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Introduction: Myelodysplastic syndromes (MDS) are a heterogenous group of blood disorders defined by peripheral cytopenia(s), bone marrow failure, morphological dysplasia, and risk of progression. To understand the genetic, epigenetic and biological factors associated with the initiation and progression of MDS, NHLBI created the National MDS Study (NCT02775383). This is a prospective cohort study conducted at 92 community hospitals and 29 academic centers enrolling patients undergoing diagnostic work up for suspected MDS or MDS/myeloproliferative neoplasm (MPN) overlap syndrome. Eligible patients have yet to receive any therapy directed at their cytopenias. Previously untreated cytopenic participants underwent centralized histopathology and data review at the time of enrollment for assignment into distinct subcategories: MDS, MDS/MPN overlap, AML, and Other. Targeted exon sequencing of 96 genes was performed using marrow specimens from the first 300 consecutive individuals in the study. Here we report the genetic mutations for this cohort. Methods: NovaSeq 6000 was used for deep sequencing at a mean coverage of 1,286X and mean breadth (bases covered at ≥100X) of 99.8%. Reads were aligned against build GRCh38 using BWA-MEM, and VarScan2 was used to detect SNVs and INDELS. Variants were filtered for those with an allele base quality of >25 in combination with rule-based and manual review criteria. Subjects in the Other category without an identified malignancy were considered clonal cytopenias of undetermined significance (CCUS) when a mutation or a clonal cytogenetic change was present. Fisher's exact and Wilcoxon rank sum tests in combination with Bonferroni correction were applied to compare groups. Results : A total of 350 putative nonsynonymous pathogenic variants in 36 genes with an allele frequency of >.05 were identified across 150 patients (50%). At least one variant was noted in the following proportion of individuals: 61/72 (85%) with MDS, 13/13 (100%) with MDS/MPN, 15/17 (88%) with AML, and 61/198 (31%) in the Other category, of which 48 were CCUS and 13 were other cancers. Two CCUS patients only had a cytogenetic abnormality. Table 1 shows the distribution of variants in each subcategory of patients for the most commonly mutated genes in our cohort of 300 subjects. Mutations in these genes were enriched in specific groups: SF3B1, STAG2,TP53, and ASXL1 in MDS; TET2 in MDS/MPN; and IDH2 and TP53 in AML (one-sided p<0.0012). None were enriched in the Other group. Within the CCUS subset, 21 genes were mutated, with 37 of 50 (74%) patients having a mutation in TET2, ASXL1, SRSF2, SF3B1, or DNMT3A. The heatmap presented in Figure 1 summarizes variants by subject and allele frequency. Pair-wise comparisons of baseline characteristics of subjects between MDS, MDS/MPN, AML, or CCUS groups revealed no significant differences for age or sex. The CCUS group had significantly higher hemoglobins than the MDS group with median hemoglobin levels of 11.35 and 9.40 g/dL, respectively (p<0.0084). AML had significantly lower platelets compared to all other groups (median of 53 vs. > 110x109/L , respectively, p<0.0084). All groups significantly differed in their median ANC with AML having the lowest (0.8x109/L), followed by MDS (1.5x109/L), CCUS (2.45x109/L), and MDS/MPN overlap (5.95x109/L) (p<0.0084). There was no difference in the median number of variants per patient between groups or correlation with age (rs=0.11, p=0.18). The maximum variant allele frequency (maxVAF) per patient was highest in the MDS/MPN group (median = 0.42, range = 0.38-0.91) and lowest in the CCUS group (median = 0.37, range =0.06-0.98) with the MDS/MPN group having a significantly higher maxVAF compared to the MDS and the CCUS groups (p<0.0084). The proportions of subjects with mutations was similar for those who had abnormal (92% [34/37]) and normal (91% [80/88]) cytogenetics. Conclusions: Incorporation of gene-panel sequencing in the comprehensive evaluation of 300 adult cytopenic patients identified half of the cohort with potentially pathogenic variants. Ultimately, a diagnosis of CCUS was possible in 48 of 183 subjects (26%) not diagnosed with MDS, MDS/MPN overlap syndrome, AML, other cancers or clonal cytogenetics. This study continues to serially bank samples from patients with CCUS, in addition to MDS, MDS/MPN, and ICUS, with the goal to better understand the natural history of these diseases and their progression. Disclosures Lindsley: Jazz Pharmaceuticals: Research Funding; Takeda Pharmaceuticals: Consultancy; Medlmmune: Research Funding. Bejar:Celgene: Consultancy; Takeda Pharmaceuticals: Research Funding; AbbVie/Genentech: Consultancy, Honoraria; Astex/Otsuka: Consultancy; Modus Outcomes: Consultancy; Daiichi-Sankyo: Consultancy. Al Baghdadi:Celgene: Consultancy, Honoraria; Heron: Consultancy, Honoraria; Tracon: Equity Ownership; Epizyme: Equity Ownership; Bristol Myer Squibb: Consultancy, Honoraria; Sunesis: Equity Ownership; Portola: Equity Ownership; Heron therapeutics: Equity Ownership; Cardinal health: Consultancy, Honoraria; Bristol Myer Squibb: Equity Ownership; Celgene: Equity Ownership; Spectrum pharmaceutical: Equity Ownership; Astrazeneca: Equity Ownership; Seattle genetics: Equity Ownership; Roche: Consultancy, Honoraria. DeZern:Astex Pharmaceuticals, Inc.: Consultancy; Celgene: Consultancy. Foran:Agios: Honoraria, Research Funding. Gore:Celgene Corporation: Consultancy, Research Funding. Komrokji:DSI: Consultancy; Agios: Consultancy; Novartis: Speakers Bureau; JAZZ: Speakers Bureau; pfizer: Consultancy; celgene: Consultancy; Incyte: Consultancy; JAZZ: Consultancy. Maciejewski:Alexion: Consultancy; Novartis: Consultancy. Starczynowski:Kurome Therapeutics: Consultancy. Sekeres:Millenium: Membership on an entity's Board of Directors or advisory committees; Syros: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees.

CMML is a lethal myeloid neoplasm with no therapies that improve its dismal prognosis. Inhibition of BET family members has been proposed as a therapeutic strategy based on preclinical data identifying BRD4 as a therapeutic target in acute myeloid leukemia. However, despite potent on-target transcriptional remodeling, early phase clinical trials have demonstrated only modest activity secondary to a variety of resistance mechanisms. In ovarian cancer BET inhibitor (BETi) treated cells, compensatory upregulation and addiction to pro-survival kinase networks have been observed. Given that over 50% of CMML cases have mutations upregulating kinase signaling, we hypothesized that BETi resistance is mediated by these networks in CMML and can be targeted therapeutically. We tested this hypothesis by performing a limited screen of kinase inhibitors alone and in combination with the IC20 of the BETi INCB54329 in 8 human leukemia cell lines. This screen revealed that the IC50 of the PIM inhibitor (PIMi) INCB53914 decreased after co-treatment with BETi in a majority of the leukemia cell lines tested. Synergy was validated chemically in U937, TF1 and SKM1 leukemia cells using other selective inhibitors of BET and PIM. We next assessed the activity of the BET-PIM combination in 14-day colony formation assays with 10 unique CMML bone marrow mononuclear cell (BM-MNCs) patient samples(Fig. 1A). These studies revealed that combination therapy significantly suppressed clonogenicity versus BMNCs treated with vehicle or single drug alone. Finally, this synergy was validated in vivo in 36 patient derived xenografts (PDX) from 3 CMML patients, as manifest by reduced leukemic burden/engraftment in CMML PDX treated with combination therapy(Fig. 1B). To explore the mechanism by which BETi and PIMi therapeutically synergize we treated U937 and SKM1 leukemia cells with INCB54329 and measured mRNA and protein levels for all PIM isoforms. Surprisingly, we identified that PIM1 was increased following treatment with INCB54329, other BETi, or a JQ1-derived PROTAC (Fig. 1C). PIM1 upregulation was also manifest in INCB54329 persistor U937 leukemia cells generated by daily BETi treatment for 6 weeks. Testing across a broader panel of leukemia cell lines revealed an inverse correlation between PIM1 induction and decrease in the IC50 of PIMi following BETi treatment, suggesting PIM1 upregulation confers sensitivity to combination therapy. Consistent with this, isogenic SKM1 leukemia cells engineered to overexpress PIM1 were resistant to INCB54329 and were more sensitive to INCB53914 versus controls cells. Recent studies have demonstrated that inhibitory miRNAs, especially those located near super-enhancers, are suppressed by BET inhibition. Given that several miRNAs are known to control PIM1 expression, we hypothesized that paradoxical PIM1 upregulation following BETi treatment was due to down-regulation of select miRNAs. To test this, we treated our leukemia cell models with broad inhibitors of miRNA activity (i.e., AGO and Dicer inhibitors) and observed a dose dependent increase in PIM1 levels similar to that seen with BET inhibition(Fig. 1Di). Further, integrating public H3K27 CHIP-seq and miRNA super enhancer datasets and using computational prediction algorithms, we identified 6 candidate miRNAs that could regulate PIM1 and were predicted to be controlled by BET inhibitors. Of these, only miR-33a levels were reduced in a dose dependent manner in SKM1 cells by BETi treatment(Fig. 1Dii). This was confirmed by genetically silencing all BET proteins, which suppressed miR-33a levels in SKM1 leukemia cells. Finally, miR-33a mimics (but not control miRNAs) abolished BETi-induced upregulation of PIM1(Fig. 1Diii). Collectively, these studies established BET and PIM inhibition as a novel and potent combination therapy for CMML that is mediated by miR-33a-dependent upregulation of PIM1(Fig. 1E). Disclosures Liu: Incyte Corporation: Employment. Patnaik:Stem Line Pharmaceuticals.: Membership on an entity's Board of Directors or advisory committees. Lancet:Daiichi Sankyo: Consultancy, Other: fees for non-CME/CE services ; Agios, Biopath, Biosight, Boehringer Inglheim, Celator, Celgene, Janssen, Jazz Pharmaceuticals, Karyopharm, Novartis: Consultancy; Pfizer: Consultancy, Research Funding. Komrokji:Novartis: Speakers Bureau; JAZZ: Speakers Bureau; JAZZ: Consultancy; Agios: Consultancy; Incyte: Consultancy; DSI: Consultancy; pfizer: Consultancy; celgene: Consultancy. Epling-Burnette:Incyte Corporation: Research Funding. List:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Haura:Incyte Corporation: Research Funding. Reuther:Incyte Corporation: Research Funding. Koblish:Incyte Corporation: Employment.

Abstract MDS with chromosome 5q deletion [del(5q)] is uniquely sensitive to clonal suppression by lenalidomide (LEN), yielding high rates of cytogenetic and erythroid response. Although haploinsufficiency for a candidate tumor suppressor gene within the common deleted segment (CDS) has been implicated in the pathogenesis of del(5q) MDS, no specific gene products account for the karyotype-dependent LEN sensitivity. Using primary AML cells, we showed that LEN is selectively cytotoxic to del(5q) cells, inducing cell cycle arrest at the G2 > G1 junctures and apoptosis in a concentration-dependent fashion. Now we show that the CDS-encoded Cdc25C and PP2A phosphatases (PPTs) serve as molecular targets for LEN. Cdc25C and PP2A are dual specificity PPTs that regulate cell cycle. The genes encoding the catalytic subunit alpha (PP2ACa), the dominant catalytic isoform, and the regulatory subunit B (beta isoform PR 52) of the PP2A holoenzyme reside within the del(5q) CDS. Real-time RT-PCR showed that Cdc25C and PP2ACa gene expression is significantly reduced in primary del(5q) AML and MDS BM-MNC compared to non-del5q and normal controls. A Cdc25C FISH probe confirmed presence of only a single allele in del(5q) specimens [n=5] vs. normal karyotype [n=5] with no overlap with the EGR1 locus. We found that LEN inhibited rHu-Cdc25C activity with IC90 inhibitory concentrations ≤10nM. Similarly, PP2A PPT activity was inhibited by LEN in enzyme immunoprecipitates from Ramos cells at sub-micromolar concentrations. In U937 cells, we confirmed intracellular Cdc25C and PP2A inhibition, showing concentration-dependent retention of the inhibitory p-Tyr15 -Cdc2 substrates for Cdc25C with corresponding phosphorylation of the PP2A substrate Ser216 Cdc25C, findings reproduced by treatment with the PP2A selective antagonist, fostreicin. Cdc25C immunoprecipitation showed that phosphorylation of Ser216 Cdc25C increased binding to the 14-3-3 protein with consequent cytoplasmic sequestration confirmed by fluorescence microscopy. Phosphorylation of histone H2A.X Ser139 was unchanged after LEN treatment, indicating that phosphorylation of the inhibitory Cdc25C serine does not arise from upstream DNA damage activated kinases. Importantly, siRNA suppression of Cdc25C gene expression in U937 cells promoted LEN-specific apoptosis in 45% of cells, which increased to 68% after fostreicin inhibition of PP2A. These data indicate that haplodeficiency for the Cdc25C and PP2ACa genes promotes selective sensitivity of del(5q) cells to LEN-induced apoptosis. Haplodeficiency of critical drug-able targets may represent a novel strategy for tumor selective therapy.

Abstract Abstract 1640 Background: The introduction of radioimmunotherapy (RIT) into clinical practice for the treatment of follicular lymphoma (FL) occurred at a time at which many patients did not have prior exposure to rituximab. Clinical trials in the relapsed/refractory setting, as well as consolidation in the upfront setting have included a small number of patients that had been previously treated with rituximab or a rituximab containing treatment regimen. We evaluated the effect of prior rituximab therapy on the efficacy of RIT. METHODS: The prospective lymphoma database was queried for all patients having received a single dose of yttrium-90 ibritumomab tiuxetan for relapsed/refractory FL which had previously been treated with systemic therapy (patients receiving only prior external beam radiation therapy were excluded). The database includes all consecutive adult patients diagnosed with lymphoma seen at Mayo Clinic Rochester. The diagnosis of follicular lymphoma was as by WHO classification and centrally reviewed. Patients with evidence of histologic transformation to diffuse large B cell lymphoma prior to RIT were excluded. Time to treatment failure (TTF) was defined as the time from RIT to next anti-lymphoma therapy. RESULTS: 111 patients were identified. 57 (51%) were male. Median age at time of RIT was 58 (19–88). Median time from diagnosis to RIT was 35 (6–281) months in patients having received prior treatment with rituximab and 47 (12–272) months in those who had not (p=0.19). 63 (57%) of patients received prior treatment with rituximab or rituximab containing chemotherapy. Median number of prior therapies was 2 (1–10), which was not different between the rituximab treated or untreated groups [2(1–6) vs 2(1–10) p=0.12]. Median TTF was 10.0 months in the patients having received prior rituximab and 10.1 months in those that had not (p=0.29). Figure 1. The median overall survival from RIT was not reached, but appeared similar (Kaplan-Meier estimate 125 months without prior rituximab exposure vs 95 months with prior rituximab exposure; p=0.33). CONCLUSIONS: Prior rituximab exposure does not seem to adversely impact the time to treatment failure or overall survival in those patients treated with RIT. While the data leading to the approval of RIT were accrued prior to the routine clinical use of rituximab, our data demonstrate similar clinical benefit of RIT in patients with prior exposure to rituximab or rituximab containing therapy. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 1572 Background: The incidence of histologic transformation (HT) of follicular lymphoma (FL) to an aggressive lymphoma has been reported to range from 10–75%. The British Columbia Cancer Agency reported a risk of 3% per year (Al-Tourah AJ, et al J Clin Oncol 2008;26: 5165–5169). The hallmark of HT is the acquisition of new somatic mutations and genomic instability within the malignant clone. DNA damaging agents such as radioimmunotherapy (RIT) may increase the risk of HT by inducing additional DNA damage. The incidence of HT after RIT is unknown. This single institution study analyzes the risk of histologic transformation (HT) in patients with FL after RIT treatment with yttrium-90 ibritumomab tiuxetan. METHODS: The Mayo Clinic Lymphoma Data Base were queried for all patients having received a single dose of yttrium-90 ibritumomab tiuxetan for FL. The Mayo Clinic Lymphoma Database includes all consecutive adult patients diagnosed with lymphoma evaluated at Mayo Clinic Rochester. The prospective radioimmunotherapy lymphoma database was also utilized (GAW). The diagnosis of FL was defined by current WHO Classification, and all cases were centrally reviewed. HT was defined as the development of histologically proven diffuse large B cell lymphoma in patients with history of Grade 1 or 2 FL (change to Grade 3A/B FL was not included). Patients having demonstrated evidence of HT prior to RIT were excluded from this analysis. RESULTS: 119 consecutive patients were included. 64(54%) were male. The median follow-up was 57(range 2–175) months. RIT was administered as treatment for progressive FL in 96.6% of patients. RIT was administered as a consolidation therapy in 4(3.4%) patients. The median number of prior systemic treatments was 2 (range 0–10). The median time from diagnosis to RIT was not different in patients with HT vs. those without HT 44 (10–186) vs. 40 months (range 1–394) (p=0.30), respectively. The median time to HT from RIT was 13 months (range 1–97). Four patients had HT within 3 months of RIT. The median survival after HT was 15 months (range 1–147). The estimated five year risk of transformation from RIT by Kaplan-Meier in patients with fludarabine exposure and those without exposure was 55% and 29% (p=0.0498). 10 year risk from the time of RIT was 64% with fludarabine exposure and 31% without (p=0.0498). The relative risk of HT after RIT in patients previously treated with fludarabine was HR=4.1 (95% CI: 2.0–7.9). The median number of prior therapies in patients with HT vs. patients without HT was 2 (0–6) and 1 (0–10) (P=0.33). CONCLUSIONS: To our knowledge, our data is the first to estimate the risk of HT after the use of RIT. The estimated overall risk of HT of 31% at 10 years from diagnosis in patients without fludarabine exposure is similar to that of patients in whom RIT has not been administered. The estimated overall risk of HT of 64% in those patients having received purine analogues appears to be increased. We conclude that RIT appears to not increase the risk of HT in patients who did not receive prior purine analogue therapy. The differences in extent and mechanisms involved in DNA damage induced by radiation vs. purine analogues may play a role in clinical differences in observed rates of HT. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 2059 Introduction: Two randomized trials have demonstrated a benefit in progression free survival (PFS) of 18–20 mofor maintenance treatment with lenalidomide after auto-PBSCT for multiple myeloma (MM). Although results on survival benefit are conflicting and quality of life (QOL) data is lacking, some have begun to recommend maintenance. No study has evaluated patient perceptions of maintenance. We conducted a systematic survey of MM patients (pts) regarding what constitutes a meaningful benefit that would make burdens of maintenance (toxicity and cost) acceptable. Methods: We mailed a brief self-administered survey in 3 waves to 1159 consecutive living pts evaluated at Mayo Clinic. The survey provided background on the standard of care for MM in transplant eligible pts and data on maintenance. Pts were asked to estimate the magnitude of OS benefit that would be acceptable for varying degrees of toxicity and cost. Results: Of the 1159 surveys sent, 886 pts (83.2%) responded, including 150 notifying us of a decision not to participate. 736 pts returned a completed survey (66% raw response rate). (56%) male, 407 (55%) had undergone auto-PBSCT, 467 (63%) had discussed maintenance with a physician, and 9 (1%) pts had received no treatment. 10% of pts had MM for 3–12 mo, 14% for 1–2 yr, 13% for 2–3 yr, 20% for 3–5 yr, 44% for 5 yr or more. Pt age: 4% 18–49 yr, 24% 50–59 yr, 40% 60–69 yr, 27% 70–79 yr, and 6% >80 yrs. The most worrisome potential toxicity was identified as peripheral neuropathy by 27% of pts, cytopenias by 24%, LE DVT 20%, fatigue 15%, nausea 8%, diarrhea/constipation 7%. In response to a question about whether they would choose maintenance if there was a PFS benefit but no improvement in OS, 92% would opt for maintenance if it were known to cause mild toxicity, while 77% would opt for maintenance despite moderate toxicity. Subsequent questions included cost and toxicity considerations and required pts to identify minimum acceptable duration of OS benefit to estimate more precisely a meaningful clinical benefit. If treatment was free, had no toxicity, and the OS benefit was 1 yr or less, 49% would choose maintenance (see Figure). In the same scenario, if toxicities were mild, the proportion of pts who choose maintenance was similar (46%). If pts experienced moderate toxicity, 42% choose maintenance. With rising financial burden (out-of-pocket) and toxicity, the proportion of pts who choose maintenance declined (see Table). For example, if the cost was $25/mo, mild toxicity experienced, and the OS benefit was one year or less, 46% would choose maintenance, while 39% of pts would choose maintenance if it cost $250/month and there was moderate toxicity. If maintenance cost $10,000/mo and was associated with mild or moderate toxicity, 18% and 17% of pts would choose treatment, respectively. Conclusions: For the first time, we have described the broad range of patient perspectives regarding trade-offs in the treatment of MM with maintenance therapy. We found that willingness to be treated with maintenance declined when actual benefits were provided in concrete numeric terms compared with a general statement of PFS benefit. The discrepancy between the 92% of pts choosing to undergo maintenance if free and mild toxicity when there is a PFS benefit but no OS benefit, compared to 49% of pts choosing maintenance if free, mild toxicity, and associated with an OS benefit of 1 yror less; suggests pts have difficulty understanding the concept of PFS. We also found that the magnitude of benefit required to consider maintenance was affected by cost and toxicity. In our experience, pts typically incur a cost of approximately $25/mo and experience mild toxicity. In this study, nearly half (46%) of such pts would opt for maintenance if the OS benefit was 1 year or less while only 33% of pts would opt for maintenance if the OS benefit was 6 months or less. Our data implies that good care in MM requires detailed conversations about each and every patient's priorities and expectations prior to making recommendations for or against such treatments. Disclosures: No relevant conflicts of interest to declare.

SummaryHistological transformation (HT) of follicular lymphoma (FL) to an aggressive lymphoma after chemotherapy remains a key issue. The incidence of HT after radioimmunotherapy (RIT) is unknown. This single institution study analysed the risk of HT in FL after treatment with yttrium‐90 ibritumomab tiuxetan in 115 consecutive patients treated during 1987–2012. RIT was administered for progressive FL in 111 (97%) patients and as first‐line therapy in the remaining 4. 28% (n = 32) had HT, occurring at a median of 60 months from diagnosis and 20 months after RIT. 48% (12/25) of patients who received fludarabine developed HT. The estimated 10‐year risk of HT in the fludarabine and non‐fludarabine groups was 67% and 26% respectively (P = 0·015). Only prior fludarabine was significantly associated with predicting the risk of HT after RIT. 8% (9/115) of patients developed therapy‐related myelodysplastic syndrome/acute myeloid leukaemia (tMDS/AML) at a median of 41·4 months (range, 5–89). The estimated 10‐year risk of tMDS/AML in non‐fludarabine treated patients (n = 90) versus fludarabine treated (n = 25) was 13% and 29%, respectively. The estimated overall risk of FL undergoing HT at 10 years without fludarabine exposure appears similar to patients reported in the literature that have not received RIT. Patients with prior purine‐analogue therapy are at significantly higher risk of HT.

Patients with diffuse large B‐cell lymphoma (DLBCL) and pre‐treatment bone marrow (BM) involvement require a restaging BM biopsy to document complete remission (CR). We investigated whether BM assessment by restaging PET‐CT could obviate the need for a repeat BM biopsy. Patients with DLBCL and a positive BM biopsy at diagnosis were identified from the Mayo Clinic Lymphoma Data Base. The concordance of BM status on restaging histopathology and PET‐CT reports and the positive (PPV) and negative predictive value (NPV) of PET‐CT were determined. One thousand eighty patients with DLBCL were evaluated and 69 patients (6%) had DLBCL involving the BM at diagnosis. Of 46 patients who completed frontline chemoimmunotherapy, 34 had a restaging PET‐CT and BM biopsy and were included in the analysis. Thirty‐three patients had a negative BM by both PET‐CT and BM biopsy; one patient had persistent BM involvement by biopsy and PET‐CT. Thus, restaging PET‐CT had 100% PPV and 100% NPV for assessing residual BM disease. The findings were validated in a prospective cohort of 68 DLBCL patients treated on a phase II clinical trial where four patients (6%) had DLBCL involving the BM at diagnosis. All had a negative BM by both restaging BM biopsy and PET‐CT. Compared with the gold standard of BM biopsy, PET‐CT had a 100% NPV to exclude residual BM disease after frontline therapy. If further validated, DLBCL practice guidelines and response criteria could be modified so that BM biopsy is no longer required to document CR if the restaging PET‐CT is negative. Am. J. Hematol. 89:865–867, 2014. © 2014 Wiley Periodicals, Inc.