Immunotherapeutic approaches to treat patients with myeloid cancers show considerable promise. Delineation of the immunologic milieu in these patients is necessary to develop rationally-designed strategies. We have previously reported a phase I trial in which intermediate/high-risk(I/HR) MDS patients were vaccinated against NY-ESO-1 tumor antigen (anti-DEC-205-NY-ESO-1 fusion protein with poly-ICLC adjuvant; CDX-1401) in combination with decitabine (20 mg/m2/day x 5 days x 4 cycles). Vaccination of MDS patients induced NY-ESO-1-specific immune responses but there was significant intra-patient variability in the quantity and quality of these responses. CDX-1401 targets multiple populations of antigen presenting cells (APCs) including CD141Hi conventional dendritic cells (cDCs). Compared to other APCs, CD141Hi cDCs express higher levels of DEC-205, an antigen uptake receptor, and TLR3, the poly-ICLC receptor. These cells regulate anti-tumor immune responses in solid tumor models and are necessary for the efficacy of checkpoint inhibitors. Thus, we hypothesized that the observed variations in immune response to vaccine resulted from quantitative and/or qualitative differences in CD141Hi cDCs in MDS. Overall, in MDS patients compared with healthy donors, there was a 9-fold decrease in the frequency of CD141Hi cDCs (0.001 ± 0.002% versus 0.009 ± 0.006% respectively; p < 0.001). In contrast with this finding, frequencies of the related CD1c+ cDC population were not different (0.18 ± 0.11% versus 0.27 ± 0.61% respectively; p = 0.12). Strikingly, MDS patients with the highest frequency of CD141Hi cDCs demonstrated a greater functional response to vaccination (both humoral and T-cell mediated). Expression of DEC-205 in cDCs from MDS patients was not lower than in those from healthy donors, suggesting that response to vaccination was not mediated by differential expression of the vaccine target. To further analyze gene expression in cDCs, we performed RNA-seq analysis of DCs isolated from healthy donors (n = 3) and a vaccine responsive MDS patient from the study. Principal component analysis showed that gene expression profiles were similar in CD141Hi and CD1c+ cDCs from MDS and normal patients, and further these profiles were distinct from plasmacytoid DCs and CD34+ progenitors. This suggests that for MDS patients with detectable CD141Hi populations, cDC function is intact. We expanded our observations to a larger cohort of untreated HR MDS patients and confirmed a selective decrease in the baseline number of bone marrow CD141Hi cDCs (n = 17; 0.002% ± 0.006%) compared to healthy donors (n = 5; 0.14 ± 0.01%; p < 0.001). We further characterized cDC progenitors in a subset of these patients using flow cytometry (n = 8). MDS patients demonstrated a population of bipotent cDC progenitors (early pre-DC) with an expected ratio of differentiation to committed CD1c+ cDC progenitors and terminally differentiated CD1c+ cDCs (p < 0.01). In contrast, the expected relationships between early pre-DCs and CD141Hi cDC committed progenitors or terminally differentiated CD141Hi cDCs was lost (p= 0.33 and 0.79 respectively). These data suggest a defect in the differentiation program for CD141Hi cDCs in MDS patients. We then hypothesized that decitabine treatment might promote a more normal cDC differentiation pattern. Using an in vitro model of cDC differentiation, we found that decitabine treatment increased differentiation of MDS CD34+ progenitors to CD1c+ cDCs by an average of 1.72 ± 0.96 fold (n = 3). However, we were unable to detect a similar effect on CD141Hi cDC differentiation. Since in vitro models do not reliably recapitulate the human environment, we analyzed serial bone marrow samples isolated from patients treated on study with decitabine and vaccination (n = 4). In these assays, 2/4 and 3/4 patients showed increased numbers of both CD141Hi and CD1c+ cDC at the end of study compared to pre-treatment. Together, these data suggest that CD141Hi cDCs are selectively reduced in patients with HR MDS and that decitabine treatment promotes cDC differentiation in vitro and in MDS patients. Optimal immunotherapeutic approaches for MDS patients may therefore benefit from strategies that address defects in APC differentiation and function.

7037 Background: Hypomethylating agents (HMA) are increasingly being utilized for upfront therapy of acute myeloid leukemia (AML) in older adults. These individuals often have multiple comorbidities and/or lower performance status predicting for poor outcome following intensive induction chemotherapy. We asked whether these same clinical factors influenced the outcomes of HMA induction therapy in older adults. Methods: We reviewed 138 consecutive patients aged ≥ 60 years who received upfront HMA with either decitabine (20 mg/m2 for 5-10 days) or azacitidine (75 mg/m2 for 7 days) for newly diagnosed AML at our institute. ECOG PS, comorbidities, Charlson Comorbidity index (CCI), Hematopoietic Cell Transplant – Comorbidity Index (HCT-CI), and overall survival (OS) were assessed. Results: Median age was 75 (range 60-93) years. Two-thirds (95) were male. Median white blood cell count was 4.5 x 109/L (0-121). Median marrow blasts were 45% (10-98%). Half of patients (50%) had secondary AML. 87 (63%) had adverse cytogenetics, 13 (9%) had FLT-3 mutant and 14 (10%) had NPM-1 mutant AML. ECOG PS was assessed as 0 (20 pts, 14%), 1 (85 pts, 62%), 2 (29 pts, 21%) and 3 (4 pts, 3%). Comorbidities were measured as 0 (24 pts, 17%), 1 (51 pts, 37%), 2 (32 pts, 23%) or ≥ 3 (31 pts, 23%). CCI was 2-3 (20 pts, 14%), 4-5 (63 pts, 46%), 6-7 (42 pts, 31%), and ≥ 8 (13 pts, 9%). HCT-CI was 0-1 (40 pts, 29%), 2-5 (78 pts, 56%) and 6-12 (20 pts, 15%). The majority (115, 83%) of patients received decitabine induction. Twelve patients (9%) underwent stem cell transplant. Median OS of all patients was 7.47 months. Factors significantly associated with poorer outcome by log-rank analysis were: age ≥ 75 (p = 0.0001), marrow blasts < 50% vs ≥ 50% (p = 0.002), ECOG PS 2-3 (p = 0.04), CCI ≥ 6 (p = 0.0006), HCT-CI 0-1 vs 2-5 (p = 0.0129), HCT-CI 2-5 vs 6-12 (p = 0.0066). Choice of HMA, number of comorbidities, and de novo vs secondary AML did not predict outcomes. Conclusions: Advanced age ≥ 75 yrs, marrow blasts ≥ 50%, ECOG PS 2-3, and high comorbidity indices, as determined by CCI and HCT-CI, were associated with shorter overall survival following induction HMA in older AML patients. Future prospective studies to validate these findings are needed.

Relapsed/refractory (r/r) Acute Myeloid Leukemia (AML) remains a therapeutic challenge. Cytarabine arabinoside (AraC) forms the backbone of most regimens, with complete responses (CR) ranging from 17 to 20%. Lenalidomide (Len) is approved by the FDA for multiple myeloma and myelodysplasia and has demonstrated activity in AML. We developed a phase I study to evaluate the safety and tolerability of Len in combination with intermediate dose AraC (1.5 g/m2/day given on days 1–5) in adults with r/r AML. The maximally tolerated dose for this combination was 10 mg daily on days 6–26 of a 28 day cycle. Dose de-escalation from 25 mg was required due to rash, liver function abnormalities, and hypokalemia. Of 32 evaluable patients, five achieved CR (16%), 5CRi (16%) and 3 had hematological improvements for an overall response rate of 41% (13/32). Median overall survival (95% confidence interval) for patients treated on study was 5.8 (2.5–10.6) months and disease free survival was 3.4 (2.3–6.2) months. This single institute phase I trial of Len and intermediate dose AraC was associated with marked skin and other toxicities. At the dose and schedule tested, this combination did not appear to result in improved CR over single agent AraC for r/r AML.

Introduction: Relapsed/refractory (r/r) and secondary acute myeloid leukemia (AML) are associated with poor outcomes and low survival rates, particularly in older individuals. Because there is no standard salvage regimen, the choice of therapy for patients (pts) is often based on institutional experience. The Polish Adult Leukemia group reported high anti-leukemic activity and acceptable toxicity with CLAG±M in r/r AML pts (Wierzbowska et al, Eur J Haematol 2008); however these patients were primarily younger individuals with a median age of 45 years. Jaglal et al (Leuk Res 2014) reported their single institute experience showing that CLAG-M was superior to historical 7+3 for induction of secondary AML pts after prior azanucleoside therapy. Based on these data, we have been utilizing CLAG±M as a standard induction/re-induction strategy for r/r and secondary AML pts at our institute since 2013.

Over 11,000 people in the US are diagnosed with acute myeloid leukemia (AML) each year, and despite attempts to improve therapy, the overall 5-year survival remains 26%, largely due to a high rate of relapse. Defining the mechanisms responsible for persistence of the malignant clone is essential to improve outcome in AML. Activation of WNT signaling pathways through nuclear localization of β-catenin has been linked to development and progression of AML.2,3 It is well known that nuclear translocation of β-catenin in this manner induces target gene transcription through physical interaction with members of the TCF/LEF family of transcription factors. While there are conflicting data on the role of WNT signaling in normal hematopoietic stem cell self-renewal, mouse models have demonstrated that β-catenin is critical for AML stem cell self-renewal.2–4 These data, combined with the clinical observation that increased canonical WNT signaling in AML blasts at diagnosis is associated with decreased rates of relapse-free and overall survival, suggested a potential clinical benefit for WNT suppression.5,6 While this approach has shown promise in the treatment of AML, questions remain as to which subtypes of AML will benefit.7,8 In this study, we characterize activation of the canonical Wnt pathway in a cohort of patients with AML and found that while a majority of patients at diagnosis showed predominantly nuclear β-catenin, treatment of primary samples with a next generation WNT inhibitor had variable effects on blast survival and phenotype. Together, these data highlight the inherent challenges in targeting the WNT pathway in AML and emphasize that this strategy will require identification of subtypes of AML, or even individual patients, that will most benefit from this approach. To identify such patients, we utilized multispectral imaging flow cytometry technology to quantify nuclear localization of β-catenin, the biochemical hallmark of WNT pathway activation. Using this technique, we determined nuclear β-catenin in AML blasts obtained at diagnosis from a cohort of 21 patients exhibiting normal karyotype (Table 1). We selected this population since 50% of patients exhibit a normal karyotype, representing the largest group of patients with AML.1 Ficoll-separated, unfractionated bone marrow mononuclear cells were obtained from patients with AML through the tissue repository at Roswell Park Cancer Institute (RPCI) under an IRB-approved protocol. To prepare the patient samples for analysis, they were first incubated with LIVE/DEAD Far Red stain according to the manufacturer’s instructions (Invitrogen). Cells were stained with mouse anti-human CD45 (phycoerythrin (PE)-conjugated, clone HI30) and CD34 (allophycocyanin (APC) conjugated, clone 4H11, (eBioscience, San Diego, CA, USA) followed by fixation with 2% methanol-free paraformaldehyde (Polysciences, Inc., Warrington, PA, USA). Cells were permeabilized with 0.1% Triton-X and stained with 0.5 mg monoclonal mouse anti-β-catenin antibody (AlexaFluor 488-conjugated, clone L54E2, Cell Signaling Technology, Danvers, MA, USA) in 0.1% Triton-X for 30 min on ice. Prior to analysis on an ImageStream X (Amnis Corporation, Seattle, WA, USA), DAPI (Life Technologies, Grand Island, NY, USA) was added to the cells. Table 1. Clinical characteristics of samples from patients with normal karyotype AML. For all samples, single cells were identified for analysis based on focus and the blast gate was defined based on the CD45Dim/side scatterLow (SSCLow) immunophenotype. Among our patients, we observed blasts that exhibited predominantly cytoplasmic or nuclear β-catenin (Figure 1A). To quantify cellular distribution of β-catenin, we used the IDEAS v.6.0 software package (Amnis). Nuclear β-catenin was quantified through calculation of a similarity score, a log-transformed Pearson correlation coefficient between the pixel values of β-catenin and DAPI images.9 A higher score indicates increased nuclear localization of β-catenin. Overall, we observed that 14 of 21 samples exhibited a median similarity score over 0, indicating that in these diagnostic samples the median cellular localization of β-catenin was biased towards the nucleus (Figure 1B). Figure 1. Analysis of nuclear β-catenin in primary AML samples. (A) Representative images obtained using an ImageStream imaging flow cytometer; primary AML samples from Patient 18 (top) and 8 (bottom). Images shown are brightfield, β-catenin (green), ... Since previous studies have demonstrated a correlative association between nuclear β-catenin levels at the time of original diagnosis and increased risk of relapse,5 we also quantified β-catenin localization in 7 paired samples obtained at diagnosis and at relapse (Figure 1C). In this selected cohort, we observed a significant increase in the β-catenin similarity score in relapsed samples compared to their paired diagnostic sample. With the caveat that this cohort is limited in terms of numbers, localization of β-catenin to the nucleus appeared to be greater in AML blasts at relapse compared to blasts at diagnosis. Among the documented consequences of β-catenin activation in myeloid leukemia are decreased apoptosis and differentiation and increased proliferation.10,11 To test whether inhibiting WNT signaling affected survival or differentiation of primary AML blasts with different levels of nuclear β-catenin, we used a compound (iCRT3) that inhibits WNT signaling by blocking the interaction between β-catenin and TCF family transcription factors.12 We tested the effects on 3 different samples; a diagnostic sample from Patient 18 (relatively high levels of nuclear β-catenin); a diagnostic sample from Patient 8 (predominantly cytoplasmic localization of β-catenin); and the relapse sample from Patient 4 (termed 4R), which exhibited increased nuclear β-catenin compared to its diagnostic sample. AML samples were co-cultured with irradiated HS-27 feeder cells supplemented with human hematopoietic growth factors, as previously described.13 For all 3 samples, treatment with iCRT3 resulted in a significant decrease in the expansion of viable cells compared to control (P<0.05) (Figure 2A). We then analyzed the immunophenotype of surviving blast cells (CD45DimSSCLow) using standard multispectral flow cytometry. Treatment of blasts from Patient 18 with iCRT3 significantly increased the percentage of blasts expressing the mature CD14 and CD11b markers compared to vehicle control (P<0.05) (Figure 2B). Interestingly, treatment of this sample with iCRT3 also increased the percentage of CD34+, CD38+ blasts compared to control (P<0.05) (Figure 2C). Thus, while inhibition of WNT signaling may increase differentiation of some blasts, there may be other populations that are resistant to or even stimulated by blockade of the pathway. In contrast, neither the diagnostic sample with low levels of nuclear β-catenin or the relapse sample with high β-catenin exhibited any changes in blast immunophenotype after culturing with iCRT3 compared to vehicle. Figure 2. Pharmacological inhibition of WNT signaling in primary AML samples. (A) Average fold expansion of cell number of AML samples (n=4 biological replicates for each sample) following six days of treatment with vehicle control (light gray bar) versus 25 mM ... In total, these observations that β-catenin has variable effects on AML blast immunophenotype and number support those of Gandillet et al.7 While base-line nuclear β-catenin levels in primary AML blasts may not correlate with response to pharmacological inhibition of this pathway, samples with low base-line levels still responded to therapy, as shown by significantly decreased cell numbers. This suggests this approach may be more widely applicable than previously thought. Further separation of patients with normal karyotype AML based on mutation status or even age may refine the definition of the ideal target population. Sample availability precluded testing paired samples from diagnosis versus relapse to determine the relative efficacy of inhibiting β-catenin. However, a critical experiment will be to compare the relative sensitivity to β-catenin inhibition between paired samples obtained at diagnosis versus relapse. In addition, it is possible that these data are specific to the iCRT3 inhibitor, which targets the interaction between β-catenin and TCF/LEF proteins. Other WNT signaling inhibitors, such as XAV939 and C59, which target the pathway at alternative points (by enhancing degradation of β-catenin or reducing WNT ligand activity respectively) could produce different effects.14,15 In summary, our studies using a next generation pharmacological agent to target WNT signaling in primary AML show the clinical potential of targeting this pathway while confirming previous studies demonstrating that blockade of WNT signaling will likely have variable results. Thus, these findings highlight the fact that additional work is necessary to identify those clinical subsets of AML patients most susceptible to anti-WNT therapy.

Cancer testis antigens (CTAs) are promising cancer associated antigens in solid tumors, but in acute myeloid leukemia, dense promoter methylation silences their expression. Leukemia cell lines exposed to HMAs induce expression of CTAs. We hypothesized that AML patients treated with standard of care decitabine (20mg/m2 per day for 10 days) would demonstrate induced expression of CTAs. Peripheral blood blasts serially isolated from AML patients treated with decitabine were evaluated for CTA gene expression and demethylation. Induction of NY-ESO-1 and MAGEA3/A6, were observed following decitabine. Re-expression of NY-ESO-1 and MAGEA3/A6 was associated with both promoter specific and global (LINE-1) hypomethylation. NY-ESO-1 and MAGEA3/A6 mRNA levels were increased irrespective of clinical response, suggesting that these antigens might be applicable even in patients who are not responsive to HMA therapy. Circulating blasts harvested after decitabine demonstrate induced NY-ESO-1 expression sufficient to activate NY-ESO-1 specific CD8+ T-cells. Induction of CTA expression sufficient for recognition by T-cells occurs in AML patients receiving decitabine. Vaccination against NY-ESO-1 in this patient population is feasible.

7058 Background: Outcomes of standard induction chemotherapy in older patients (pts) ≥ 60 years old with acute myeloid leukemia (AML) are significantly affected by medical co-morbidities and performance status. We asked whether these same factors impact the outcome of upfront hypomethylating therapy. Methods: We retrospectively reviewed 83 consecutive pts ≥ 60 yrs old with newly diagnosed AML who underwent induction therapy with hypomethylating agents at our institute between 2008-13. Sixty-nine patients received decitabine (20 mg/m2 daily for 5-10 days) and 14 received azacitidine (75 mg/m2 daily for 7 days). Number of underlying co-morbidities, Charlson Co-morbidity Index (CCI), Hematopoietic Cell Transplant- Comorbidity Index (HCT-CI), Eastern Cooperative Oncology Group (ECOG) performance status (PS), and overall survival (OS) were assessed. Results: Median age was 75.5 (range 60-92) years. Three-quarters (63) were male. Median white blood cell count was 5 x 109/L (range 0-121). Over half (46, 55%) the pts had secondary AML, and 31 (40%) had adverse cytogenetics. Six pts (7%) had FLT-3 mutant and 8 (10%) had NPM-1 mutant AML. ECOG PS was assessed as 0 (13 pts, 16%), 1 (55 pts, 66%), 2 (12 pts, 14%), and ≥ 3 (3 pts, 4%). Co-morbidities were measured as 0 (19 pts, 23%), 1 (28 pts, 34%), 2 (19 pts, 23%) or ≥ 3 (17 pts, 20%). CCI was 2-3 (6 pts), 4-5 (39 pts), 6-7 (28 pts), and ≥ 8 (10 pts). Sixteen pts (20%) achieved a complete response with an overall response date of 28%. Median OS of all pts was 9.1 (95% CI 4.5-12.4) months. ECOG was significantly associated with OS (p = 0.039) with median durations of 12.6 (PS 0), 11.3 (PS 1), 3.5 (PS 2) and 0.5 (PS ≥ 3), months, respectively. Co-morbidities, CCI, or HCT-CI were not significantly associated with survival (p = NS). Conclusions: Our results suggest that PS, not co-morbidities, predicts outcomes in older AML pts receiving upfront decitabine/ azacitidine. These data contrast with prior studies showing that co-morbidities, CI, HCT-CI, and PS all significantly impact outcomes of intensive induction. Prospective studies of the potential benefit of hypomethylating therapy in older AML patients with multiple co-morbidities are warranted.

Abnormal activation of WNT signaling is a significant driver of leukemogenesis, implicating this pathway as a potential therapeutic target. However, inhibition of this pathway is not uniformly effective in primary AML blasts, suggesting that identification of specific patients who will benefit from this therapy will be critical. In this study, we obtained samples from AML patients with normal karyotype at diagnosis and measured WNT signaling using imaging flow cytometry (n=21). This technique was used to quantify nuclear localization of β-catenin, the biochemical hallmark of active WNT signaling, in primary blast cells based on the CD45Dim/SSCLow immunophenotype. In agreement with earlier studies, the majority (14/21) of AML patients demonstrated increased nuclear β-catenin in blast cells.

Older patients with acute myeloid leukemia (AML) have poor outcomes with standard induction chemotherapy. We retrospectively reviewed our institute's experience with epigenetic (Epi) versus cytarabine‐ and anthracycline‐based intensive chemotherapy (IC) as induction in newly diagnosed AML patients aged 60 years and older. One hundred sixty‐seven patients ( n = 84, IC; n = 83, Epi) were assessed; 69 patients received decitabine and 14 azacitidine. Baseline characteristics between the IC and Epi patient cohorts were not statistically different except for age, initial white blood cell count, and comorbidity index. Overall response rate (ORR, 50% vs. 28%, respectively, P < 0.01) and complete response rate (CRR, 43% vs. 20%, respectively, P < 0.01) were superior following IC vs. Epi. Although univariate analysis demonstrated longer overall survival after IC (10.7 vs. 9.1 months, P = 0.012), multivariate analysis showed no independent impact of induction treatment. Treatment‐related mortality was not statistically different in the two groups. Outcomes of patients with secondary, poor cytogenetic risk, FLT‐3 mutated AML, or relapsed/refractory disease after IC or Epi were not significantly different. Outcomes of patients receiving IC versus a 10‐day decitabine regimen ( n = 63) also were not significantly different. Our results suggest that IC and Epi therapy are clinically equivalent approaches for upfront treatment of older patients with AML and that other factors (feasibility, toxicity, cost, etc.) should drive treatment decisions. Prospective randomized trials to determine the optimal induction approach for specific patient subsets are needed. Am. J. Hematol. 90:639–646, 2015. © 2015 Wiley Periodicals, Inc.

Mutations in IDH1 and IDH2 occur in 15-20% of AML cases, resulting in the production of 2-hydroxyglutarate, which promotes aberrant hypermethylation of DNA in leukemic cells. Although these mutations have been shown to have prognostic implications for patients with AML, optimal treatment strategies have yet to be defined. We retrospectively identified forty-two patients with AML treated with DNA methyltransferase inhibitors (DNMTIs) decitabine (n = 36) or azacitidine (n = 6) and performed analysis of stored samples for the presence of IDH1 and IDH2 mutations. Of the forty-two samples analyzed, seven (16.7%) had IDH mutations. Thirteen patients (31%) achieved remission [(complete remission (CR)/complete remission with incomplete count recovery (CRi)/partial response (PR)] after treatment with a DNMTI, five of seven (71.4%) with IDH mutations and eight of thirty-five (22.9%) without IDH mutations (P = 0.01). When adjusted for age at diagnosis, sex, bone marrow blast percentage and cytogenetic, the odds of achieving response after administration of a DNMTI among patients with an IDH mutation was 14.2 when compared to patients without an IDH mutation (95%CI: 1.3-150.4). IDH1 and IDH2 mutations may predict a favorable response to DNMTI in patients with AML.

BACKGROUND:Acute myeloid leukemia (AML) characterized by Feline McDonough Sarcoma-like tyrosine kinase-3 (FLT-3) internal tandem duplication (ITD) mutations have poor outcomes. Treatment options are limited, because these mutations confer resistance to conventional chemotherapy. FLT-3 inhibitors such as sorafenib have been studied as a single agent and in combination with conventional chemotherapy or azacytidine with fair responses.PATIENTS AND METHODS:Here we describe our preclinical and clinical experience with the combination of the DNA hypomethylating agent, decitabine and sorafenib for the treatment of FLT-3 ITD-mutant AML.RESULTS:In vitro treatment of the human FLT-3 ITD-mutant AML cell line, MV4-11, with both drugs significantly improved growth inhibition over single-agent therapy and resulted in synergistic antitumor effects (combination index < 1). A case series of 6 patients treated with off protocol combination of decitabine and sorafenib demonstrated overall responses in 5 patients (83%) with a median survival of 155 days. Four of the 5 patients (80%) with relapsed/refractory AML achieved complete responses with incomplete count recovery. The combination was also well tolerated.CONCLUSION:Further investigation is warranted to confirm these responses.

Introduction: Patients with acute myeloid leukemia (AML) characterized by FMS-like tyrosine kinase-3 (FLT-3) internal tandem duplication (ITD) mutations have poor outcomes, especially in the relapsed setting. Although small molecule inhibitors of FLT-3 have been explored for these patients, many inhibitors have demonstrated limited single-agent efficacy with short response durations. Sorafenib, a multi-kinase inhibitor with activity against FLT-3, has previously been evaluated alone and in combination with induction chemotherapy or azacytidine in AML patients. Here we describe our experience with the combination of the DNA hypomethylating agent, decitabine (D), and sorafenib (S) for the treatment of FLT-3 ITD mutant AML.

e18014 Background: Hematological malignancies (HM) are treated by chemotherapy, radiotherapy or combination of both. The risk of developing a second malignancy after Hodgkin disease (HD) treatment ...

We designed a phase II study evaluating the upfront combination of clofarabine and daunorubicin in acute myeloid leukemia (AML) patients≥60 years old. The median age of the 21 patients was 69 (range 60–85) years. Fourteen patients (67%) had unfavorable risk features. The principal toxicities were grade ≥3 infections and prolonged myelosuppression. Three (14%) deaths occurred from infectious complications. Six (28.6%) patients achieved complete remission including three (21.4%) of 14 patients with unfavorable AML. The median disease-free survival was 6.8 months and the median overall survival was 11.2 months.

BACKGROUNDSeveral studies have suggested that low 25(OH) vitamin D3 levels may be prognostic in some malignancies, but no studies have evaluated their impact on treatment outcome in patients with acute myeloid leukemia (AML).METHODSVitamin D levels were evaluated in 97 consecutive, newly diagnosed, intensively treated patients with AML. MicroRNA expression profiles and single nucleotide polymorphisms (SNPs) in the 25(OH) vitamin D3 pathway genes were evaluated and correlated with 25(OH) vitamin D3 levels and treatment outcome.RESULTSThirty‐four patients (35%) had normal 25(OH) vitamin D3 levels (32‐100 ng/mL), 34 patients (35%) had insufficient levels (20‐31.9 ng/mL), and 29 patients (30%) had deficient levels (<20 ng/mL). Insufficient/deficient 25(OH) vitamin D3 levels were associated with worse relapse‐free survival (RFS) compared with normal vitamin D3 levels. In multivariate analyses, deficient 25(OH) vitamin D3, smoking, European Leukemia Network genetic group, and white blood cell count retained their statistical significance for RFS. Several microRNAs and SNPs were associated with 25(OH) vitamin D3 levels, although none remained significant after multiple test corrections; one 25(OH) vitamin D3 receptor SNP, rs10783219, was associated with a lower complete remission rate (P = .0442) and with shorter RFS (P = .0058) and overall survival (P = .0011).CONCLUSIONSIt remains to be determined what role microRNA and SNP profiles play in contributing to low 25(OH) vitamin D3 level and/or outcome and whether supplementation will improve outcomes for patients with AML. Cancer 2014;120:521–529. © 2013 American Cancer Society.

e18018 Background: AD occurring in the setting of MDS is challenging to recognize and incorporate into the treatment plan. We assessed the clinical presentations, laboratory abnormalities and outcome of patients with MDS and AD. Methods: Records of MDS patients treated at Roswell Park Cancer Institute between 2007 and 2010 were reviewed (n=123). Results: AD was identified in 10 MDS patients (8.1%): 70% were males, median age was 60.6 years (41-75). AD manifested as seronegative polyarthritis in 2, bronchiolitis obliterans in 2, Hashimoto’s thyroiditis in 2, and 1 (10%) for each of rheumatoid arthritis, systemic lupus, polymyalgia rheumatica, Sjogren syndrome and relapsing polychondritis. Laboratory autoimmune markers were: anti nuclear antibodies in 2, rheumatoid factor in 2, anti-double stranded DNA in 1 and anti phospholipid syndrome with thrombosis in 1. Corticosteroids were the most common used treatment for AD (60%). Regarding the MDS diagnosis; 50% had refractory anemia with excess of blasts-1 and -2, 20% refractory anemia with ring sideroblasts, 10% for each of chronic myelomonocytic leukemia, refractory anemia and MDS/myeloproliferative neoplasm. Normal cytogenetics were noted in 70% of patients, 20% with complex karyotype and 10% had monosomy 7. Hypomethylating agents were used to treat MDS in 80% of patients and in one case were associated with concomitant improvement of AD. Overall survival from diagnosis with MDS was 54 months (6-127). Conclusions: Our experience with one patient and review of the literature suggest that both AD and MDS could benefit from treatment with hypomethylating agents. This warrants a prospective clinical trial.

Abstract Background: Association of non-secretagogues, metformin and thiazolidindiones, with lower cancer risk and improved survival has led to numerous clinical studies exploring their benefit as adjuvants in cancer chemotherapy. However, the most utilized, metformin, is contraindicated in patients undergoing radiologic studies involving intravenous administration of iodinated contrast media, such as patients with acute myeloid leukemia (AML). In these patients, metformin should be either withheld until renal function returns to normal or substituted with an alternate, in practice, often injectable insulin. Little is known about the consequences of metformin's substitution in patients whose cancer care requires periodic exposures to contrast dye or in which its reinitiation appears unsafe. Objective: This study compares the utilization of insulin and non-secretagogues, metformin and thiazolidindiones, in patients with diabetes mellitus newly diagnosed with AML or solid tumors. Methods: All diabetes mellitus (DM) patients diagnosed with AML (n1=65), breast (n2=290), ovarian (n3=46), prostate (n4=105) and kidney cancer (n5=95) between January 2003 and December 2010 at Roswell Park Cancer Institute in Buffalo, NY were included in the study (n=601). Patient demographics, tumor pathology, outcomes, baseline co-morbidities and self-reported drug therapy were documented. Follow-up began at cancer diagnosis and ended with first confirmed recurrence and/or death. Cases lost to follow-up were censored at the date of last contact. Kaplan-Meyer with log-rank statistics and Cox proportional hazards models were used for all multivariate analyses. A nominal significance level of 0.05 was used in all testing. Results: The median age was 62 years old in the solid tumor group and 69.5 years old in the AML group. Baseline utilization of non-secretagogues in DM patients diagnosed with solid tumors was associated with significantly improved overall mortality, as compared to baseline insulin utilization (X2=4.071, P=0.044). No baseline glucose lowering drug class utilization advantage was observed in the AML group. A stratified analysis of solid tumors and AML groups according to the respective drug utilization revealed a statistically significant difference in mortality in the favor of non-secretagogue utilization in DM patients with solid tumors, but not with AML (X2=258.36, p<0.001). Conclusion: We confirm a survival benefit for the patients receiving non-secretagogues as compared to insulin in the solid tumors group. The absence of non-secretagogue protection in the AML group could be potentially attributed to the substitution of metformin with injectable insulin at the time of AML diagnosis. Citation Format: Zachary A. P. Wintrob, Huan-Ching Chuang, Dustyn S. Miller, Jonathan L. Rabey, Thang Q. Bui, Michelle E. Amsler, Laurie-Ann Ford, Meir Wetzler, Alice C. Ceacareanu. Missing the benefit of metformin in AML: A problem of contrast. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-17. doi:10.1158/1538-7445.AM2013-LB-17

Abstract Background Epigenetic therapy (Epi) with the hypomethylating agents, azacitidine (Aza) and decitabine (Dec), is increasingly being utilized for induction treatment of older AML patients (pts) based on studies demonstrating both tolerability and prolonged survival. By contrast, standard “7+3” intensive chemotherapy (IC) effectively induces remission in many individuals but is associated with significant toxicity and higher mortality. We compared our institute's experience with Epi vs. IC for the upfront treatment of newly diagnosed AML pts ≥60 years old. Methods We performed a retrospective chart review of 164 pts ≥ 60 yrs old with newly diagnosed AML who underwent initial therapy at our center between 3/2008-2/2013. Half (n=84; 51%) received IC with regimens containing cytarabine 100 mg/m2 IV for 7 days and daunorubicin 60 mg/m2 IV for 3 days. Half were treated with Epi (n=82; 49%) regimens containing either Dec (20 mg/m2 IV daily for 5 or 10 days) or Aza (75 mg/m2 sq daily for 7 days). Kaplan Meier method, log rank test, and univariate cox proportional hazard models were used to assess overall survival (OS) and correlation with covariates of interest. Results Baseline pt characteristics demonstrated a difference in the median age of pts in each group (IC 67 vs. Epi 75 yrs; p <0.01). All other factors were comparable: ECOG status 0-2 (96% vs. 96%, p=1.0), WBC (12.0 x 109/dL vs. 4.5 x 109/dL; p=0.08), hemoglobin (9.2g/dL vs. 9.4g/dL; p=0.39), platelets (69 x 109/dL vs. 54 x109/dL; p=0.99), marrow blasts (53% vs. 45%; p=0.10), peripheral blasts (21% vs. 9%; p=0.14), poor-risk cytogenetics (56% vs. 66%; p=0.21). At our center, older AML pts receiving IC had superior complete response at any time point (CRatp)(43% vs. 21%; p< 0.01) and higher overall response rates (ORR=CR+CRp) (50% vs. 28%; p<0.01) versus Epi-treated pts. IC also resulted in a longer median OS as compared to Epi (10.6 vs. 7.9 mos; p=0.01). Thirty-day mortality and leukemia-free survival (LFS) were similar across the two groups (IC 10% vs. Epi 11%; p=0.8; 11.2 vs. 9.3 mos; p=0.47 respectively). Interestingly, in pts with AML characterized by poor-risk cytogenetics (n=77; 46%), the choice of induction (IC vs. Epi) did not impact outcome and yielded similar CRatp (39% vs. 27%; p= 0.4) and OS (10.3 vs. 7.8 months; p=0.4). Choice of Epi drug (Aza vs. Dec) did not impact results. Thirty-three percent of pts (n=55; IC 38% vs. Epi 28%) had refractory or relapsed disease (RR-AML) after induction, requiring ≥1 salvage treatment. We found that selection of either IC or Epi as prior treatment had no effect on CR or ORR in RR-AML pts receiving salvage. In multivariate Cox regression analysis, older age, higher ECOG score, increased peripheral blasts, and poor-risk cytogenetics were independently associated with inferior survival. By comparison, marrow blast percentage, hemoglobin, and choice of induction therapy did not impact OS (IC vs. Epi: HR 0.79; CI 0.508-1.237, p= 0.31). Conclusions Our results suggest that IC and Epi represent clinically equivalent approaches for the upfront treatment of older AML pts. In spite of significantly higher CR and ORR in the IC group, our finding of improved OS following IC vs. Epi was not substantiated in multivariate analysis, suggesting that this difference may be explained by the comparatively younger age of pts in the IC group. Leukemia-free survival and 30-day mortality were the same for IC vs. Epi-treated pts, as were all response and survival outcomes in the poor-risk cytogenetics subgroup. These data highlight the growing need for prospective clinical trials to conclusively determine the respective roles of IC vs. Epi therapy in older AML pts. Disclosures: No relevant conflicts of interest to declare.