34+ cells, p = 0.83) compared to control. (Fig. 2) This study demonstrates that lenalidomide has pronounced effects on both CD34+ and CD34- components of mobilized PBPCs. It enhances the proliferative and clonogenic potentials of CD34+ cells with lineage commitment towards erythroid differentiation. It also has cytotoxic activity towards CD34- cells. It is likely that neutropenia and impaired mobilization of stem cells in patients treated with lenalidomide is mediated via its impact on CD34- accessory cells in the bone marrow microenvironment. Further studies exploring the impact of lenalidomide on normal bone marrow stromal cells, T and NK cell mediated signaling are needed. Disclosures: No relevant conflicts of interest to declare.

Bleeding after cardiac surgery is a common and serious complication leading to transfusion of multiple blood products and resulting in increased morbidity and mortality. Despite the publication of numerous guidelines and consensus statements for patient blood management in cardiac surgery, research has revealed that adherence to these guidelines is poor, and as a result, a significant variability in patient transfusion practices among practitioners still remains. In addition, although utilization of point-of-care (POC) coagulation monitors and the use of novel therapeutic strategies for perioperative hemostasis, such as the use of coagulation factor concentrates, have increased significantly over the last decade, they are still not widely available in every institution. Therefore, despite continuous efforts, blood transfusion in cardiac surgery has only modestly declined over the last decade, remaining at ≥50% in high-risk patients. Given these limitations, and in response to new regulatory and legislature requirements, the Society of Cardiovascular Anesthesiologists (SCA) has formed the Blood Conservation in Cardiac Surgery Working Group to organize, summarize, and disseminate the available best-practice knowledge in patient blood management in cardiac surgery. The current publication includes the summary statements and algorithms designed by the working group, after collection and review of the existing guidelines, consensus statements, and recommendations for patient blood management practices in cardiac surgery patients. The overall goal is creating a dynamic resource of easily accessible educational material that will help to increase and improve compliance with the existing evidence-based best practices of patient blood management by cardiac surgery care teams.