Citations

e18549 Background: Many vitamin deficiencies can cause anemia. It is prudent prior to diagnosing a myeloid neoplasm, to check for vitamin deficiencies and correct them. Myelodysplastic syndromes with ring sideroblasts (MDS-RS) are associated with anemia. Pyridoxine (Vit B6) replacement may improve anemia found in sideroblastic anemia. The study was to determine how frequently Vit B6 was assessed, replaced and impact replacement had on outcomes in MDS-RS. Methods: Study subjects were from the Mayo Clinic Myelodysplastic syndrome (MDS) database which contains 1315 patients (pts). Appropriate IRB approval was obtained. Diagnosis of MDS and its sub-classification was done according to World Health Organization 2016 criteria. A response was any improvement in hemoglobin. Overall survival (OS) estimates were calculated using Kaplan-Meier curves and univariate and multivariate analysis was done using JMP software version 13. Results: Among 1315 pts with MDS, 161 pts had a diagnosis of MDS-RS. Median age was 73, and 55 (34%) pts were females. Thirty-nine (36%) pts had very low, 53 (50%) low, 9 (8%) intermediate, 3 (3%) high, and 2 (1%) had very high revised international prognostic score. The median white blood cell count was 5.4 x109, platelet count was 255 x109, and hemoglobin was 9.9 gm/dL. Five pts (3%) had a Vit B6 levels done; out of whom, 4 (80%) were not Vit B6 deficient. Among 42 (26%) pts who had Vit B6 replacement, 21 (50%) had no response, 4 (10%) had a response and 17 (40%) had unknown response. 103 (64%) of the pts were transfusion independent (TI). Overall survival in pts who are transfusion dependent was 68 months compared to 85 in pts who are TI (Wilcoxon P =.03). There was an improvement in OS in the group that had Vit B6 replacement compared to the group with no Vit B6 replacement (92 months vs 68 months, Wilcoxon P =.07). Response to Vit B6 replacement did not show OS benefit. Acute Leukemia transformation in Vit B6 replacement was 2% and 6% in pts. who did not have Vit B6 replacement (P= .4). Conclusions: Vit B6 was not checked often in MDS-RS pts. There was a borderline improvement in OS in Vit B6 replacement group (p= .07). Response did not affect OS. A larger prospective study is needed to study Vit B6 role in MDS-RS.

e19517 Background: Investigators cite complicated test (T) schedules as barriers to the conduct of clinical trials, especially T that do not contribute to outcome or pt safety. In MM protocols, some T are prone to being done inaccurately (e.g. UPEP, 24 hour urine collections), or are not useful (e.g. uric acid, AST/ALT) in determination of response (R) or safety. These T lead to increased cost, protocol violations, and do not enhance outcome. Methods: We analyzed data submitted for pts on E4A03 to examine frequency of missing data for R T: serum and urine (U) PEP, immunofixation (IFE) bone surveys (BS), and safety labs for C1-4. Results: Table outlines % pts with completed T. Most had T for serum M protein, as well as heme T but serum and U PEP, and IFE dropped off by C4. Other T e.g. uric acid were completed in 77%. Only 79% of pts had a BS repeated at C4. Incorrect or missing U data led to categorization of 16/445 (3.6%) pts as ineligible and was most frequent reason for ineligibility (69%). Missing U data led to 13/26 pts not evaluable. Analysis of SAE during the C1-4 revealed no SAE for hyperuricemia and < 5 SAE for AST/ALT. Only 5% of pts had lab-based SAE filed in 4 C. Conclusions: Required U T and BS to assess R in E4A03 were missing or completed inadequately and caused pts to be ineligible and or not evaluable. Such T need to be eliminated or replaced. Strategies to monitor data submission in real time may reduce subject loss due to T error. The requirement for routine T should be reassessed to create simpler trial design. Clinical trial information: NCT00098475. [Table: see text]

7621 Background: Thalidomide (Thal) in combination with dexamethasone (Dex) is an effective therapy for myeloma (MM). Though initially evaluated in MM because of its anti-angiogenic properties, it is not clear how much this contribute to its anti-MM effects. We examined whether the degree of angiogenesis influences response to Thal + Dex, as well as effect of therapy on marrow angiogenesis. We also examined whether expression of angiogenic cytokines by MM cells affect response to therapy. Methods: A total of 207 pts with newly diagnosed MM were randomized on the ECOG phase III trial (E1A00) to either Thal-Dex or Dex alone. Bone marrow microvessel density (MVD) was determined on 88 pts at diagnosis and at 4 mos after therapy in 25 pts. Expression of fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) by MM cells was determined by RTPCR on 60 pts at diagnosis and on 22 pts at 4 mos. In addition, the percentage of marrow PCs in apoptosis was determined at diagnosis and 4 mos in 43 pts. A decrease in the serum M protein by 50% or in its absence, a decrease in urine M protein by 50% was considered a response. Results: The median BM MVD at diagnosis was 33 (3–118), and was similar in the pts responding to therapy (36.4) and in the non responders (45.4). We also separately looked at those receiving the combination vs. Dex alone, and did not find any correlation. The expression of FGF and VEGF in the PCs did not predict response to therapy with either the combination or Dex. Among the 17 responding pts, MVD decreased by a mean of 12 compared to an increase in the mean MVD of 3 among the non responders (P = NS). There was no significant correlation between the level of FGF or VEGF expression and the marrow MVD. There was no correlation between the percentage of myeloma cells in apoptosis at baseline and response to therapy. Conclusion: While the anti-angiogenic activity of Thal may play a role in its anti-myeloma effect, baseline MVD or tumor cell expression of angiogenic cytokines do not predict resistance or response to Thal-Dex or Dex alone. The findings here confirm previous observations that marrow angiogenesis is not related to the degree of secretion of angiogenic cytokines by individual cells, but rather the cumulative effect of the tumor mass. No significant financial relationships to disclose.

17516 Background: The p53 tumor suppressor is commonly inactivated by mutations. Even in tumors without mutations, there are defects in the response to p53 activation. In MM, the prognostic significance of p53 mutation is unknown, while there has been no systematic study of p53 function. We seek to address these issues in this study. Methods: p53 mutation was studied by conformation sensitive gel electrophoresis with primers encompassing exons 1 to 10 followed by sequencing of DNA fragments with altered electrophoretic pattern in newly diagnosed MM patients entered into ECOG E9486 trial where patients were randomized to receive variations of melphalan-based conventional chemotherapy (VBMCP). Fisher’s exact tests were used to compare variables between patients. Kaplan-Meier survival curves were compared using the log-rank test. To investigate p53 function, we analyzed the expression of p53, and 3 of its transcriptional targets, APAF1, p21 and MDM2, in a separate cohort of 15 normal plasma cells (PC), 14 MGUS, 13 smoldering myeloma (SMM) and 101 MM (73 new and 28 relapsed) from the Mayo Clinic who had gene expression profiling performed on the Affymetrix U133A chip (Santa Clara, Ca). Results: Two hundred and sixty-eight patients had enough materials for study and were included in the analysis. The prevalence of p53 mutation was 3% (n = 9). Five of the 9 patients (56%, p = 0.001) with mutations also had p53 deletion (studied by fluorescent in-situ hybridization) resulting in bi-allelic loss of p53. Soft tissue plasmacytomas (37% v 7%, p = 0.018), and among the common translocations, t(4;14) and t(14;16) (50% v 18%) were more common in patients with p53 mutations. Despite similar response to treatment, those with p53 mutation had very short OS (16.7 v 41.4 months, p < 0.001). There was induction of p53 expression in MGUS and SMM with concurrent induction of APAF1, p21 and MDM2 whereas loss of this pattern was frequent in MM (45% in new MM and 60% in relapse MM compared to 15% in MGUS/SMM (p = 0.03)). Conclusions: p53 mutations are relatively rare in newly diagnosed MM patients but portend a short survival. However, functional abnormalities of p53 are prevalent and may be important in progression from MGUS/SMM to MM. [Table: see text]

8116 Background: POEMS syndrome, or osteosclerotic myeloma, is an uncommon plasma cell disorder associated with Peripheral neuropathy, Organomegaly, Endocrinopathy, M protein, and Skin changes, as well as bone lesions, Castlemans disease, and edema. The pathogenesis of POEMS is poorly understood, and its clinical course is distinct from Multiple Myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS). While various cytogenetic abnormalities have been well described in MM and MGUS, we provide the first report of testing for these abnormalities in POEMS syndrome. Methods: Using a prospectively held dysproteinemia database, we reviewed all cases of POEMS seen at our institution, identifying 36 with metaphase cytogenetic testing results, and 9 with fluorescence in situ hybridization (FISH) testing results. Combined cytoplasmic immunoglobulin/FISH testing (cIg- FISH) was performed with fluorescent-tagged antibodies to kappa/lambda immunoglobulin and FISH probes corresponding to the following anomalies: trisomies 3, 7, 9, 11, 15 and 17; del13/del13q; 14q32 split/del14; and t(11;14). Results: Five patients had insufficient plasma cells for cIg-FISH, and 9 were adequate for testing. Monosomy 13 was seen in 5 of the 9 cIg-FISH samples of which 2 of these cases also had apparent monosomy 14. cIg-FISH in one patient revealed trisomy 3 and 7. No abnormalities were seen at 11q13 (CCND1), 17p13 (p53) or translocations involving 14q32 (IGH). Thrity-eight total karyotypes analyses were attempted, though two showed an insufficient number of suitable metaphases. Of the 36 karyotype analyses, 31 were normal, 2 displayed characteristic plasma cell anomalies (hyperdiploid with structural anomalies), 2 treated patients displayed del20q anomalies and 1 patient had a constitutional 13;14 translocation. Conclusion: We are the first to report del13 as a possibly common abnormality in POEMS syndrome, detected by cIg-FISH in 5 of 9 (55%) samples with sufficient plasma cells, similar to the rate observed in MM and MGUS. The lack of abnormalities at 14q32 (IgH locus) is in contrast to MM and MGUS. Abnormal karyotypes, consistent with dividing plasma cells, are rare in POEMS, observed in only 2 of 36 (5.5%) cases. These observations could possibly lend insight into all three disorders. No significant financial relationships to disclose.

8108 Background: 2-methoxyestradiol (2ME2) is a natural endogenous product of estradiol metabolism with anti-angiogenic and anti-neoplastic properties that has demonstrated activity against multiple myeloma cell lines and xenografts in immunocompromised mice. We report results of the first phase II clinical trial of 2ME2 in pts with relapsed and plateau phase myeloma. Methods: This trial was designed with a one-stage design to accrue 60 pts in the setting of relapsed and plateau phase myeloma. 2ME2 was administered orally at a dose of 1000 mg daily. After the first 39 pts were accrued, based on the results of ongoing phase I trials, the dose of 2ME2 was increased to 800 mg twice daily for the remaining patients. Pts who were already on study at that point were also allowed to escalate their dose to 800 mg twice daily. The primary endpoint was overall response rate. Responses were assessed using Eastern Cooperative Oncology Group criteria. Results: Sixty patients were treated at Mayo Clinic and Dana Farber Cancer Institute. Median age was 60 years (range, 28–99). Thirty-one patients had relapsed/refractory myeloma and 29 patients had plateau phase myeloma. Median number of prior therapies was 4 including stem cell transplant (48%), thalidomide (62%), bortezomib (6%) and lenalidomide (3%). Therapy was well tolerated. Adverse events were anemia (35%), fatigue (35%), nausea (25%), diarrhea (20%), hot flashes (20%), headache (17%), muscle cramps (15%), and upper respiratory tract infection (15%). Most toxicities were mild (grade 1–2). Estimated progression-free survival rates for all pts at one, two, and three years are 24%, 16%, and 9% respectively. Three pts with plateau phase disease, have been on study for over 4 years without progression at 50, 60, and 63 months. Response assessment is ongoing; so far, whilst no partial responses have been seen, prolonged stable disease has been observed in 3 pts (5%). Conclusions: 2ME2 is a novel agent that appears to be safe and well tolerated. Although no responses have been seen, prolonged stable disease in some pts is promising. Preliminary pharmacokinetic data indicate that the dose of 2ME2 used in this study may be inadequate, and a new formulation with significantly better bioavailability will be tested soon in this patient population. No significant financial relationships to disclose.

8105 Background: IL-6 is the central myeloma growth factor and we have shown that abnormal production of IL-1beta in the myeloma microenvironment stimulates the generation of paracrine IL-6. A Phase II trial was completed using IL-1ra, which inhibits paracrine IL-6 production, and low dose Dexamethasone (Dex), which decreases IL-1 levels through myeloma cell apoptosis, in patients with smoldering/indolent MM (SMM/IMM). These patients are at the greatest risk for progression to active MM and most likely to benefit from anti- cytokine therapy. Methods: Patients that had ≥ 10% bone marrow plasma cells and/or an IgG or IgA M-spike ≥ 3 g/dL and did not require immediate chemotherapy were eligible. A total of 47 patients received 100 mg of IL-1ra SQ qd for 6 months unless clinical progression occurred. Responding patients were allowed to continue on therapy with IL-1ra alone. Low dose Dex (20 mg qweek) was added after 6 months of IL-1ra in non-responding patients. The primary endpoint was progression-free survival (PFS). Results: The 47 patients were at high risk for progression to active MM with 98% having ≥ 10% plasma cells, 89% generating IL-1 levels consistent with myeloma (≥ 1.0), and 32% having bone lesions. All 47 patients received IL-1ra initially and 25/47 subsequently received IL-1Ra/Dex. For the group of 47 patients, the median overall progression-free survival was 37.5 months. Three patients achieved a minor response (MR) to Anakinra alone; 5 pts achieved a PR and 4 patients an MR after addition of Dex. Seven patients had a decrease in the plasma cell labeling index (PCLI; a marker of myeloma cell growth) on Anakinra alone which paralleled a decrease in the high sensitivity CRP (a marker of serum IL-6 levels). The median PFS for patients without (n=12) and with (n=35) a ≥ 15% decrease in their baseline hsCRP was 6 months and > 3 yrs, respectively (p=0.002). Conclusions: In SMM/IMM patients at high risk for progression to active myeloma, treatment with IL-1 inhibitors (IL-1ra ± Dex) results in an increased PFS in patients that demonstrate a ≥15% reduction in the baseline CRP compared to those that do not respond. No significant financial relationships to disclose.

LBA8025 Background: We compared lenalidomide plus high (standard) dose Dex (R+HighD) versus lenalidomide plus low dose Dex (R+LowD) in newly diagnosed MM. Methods: Pts with untreated, symptomatic MM were eligible. Pts in both arms received lenalidomide 25 mg/day PO days 1–21 every 28 days. In addition, pts in the R+HighD arm received Dex 40 mg days 1–4, 9–12, and 17–20 PO every 28 days; pts in the R+LowD arm received Dex 40 mg days 1, 8, 15, and 22 PO every 28 days. The primary null hypothesis was that response rates at 4 months on the 2 arms are equivalent. Planned sample size was 196 eligible pts per arm with one-sided 0.10 Type I and 0.05 Type II error rate. Pre-planned interim analysis is performed by an independent DMC when full information is available on 25%, 50% and 75% of accrual. All analysis were intent to treat. Results: 445 pts (median age, 65 yrs) were accrued; 223 randomized to R+HighD, 222 to R+LowD. Arms were well balanced for age, gender, stage, bone lesions, hemoglobin, beta-2 microglobulin, performance status, bone marrow plasma cells, and M protein levels at baseline. Major grade 3 or higher toxicities included thromboembolism (22.1% with R+HighD vs 6.1% in R+LowD), infection/pneumonia (15.7% vs 7.5%) and hyperglycemia (9.7% vs 6.6%). Grade 3 or higher non-hematologic toxicities occurred in 65.9% (R+HighD) versus 54.9% (R+LowD) respectively; corresponding grade 4 or higher rates were 20.3% vs 13.1% respectively. Overall survival (OS) at first interim analysis was significantly superior with R+LowD, P<0.001; one year survival 96.5% (R+LowD) versus 86% (Rev+HighD). OS differences in favor of R+LowD were seen in pts <65 (P=0.015; one year rate 98% vs 90%) and pts 65 and older (P=0.004; one year rate 95% vs 83%), respectively. DMC recommended release of survival results, and recommended switching all pts to R+LowD. DMC also recommended closure of an expansion phase trial of R+HighD investigating optimal thromboprophylaxis. Conclusions: Lenalidomide plus low-dose dexamethasone is associated with superior OS compared to lenalidomide plus high-dose dexamethasone. This study has major implications for future use of high-dose dexamethasone in the treatment of MM. No significant financial relationships to disclose.

AimsRearrangement of the platelet‐derived growth factor receptor B (PDGFRB) gene defines a unique group of myeloid/lymphoid neoplasms with frequent eosinophilia and high sensitivity to tyrosine kinase inhibitors. This genetic abnormality is also rarely reported in Philadelphia‐like B‐cell acute lymphoblastic leukaemia/lymphoma (B‐ALL). PDGFRB rearrangement was initially thought to only occur in cases with 5q31–33 rearrangement as determined with conventional cytogenetics; however, there are reported cases with cryptic rearrangements. We aim to develop a broader strategy for screening of PDGFRB rearrangements of patients with myeloid/lymphoid neoplasms.Methods and resultsWe performed fluorescence in‐situ hybridisation (FISH) for PDGFRB rearrangement in 197 patients, including 70 with B‐ALL, 10 with myeloid neoplasms with 5q31–33 rearrangements, and 117 with eosinophilia (≥0.5 × 109/l in peripheral blood or ≥5% in bone marrow), and identified PDGFRB rearrangement in four of 197 (2.0%) cases. In an attempt to identify clinicopathological and genetic features that may have a stronger association with PDGFRB rearrangement, we analysed 13 patients with confirmed PDGFRB rearrangements, including 10 with myeloid neoplasms and three with B‐ALL. Among the 10 patients with myeloid neoplasms, eosinophilia was present in eight, monocytosis in two, 5q31–33 rearrangement in seven, and abnormal bone marrow morphology in all. All patients with myeloid neoplasms showed an excellent response to imatinib, including a patient in blast crisis. The three B‐ALL patients presented de novo, showed no eosinophilia, had a complex karyotype including 5q31–33 rearrangement, and had clinically aggressive courses with ultimate patient demise.ConclusionsThese findings suggest that a higher yield for the identification of PDGFRB rearrangement may result from an index of suspicion in patients with eosinophilia, monocytosis, bone marrow features of a myeloid neoplasm, and 5q31–33 rearrangement, and patients with Philadelphia‐like B‐ALL.