Abstract: Background: MDSs are clonal hematopoietic stem cell malignancies characterized by cytopenias resulting from ineffective hematopoiesis. A phase 2 study of lenalidomide (MDS-002) demonstrated hematological improvement in patients with MDS without an associated deletion 5q cytogenetic abnormality (List AF, et al. Haematologica2006;91[suppl1]:379[abst 1032] ). We now report multicenter results after 〉2 yrs follow-up. Methods: A total of 214 pts with transfusion-dependent anemia were categorized into the following IPSS MDS risk groups after central review of bone marrow morphology, karyotype, and peripheral blood findings: Low/Int-1 (168 [78%]); Int-2/High (8 [4%] ); and unclassified (38 [18%]). Patients were unclassified for missing or inadequate marrow studies for central review (morphology [29] or cytogenetic [7]) or other diagnoses (AML [1] , atypical CML [1]). Patients were evaluated for frequency and duration of red blood cell transfusion independence (RBC-TI) (IWG criteria), hemoglobin (Hgb) response, and safety. The starting dose of lenalidomide was 10 mg (daily or daily × 3 wks q28d cycle). Results: Overall, 56 (26%) of 214 enrolled patients achieved RBC-TI. Median time to RBC-TI was 5 wks, median duration of RBC-TI response was 41.0 wks (range, 8.0–136.4), and median Hgb increase achieved during RBC-TI was 3.2 g/dL (range, 1.0–9.8). An additional 36 patients experienced a ≥ 50% reduction in RBC transfusions (overall hematological improvement in 92 [43%] patients). Overall, 47 (22%) patients had an abnormal karyotype at baseline and 9 (19%) patients achieved a cytogenetic response (4 complete). The most common drug-related grade 3/4 adverse events (AEs) were neutropenia and thrombocytopenia (25% and 20%, respectively). Deep vein thrombosis occurred in only 2 (1%) patients. The duration of RBC-TI was ≥ 52 weeks in 21 (38%) patients. Among these 21 patients, 14 (67%) did not require a lenalidomide dose reduction during the first 52 weeks of treatment. Analyses of response variables will be presented. Dose-limiting neutropenia/thrombocytopenia was not reported after 52 weeks. The most commonly reported AEs after 52 weeks were mild-moderate diarrhea and fatigue (38% and 29%, respectively). Conclusion: Lenalidomide is an active, well-tolerated treatment in MDS patients with transfusion-dependent anemia that is not associated with a deletion 5q abnormality. The rate of erythroid hematologic improvement and duration of RBC-TI is encouraging and offers a possible alternative to cytokine therapy.

Abstract: Anti-KEL alloantibodies generated after exposure to paternally derived RBC antigens during pregnancy result in fetal anemia. This is the first animal model of pregnancy associated HDFN, with transfusion and pregnancy resulting in boostable anti-KEL alloantibodies.

Abstract: Background: The indications for treating children with immune thrombocytopenia (ITP) remain controversial. A valid and reliable bleeding assessment tool could assist in objectively quantifying bleeding and influence treatment decisions. Both the ITP Bleeding Score (IBLS) and the ITP-Bleeding Assessment Tool (BAT) have been developed to assess bleeding severity in ITP. The IBLS scores bleeding severity using an 11-item tool with grading from 0 to 2 and the 18-item BAT grades from 0 to 3 or 4. The BAT includes some types of bleeding not represented on the IBLS, such has intramuscular hematomas. To date, no data describe how these two measures compare when measuring bleeding associated with ITP. Objective: To describe and compare bleeding as assessed by both the IBLS and BAT and to correlate bleeding severity with platelet counts in a cohort of children with ITP. Methods: A longitudinal observational cohort of children ages 〉 1 and 〈 18 years with ITP, were enrolled from 2013-2015 in the Pediatric ITP Consortium of North America ICON1 trial. All children were enrolled prior to starting a new second line monotherapy (not IVIG, steroids or anti-D). At enrollment, bleeding was assessed using the IBLS in all children. A subset of children also underwent a BAT assessment. Grades of bleeding were described and compared between tools and agreement in grading was assessed. Severity was correlated with platelet count using Spearman's correlation calculation. Results: 118 children were enrolled from 21 ICON centers. 54% had chronic ITP and the median age was 11.4y (range 1.2-17.8). The mean platelet count was 28 x 109/l (SD 57) and 88% had a baseline platelet count of 〈 30 x 109/l. The burden of skin and oral bleeding was high. Table 1 compares bleeding scores for the 78 patients with both measures. Agreement for grades 0, 1, and 2 between the measures was highest for urinary bleeding (97%), gastrointestinal (95%), subconjunctival (95%), and epistaxis (91%). Agreement between IBLS oral bleeding by historyand BAT gum bleeding was 78% and with BAT oral cavity bleeding was 79%. IBLS oral bleeding by physical examination and BAT gum bleeding was 73% and BAT oral cavity bleeding was 79%. The lowest agreement was seen for skin manifestations. IBLS skin bleeding by history showed only 54% and 62% agreement with the BAT ecchymoses and petechiae items respectively. IBLS skin bleeding by physical examination showed 59% agreement with both the BAT ecchymoses and petechiae items. Grades 3 and 4 scores from the BAT did not provide additional information beyond the IBLS for most sites of bleeding. For sites included on the BAT but not represented on the IBLS, only 1 child had an intramuscular hematoma, 1 suffered an ocular bleed, and none experienced hemarthrosis. Bleeding from minor wounds and bleeding with tooth loss captured additional bleeding symptoms in 9 and 4 children, respectively. There were no episodes of pulmonary or intracranial hemorrhage in the cohort. Table 2 shows the correlation between bleeding severity and platelet count for all items on each measure. Conclusion: The IBLS and BAT were similarly effective at identifying bleeding symptoms, although neither tool showed strong correlation with the platelet count. There were moderate correlations noted between skin bleeding scores and platelet counts for both tools. A major limitation of this comparison is the different definitions of bleeding severity between the two measures. For sites where the items were more detailed, agreement declined (i.e. adding specificity reduced generalizability). While no patients in our cohort exhibited significant grade 3 or 4 bleeding outside of skin findings, we conclude that in the setting of clinical trials, the ability to capture very severe bleeding might be an important distinction that supports using the more complicated BAT, but for clinical practice, a simplified assessment such as the IBLS may suffice. Disclosures Grace: Agios Pharmaceuticals: Other: Scientific Advisor, Research Funding. Neufeld:Novartis: Consultancy. Bussel:Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; UpToDate: Patents & Royalties; Protalex: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genzyme: Research Funding; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding; Symphogen: Membership on an entity's Board of Directors or advisory committees; Rigel Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Shionogi: Membership on an entity's Board of Directors or advisory committees; Sysmex: Research Funding; Momenta Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Immunomedics: Research Funding; Eisai: Membership on an entity's Board of Directors or advisory committees, Research Funding; Boehringer Ingelheim: Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Research Funding; Prophylix Pharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Physicians Education Resource: Speakers Bureau; BiologicTx: Research Funding. Haley:CSL Behring: Honoraria; Baxalta: Membership on an entity's Board of Directors or advisory committees. Thompson:Celgene: Research Funding; ApoPharma: Consultancy, Membership on an entity's Board of Directors or advisory committees; Mast: Research Funding; Amgen: Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Amgen: Research Funding; Baxalta (now part of Shire): Research Funding; bluebird bio: Consultancy, Research Funding; Baxalta (now part of Shire): Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; bluebird bio: Consultancy, Research Funding; Mast: Research Funding; ApoPharma: Consultancy, Membership on an entity's Board of Directors or advisory committees; Eli Lily: Research Funding; Eli Lily: Research Funding.

Abstract: Polycythemia Vera (PV) is a myeloproliferative neoplasm driven by activating mutations in JAK2 that result in unrestrained erythrocyte production, increasing patients' hematocrit and hemoglobin concentration, placing them at risk of life-threatening thrombotic events. Our GWAS of 440 PV cases and 403,351 controls utilizing UK Biobank data found that SNPs in HFE known to cause hemochromatosis are highly associated with PV diagnosis, linking iron regulation to PV. Analysis of the FinnGen dataset independently confirmed over-representation of homozygous HFE variants in PV patients. HFE influences the expression of hepcidin, the master regulator of systemic iron homeostasis. Through genetic dissection of PV mouse models, we show that the PV erythroid phenotype is directly linked to hepcidin expression: endogenous hepcidin upregulation alleviates erythroid disease whereas hepcidin ablation worsens it. Further, we demonstrate that in PV, hepcidin is not regulated by expanded erythropoiesis but is likely governed by inflammatory cytokines signaling via GP130 coupled receptors. These findings have important implications for understanding the pathophysiology of PV and offer new therapeutic strategies for this disease.

Abstract: We studied the prognostic significance of plasmablastic (PB) multiple myeloma (MM) in Eastern Cooperative Oncology Group Phase III trial E9486. Two reviewers independently reviewed 453 cases. They agreed on 37 PB (8.2%) cases and 416 non-PB cases, achieving an 85% concordance (P  〈  .0001). These PB cases had significantly lower hemoglobin and serum albumin levels, higher calcium and β 2-microglobuin levels, and higher percentage BM plasma cells (PC) by immunofluorescence. They had higher bone marrow PC labeling indices, higher serum soluble interleukin-6 receptor (sIL-6R) levels, and a higher probability of ras mutations. Three treatment regimens were used: vincristine, bis-chloro-ethyl nitrosourea (BCNU) melphalan, cyclophosphamide, and prednisone (VBMCP) alone; VBMCP with added cyclophosphamide (HiCy); or recombinant interferon α 2 (rIFNα2). Although the numbers are low, patients with PB had a significantly lower response rate versus non-PB MM when treated with VBMCP (treated, 47.1% v nontreated, 66.5% [P = .015]). Patients with nonresponding PB had a significantly higher progression rate than non-PB cases (30.6%v 11.8% [P  〈  .0001]), especially with VBMCP alone (35.3% v 15.8% [P = .002] ), and with added HiCy (37.5% v 9.8% [P  〈  .0001]), but not with added rIFNα2. Event-free and overall survival of PB MM was shorter (median years, 1.1 v 2.7 and 1.9 v 3.7, respectively [P  〈  .0001 for both]). In multivariate analysis, PB classification was also highly prognostic. There is no survival difference between the patients who were classified as PB by both reviewers versus patients classified as PB by only one reviewer. We conclude that PB MM is a discrete entity associated with more aggressive disease and shortened survival. Tumor cell rasmutations and increased sIL-6R may contribute to a higher proliferation rate and reduced survival. There were significant improvements in response and progression with the addition of HiCy and rIFNα2 to VBMCP, but the numbers were small and improved survival could not be shown.

Abstract: Background: Chronic immune thrombocytopenia (ITP) is a complex autoimmune disease characterized by antibody mediated platelet destruction and impaired production. Sustained autoimmunity in chronic ITP appears to be due to generalized immune dysregulation including altered T cell balance with a shift toward immune activation (increased Th1/Th2 ratio) as well as decreased number and impaired function of regulatory T cells (Treg). The cause of these abnormalities has not been fully elucidated and is likely multifactorial, but genetic factors may be involved in ITP pathogenesis. Improved understanding of genetic influences could lead to novel therapeutic approaches. Aim: To identify genetic variants that may be involved in chronic ITP susceptibility and severity. Methods: Whole exome sequencing (WES) was performed on 262 samples with robust phenotype data on children with chronic ITP from the North American Chronic ITP Registry (NACIR, n= 173) and the Platelet Disorders Center at the Weill-Cornell Medical Center (n=89). All but three patients were ≤19 years old at diagnosis; 83% had primary ITP, 10% had Evans syndrome, 7% had other autoimmune disorders. Sequencing data for ITP cases of European American (EA) ancestry were compared to EA controls with platelets 〉 150 x 109/L sequenced in the Atherosclerosis Risk in Communities (ARIC) Study (N=5664) to identify candidate genes associated with ITP susceptibility. Analyses filtered variants on a minor allele frequency (MAF) 〈 0.01 as well as functionality of nonsynonymous, stop gain, splicing, stop loss, and indel variants. Both Fisher-Exact tests of single variants and Firth logistic regression for gene-based tests, accounting for an unequal proportion of cases compared to controls, were used. A Bonferroni corrected threshold based on 16,532 genes was calculated at 3.0x10-6. In a separate analysis, phenotype data for ITP cases were reviewed and cases stratified by disease severity according to second line treatment needed (Yes =139, No=113) and compared to ARIC EA controls with platelet count 〉 150 x 109/L (N=5664). Results: Several damaging variants identified in genes involved in cellular immunity had a significantly increased frequency in the EA ITP cohort (Table). The most significant associations were detected in the IFNA17 gene, which is involved in TGF-β secretion and could affect number and function of the Treg compartment. IFNA17 rs9298814 (9:21227622 A 〉 C) was identified in 26% of cases in the EA ITP cohort compared to 〈 0.01% of EA controls, and other low frequency but presumed deleterious variants were also identified in IFNA17. IFNA17 gene variants remained significant in the most severely affected patients, specifically those requiring second line therapy, providing further evidence for this gene's functional relevance in the pathogenesis and pathophysiology of ITP. Other genes with known impact on T cell number or function, including DGCR14, SMAD2 and CD83 also contained variants with increased frequency in the EA ITP cohort. IFNLR1 and REL genes were also significantly associated with need for second line ITP therapy. Analysis of this large cohort did not validate any of over 20 variants that have been previously published as candidates for ITP susceptibility or evolution to chronic ITP. Conclusion: Damaging variants in genes associated with cellular immunity have an increased frequency in children with chronic ITP compared to controls, providing further evidence for the role of T cell abnormalities in the pathophysiology of ITP. The IFNA17 and IFNLR1 genes maintained significance when the ITP cohort was stratified according to disease severity, and may be important candidate genes involved in immune regulation and sustained autoimmunity associated with chronic ITP. Table. Genes identified through WES analysis of children with chronic ITP. Gene Function Relevant to ITP Pathophysiology Minor Allele Count (MAC)Cases Controls p value EA Chronic ITP vs. EA ARIC (non-ITP) controls N=172 N=5664 IFNA17 Treg, TGF-β signaling 91 17 3.97x10-13 DGCR14 IL-17 induction 14 3 1.27x10-10 SMAD2 TGF-β signaling 1 0 5.62x10-22 CD83 Th17/Treg balance 2 3 1.67x10-6 EA Chronic ITP requiring Second Line Therapy vs. EA ARIC (non-ITP) controls N=139 N=5664 IFNLR1 Class II cytokine receptor 2 1 3.95x10-15 IFNA17 Treg, TGF-β signaling 75 17 3.40x10-7 REL T and B cell function, inflammation 2 0 1.39x10-14 Disclosures Off Label Use: Off-label use of CliniMACS purified CD34+ cells. Lambert:GSK: Consultancy; NovoNordisk: Honoraria; Hardin Kundla McKeon & Poletto: Consultancy. Recht:Baxalta: Research Funding; Kedrion: Consultancy. Bussel:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; protalex: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; rigel: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract: Background: The impact of second line therapies on health related quality of life (HRQoL) and fatigue in pediatric patients with ITP is not well studied. Objective: To describe the impact of second line therapies on HRQoL and fatigue in North American pediatric patients with ITP. Methods: A longitudinal observational cohort of 120 children with ITP starting second line treatments was enrolled from 2013-2015 at 21 ICON centers. Enrollment requirements included age 1-17y and starting a second line treatment (not IVIG, corticosteroids or anti-D immunoglobulin) as monotherapy. HRQoL (Kids ITP Tool - KIT) and fatigue (Hockenberry Fatigue Scale - FS) surveys were completed prior to starting treatment (baseline) and 1 and 12 months after starting treatment by patient/caregiver. KIT is scored from 0 (worst) to 100 (best), and the FS scores were re-scaled so that 0 is no fatigue and 100 is highest fatigue. At the same time points as the patient/caregiver surveys, physicians assessed the perceived effect of treatment on patient HRQoL using a 7-point scale. ANOVA was used to compare the baseline means of the treatment groups. This study specifically compared change from baseline to 1 month in the KIT and FS using paired t-tests within each treatment group. The 12 month timepoint was not used in the paired analysis of individual treatments due to attrition between 1 and 12 months. Results: The median age at enrollment was 11.3 y (1.2-17.8), and 16% (19/120) had newly diagnosed ITP, 31% (37/120) had persistent ITP, and 53% (64/120) had chronic ITP. The median number of prior treatments was 3 (range: 1-9). Fifty-eight (48%) patients had received at least one prior second line treatment. Treatments selected for second line treatment included: rituximab (n=43), romiplostim (n=31), eltrombopag (n=20), oral immunosuppressants (n=19), splenectomy (n=4), and dapsone (n=3). The child and parent proxy KIT scores significantly improved on rituximab (p & lt;0.001 for both), oral immunosuppressants (p=0.02, p=0.001), and eltrombopag (p=0.01 for both). Child KIT scores also significantly improved on romiplostim (p=0.003); however, there was no significant change in the parent proxy score (p=0.29). The parent impact KIT scores significantly improved from baseline to 1 month on all treatments (p & lt;0.001), although the scores were not significantly different between treatment types (p=0.67). Child, parent proxy, and parent impact KIT scores significantly increased between 1 month and 12 months in paired analysis combining treatments (p & lt;0.001). As previously described, at enrollment, physicians reported that ITP had impacted the patients' HRQoL severely in 15%, significantly in 45%, moderately in 38%, and almost not at all in 3%. Physicians reported that HRQoL improved in 68% (range: 64-75%) of patients while on treatment from baseline to 1 month with no significant difference by treatment group (p=0.46). The physician's assessment of the patient's baseline HRQoL significantly correlated with the child and parent proxy KIT report (p & lt;0.0001); however, after 1 month of treatment, the physician's assessment no longer correlated with the child (p=0.26) or parent proxy KIT report (p=0.11). At enrollment, the median FS-Child score (n=54) was 18.5 (range 0-85), the median FS-Adolescent score (n=42) was 20.2 (0-73), and the median FS-Parent (n= 100) score was 35 (7-81). One month FS-Child improved for those who were treated with rituximab (p=0.03); there was no significant change in fatigue on the other treatments. One month FS-Parent significantly improved for those treated with rituximab (p=0.015) and eltrombopag (p=0.009). Conclusions: In this pediatric cohort, all second line treatments appear to significantly improve HRQoL in ITP. Rituximab had the greatest impact in decreasing fatigue at one month. Physician assessment of patient HRQoL did not correlate well with patient assessment after treatment was started, suggesting there may be challenges in ascertaining the effect of treatment on HRQoL. Future analysis of ICON1 will consider the impact of treatment on HRQoL and fatigue while also accounting for the treatment effect on bleeding and platelet count. Disclosures Grace: Agios: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Klaassen: Amgen: Consultancy; Hoffman-La Roche LTD: Consultancy; Octapharma: Honoraria; Baxalta: Honoraria; Biogen Canada LTD: Consultancy; Agios Pharmaceuticals: Consultancy. Despotovic: Sanofi: Consultancy; Schell Cooley LLP: Other: Expert witness. Bussel: Protalex: Membership on an entity's Board of Directors or advisory committees, Research Funding; Momenta: Membership on an entity's Board of Directors or advisory committees; Rigel: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Rothman: Pfizer: Consultancy; Agios Pharmaceuticals: Honoraria. Haley: Genentech: Honoraria; Baxalta: Honoraria; CSL Behring: Honoraria. Neufeld: Octapharma: Consultancy, Honoraria; Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Lambert: Educational Concepts in Medicine: Honoraria; Novartis: Honoraria; AstraZeneca: Research Funding.

Abstract: For the past decade, survival (S) for adults with ALL has remained at 30–40% despite achieving high complete remission (CR) rates of 70–90%. CALGB 19802 was designed to test the hypothesis that dose intensification of daunorubicin (D) and cytarabine (Ara-C) could improve disease-free survival (DFS) and that aggressive high dose intravenous (IV), oral (PO) and intrathecal (IT) methotrexate (MTX) could replace cranial irradiation (RT) for central nervous system (CNS) prophylaxis. Treatment consisted of 6 monthly courses of intensive therapy followed by 18 mos of maintenance. In pts & lt; 60 yrs, the D dose during induction and in post-remission therapy was increased in cohorts from 45 mg/m2 on days 1–3 (used in prior CALGB ALL studies) to 60 and then to 80 mg/m2/day X 3. In pts ≥ 60 yrs, D was increased from 30 to 60 mg/m2/day X 3. High-dose Ara-C and CNS prophylaxis with IV, PO, and IT MTX were given in post-remission modules for all pts with a goal of targeting serum methotrexate levels to be 1–2 μM at 30 hours following the IV MTX infusion. No cranial RT was given. From 1/99–1/01, 163 adults with untreated ALL were enrolled. Median age was 40 yrs (range, 16–82) and 33 (20%) were ≥ 60 yrs old; 61% were male. Of 127 centrally reviewed cases, 100 (79%) were precusor B-cell; 19 (15%) precursor T-cell; and 8 (7%) were bilineal or biphenotypic. A large proportion, 46 (46%) of 100 centrally reviewed and evaluable cases, had poor risk cytogenetics as defined in prior CALGB studies: 31 with t(9;22), 7 with t(4;11), 6 with −7 and 2 with +8. With a median follow-up of 4.4 years, the S and, especially DFS, for pts & lt; 60 yrs was improved for those who received D at 80 mg/m2 vs 60 mg/m2. The outcome of all 163 evaluable pts is summarized below: CR (%) 3 yr DFS [95% CI] 3 yr S [95% CI] OVERALL 128 (78.5) 32% [24–41] 36% [29–44]     AGE/ D DOSE      & lt; 60/ 60 mg/m2 36 (92%) 24% [11–39] 35% [20–50]      & lt;60/ 80 mg/m2 72 (79%) 43% [31–54] 46% [35–56]     60+/ 60 mg/m2 20 (61%) 10% [2–27] 8% [2–21] Disease progression during treatment occurred in 43 (26%) and 20 (12%) were removed for alternative therapies including 16 pts who received allo-SCT in CR1. Relapses have occurred in 84 (66%) pts; of these, 10 (8%) were isolated CNS relapses. CNS relapses tended to occur more frequently in pts with hour 30 serum MTX levels of & lt; 1μM during CNS prophylaxis. Age ≥ 60 was significantly associated with worse DFS and S. DFS was longer for precursor T-ALL (median S at 3 years not reached). Interestingly, neither WBC & gt; 30,000/μl nor adverse cytogenetics were significantly associated with worse outcomes. Higher levels of minimal residual disease (MRD) using quantitative clone specific PCR following induction therapy was predictive of inferior DFS (p = .02). In conclusion, omission of CNS irradiation did not result in higher CNS relapse rates than what has been reported in prior CALGB studies; furthermore, adjustment of MTX dosing to achieve targeted serum MTX levels may reduce the risk of CNS relapse. Younger pts who received 80 mg/m2 D had improved DFS and S. However, in contrast to other reports, the differences were not statistically significant. Thus, risk-adapted approaches to eradication of MRD using new agents and/or biologically targeted therapies should be incorporated into front-line treatment of ALL.

Abstract: We studied the prognostic significance of plasmablastic (PB) multiple myeloma (MM) in Eastern Cooperative Oncology Group Phase III trial E9486. Two reviewers independently reviewed 453 cases. They agreed on 37 PB (8.2%) cases and 416 non-PB cases, achieving an 85% concordance (P  〈  .0001). These PB cases had significantly lower hemoglobin and serum albumin levels, higher calcium and β 2-microglobuin levels, and higher percentage BM plasma cells (PC) by immunofluorescence. They had higher bone marrow PC labeling indices, higher serum soluble interleukin-6 receptor (sIL-6R) levels, and a higher probability of ras mutations. Three treatment regimens were used: vincristine, bis-chloro-ethyl nitrosourea (BCNU) melphalan, cyclophosphamide, and prednisone (VBMCP) alone; VBMCP with added cyclophosphamide (HiCy); or recombinant interferon α 2 (rIFNα2). Although the numbers are low, patients with PB had a significantly lower response rate versus non-PB MM when treated with VBMCP (treated, 47.1% v nontreated, 66.5% [P = .015]). Patients with nonresponding PB had a significantly higher progression rate than non-PB cases (30.6%v 11.8% [P  〈  .0001]), especially with VBMCP alone (35.3% v 15.8% [P = .002] ), and with added HiCy (37.5% v 9.8% [P  〈  .0001]), but not with added rIFNα2. Event-free and overall survival of PB MM was shorter (median years, 1.1 v 2.7 and 1.9 v 3.7, respectively [P  〈  .0001 for both]). In multivariate analysis, PB classification was also highly prognostic. There is no survival difference between the patients who were classified as PB by both reviewers versus patients classified as PB by only one reviewer. We conclude that PB MM is a discrete entity associated with more aggressive disease and shortened survival. Tumor cell rasmutations and increased sIL-6R may contribute to a higher proliferation rate and reduced survival. There were significant improvements in response and progression with the addition of HiCy and rIFNα2 to VBMCP, but the numbers were small and improved survival could not be shown.