Refractory Cytopenia With Unilineage Dysplasia Research Articles

Danazol As First-Line Therapy for Myelodysplastic Syndromes

▪Introduction: Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematological disorders characterized by ineffective hematopoiesis and variable degrees of peripheral cytopenias. Neither curative nor standard therapy has been available yet for the majority of patients with MDS. Patients with available matched donor may undergo an allogeneic bone marrow transplant with a potential cure rate 30-50%. Danazol is a synthetic anabolic steroid with properties similar to corticosteroids, such as inhibition of interleukin-1 and TNF-α production. Also, has demonstrated activity in immune cytopenias and aplastic anemia but its efficacy in MDS has shown contradictory results. Recently there has been increasing interest in telomere dysfunction in hematological diseases. Short telomeres are the major prognostic risk factor for clonal evolution to myelodysplasia and acute leukemia. Danazol not only prevents telomere loss, but a mean increase occurs with improvement observed early during the course of hormone therapy. In our center with poor access to new strategies and therapies the use of danazol remains as an attractive option for patients with MDS because of its low cost. In this study we aim to document the clinical evolution of patients diagnosed with MDS treated with danazol as first-line therapy in our institution.Methods: We include patients diagnosed with MDS according to WHO criteria treated with danazol between 2005 and 2015. Response was defined as one or more of the following criteria: a rise in the platelet count >25 x 109/I, an increase in hemoglobin >2 g/dl or disappearance of a previous requirement for red blood cell transfusion, or an increase in neutrophil count >0.5 x 109/L. All patients received packed red blood cell and platelet transfusions according to physician criteria. Patients were given intravenous or oral antibiotics as needed as prophylaxis. Criteria for stop danazol included: no response to treatment, toxicity or patient’s refusal to continue treatment. Blood counts were preformed at least 1-month intervals for the first 4 months. We compared those who responded versus no responders using the Student’s t test or Mann-Whitney U test as corresponded.Results: Forty-two patients with MDS were treated with danazol. Median follow-up was 12 months (range 3-75). Median dose used was 400 mg (range 100-600) orally in two divided doses. Mean duration of treatment for all patients was 6 months (range 3-72 months). The distribution by WHO subtypes included 26 refractory cytopenia with multilineage dysplasia (RCMD) (62%), 6 patients with refractory cytopenia with unilineage dysplasia (RCUD), 6 refractory anemia with excess blasts (RAEB), 2 refractory anemia with ring sideroblasts (RARS) and 1 MDS associated with isolated del(5q). Twenty-four (60%) patients presented clinical response. Response for patients with anemia was 23.8% (10/24), increase in absolute neutrophil count occurred in 36.8% (7/19), and 60% (24/40) presented an increase in platelet count. Time to initial response was 2 months (range, 1-8) while time to better response of 3 month (range, 1-8). Response was not associated to any MDS classification or administrated dose. Toxicity was mild and danazol was not discontinued in any patient. Side effects included three patients with gastrointestinal symptoms, and 4 patients reported weight gain. Median overall survival was 24 months (CI95% 5.1-42). Fifteen patients died (35.7%). Five patients progressed to AML.Conclusion: Different agents have been used in MDS. However, for the majority of patients with MDS no curative treatment exists. In conclusion our data suggest that Danazol may be effective in MDS with minimal toxicity, especially in patients with thrombocytopenia. Response was independent of severity, WHO classification and administrated dose. [Display omitted] DisclosuresGomez-Almaguer:Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees.

107 MONITORING OF THERAPEUTIC RESPONSE TO LENALIDOMIDE IN DEL(5Q) MDS USING A RAPID 5-PARAMETER FLOW CYTOMETRIC DEL(5Q)-SCORE

We characterized the prevalence of hematopoietic and lymphoid disease for 2923 consecutive patients presenting at 29 hospitals from August 2003 to June 2007. Diagnoses were made in our laboratory using WHO criteria based on morphologic, immunophenotypic, cytogenetic, FISH and molecular data. A total of 611 subjects (322 males/289 females) were prospectively diagnosed with MDS using WHO (2001) criteria. Update and re-evaluation of cases using MDS (2008) criteria resulted in 649 MDS cases. Using WHO (2008) criteria, refractory cytopenia with multilineage dysplasia (RCMD) accounted for 68% of total cases, refractory anemia with excess blasts (RAEB), 16.3%; refractory anemia (RA), 6.5%; refractory cytopenia with unilineage dysplasia (RCUD), 4%; and MDS-unclassifiable (MDS-U), 4.5%. Subjects were administered questionnaires and information on previous disease, work histories and exposures to potential etiologic agents such as benzene (BZ) was obtained. A total of 80/649 (13.2%) were determined to have some BZ exposure. The frequency of clonal cytogenetic abnormalities in all MDS was 30%, the most common being +8 > del(20)q > del(7q) > del(5q), while the analogous frequency in BZ-exposed cases was only 24%. To further investigate the characteristics of MDS associated with BZ, we identified a subset of cases with high BZ exposure. These BZ signal cases were each matched by age and gender to two cases with no known BZ exposure. When contrasting BZ signal cases vs matched cases with no BZ exposure, we found a high odds ratio (OR) for the WHO subtype MDS-U (OR = 11.1), followed by RAEB and RCUD (OR = 1), RA (OR = 0.7) and RCMD (OR = 0.6). Multilineage dysplasia with abnormal eosinophils (MDS-Eo) was strongly associated with BZ exposure, whereas the relative risk of clonal cytogenetic abnormalities was reduced for high BZ-exposed cases (OR = 0.5). These findings are strongly indicative that MDS subtypes are influenced by BZ exposure, and taken together with previous studies, the features of MDS-Eo suggest that altered immune regulation plays a major role in the pathogenesis of MDS following chronic exposure to BZ.

Analysis of the karyotype abnormalities and its prognostic in 298 patients with myelodysplastic syndrome

目的探讨骨髓增生异常综合征（MDS）患者的细胞遗传学特点及其与MDS诊断分型、疾病进展和预后的关系。方法回顾性分析2008年6月至2013年10月浙江大学医学院附属第一医院收治的298例MDS患者的临床特征及预后情况，随访观察并进行相关性研究。结果难治性血细胞减少伴单系发育异常（RCUD）18例，难治性贫血伴环状铁粒幼红细胞（RARS）8例，难治性血细胞减少伴多系发育异常（RCMD）104例，难治性贫血伴原始细胞过多（RAEB）-1 76例，RAEB-2 85例，MDS不能分类5例，单纯del（5q）2例。染色体异常检出率39.6%，单纯数目异常45例，单纯结构异常31例，42例两种异常同时存在，均为不平衡易位及复杂异常。RAEB组（RAEB-1+RAEB-2）染色体异常检出率及复杂染色体异常检出率均高于非RAEB组（RARS+RCMD+RCUD）（47.2%对29.2%，P=0.002）。根据IPSS-R积分系统分组，除极低危组外，随着危险分层的递增，染色体异常检出率逐渐增加（P<0.05），且随着IPSS-R积分越高，转化为白血病的概率越高（P<0.01）。+8染色体异常占所有核型异常的19.5%，在RAEB组+8染色体异常组2年总生存率低于正常染色体组（43%对68%，P=0.005）。结论染色体核型分析是MDS患者判断预后的一个独立因素，对于MDS的诊断、治疗方案的制定及预后判断均有较大意义，+8染色体异常作为中等预后的染色体异常，在RAEB组预后差于正常染色体核型。

Refractory thrombocytopenia and neutropenia: a diagnostic challenge.

The 2008 WHO classification identified refractory cytopenia with unilineage dysplasia (RCUD) as a composite entity encompassing refractory anemia, refractory thrombocytopenia (RT), and refractory neutropenia (RN), characterized by 10% or more dysplastic cells in the bone marrow respective lineage. The diagnosis of RT and RN is complicated by several factors. Diagnosing RT first requires exclusion of familial thrombocytopenia, chronic auto-immune thrombocytopenia, concomitant medications, viral infections, or hypersplenism. Diagnosis of RN should also be made after ruling out differential diagnoses such as ethnic or familial neutropenia, as well as acquired, drug-induced, infection-related or malignancy-related neutropenia. An accurate quantification of dysplasia should be performed in order to distinguish RT or RN from the provisional entity named idiopathic cytopenia of unknown significance (ICUS). Cytogenetic analysis, and possibly in the future somatic mutation analysis (of genes most frequently mutated in MDS), and flow cytometry analysis aberrant antigen expression on myeloid cells may help in this differential diagnosis. Importantly, we and others found that, while isolated neutropenia and thrombocytopenia are not rare in MDS, those patients can generally be classified (according to WHO 2008 classification) as refractory cytopenia with multilineage dysplasia or refractory anemia with excess blasts, while RT and RN (according to WHO 2008) are quite rare. These results suggest in particular that identification of RT and RN as distinct entities could be reconsidered in future WHO classification updates.

In MDS Del(5q), Factors Other Than Age and Sex Distribution Contribute to the Prognostic Advantage, Which Diminishes over Time

IntroductionThe WHO classification of myelodysplastic syndromes defines several subtypes. Prognosis of MDS del(5q) is considered favourable, which is reflected in the WHO prognostic scoring system (WPSS). Compared to other subtypes like refractory cytopenia with unilineage dysplasia (RCUD), refractory cytopenia with multilineage dysplasia (RCMD) and refractory anaemia with ringed sideroblasts (RARS), MDS del(5q) patients are however younger and the percentage of female patients is higher.Thus, the aim of this work was to determine to which extent the prognostic advantage of MDS del(5q) over other MDS subtypes is due to the more favourable age and sex distribution in this group.Patients and MethodsBetween 1982 and 2013, 5383 patients were included in the Duesseldorf MDS registry. We identified 2011 patients who had no more than 5% blasts in the bone marrow and were classified either as RCUD, RCMD, RARS or MDS del(5q).Besides WHO type and blast count, sex, age at diagnosis as well as the classification into primary and secondary MDS were regarded. 99 patients were omitted from the analysis due to missing values. Thus, the final data set contained 1912 patients, of whom 1576 patients had received best supportive care only as well as 336 patients who had received one or more therapies during the observation period, the most frequent being lenalidomide.Kaplan-Meier curves and Cox proportional hazards models were estimated for mortality. Interaction effects between WHO type and sex were tested. Models were compared using the Akaike information criterion (AIC). Additionally “progression to AML” was analysed with the competing event “death without progression”.ResultsAccording to the WHO criteria, 125 (7%) were classified as MDS del(5q), 265 patients (14%) as RCUD, 206 (11%) as RARS and 1316 (69%) as RCMD. Median age was 68 years (range: 32-89) for MDS del(5q), 70 years (17-91, RCUD), 73 years (18-88, RARS) and 71 years (18-93, RCMD). In our sample 911 patients (48%) were women, but with considerable differences between the different WHO subtypes (MDS del(5q):67%, RCMD: 44%). The median observation time was 9.1 years (range: 0.01-31 years). During this period, 1312 deaths were observed, 194 patients progressed to AML.Median survival was 6.17 years (95%-CI: [5.07-8.09]) for MDS del(5q) patients, 5.20 years (95%-CI: [4.41-5.98]) for those with RARS, 4.48 years (95%-CI: [3.70-5.49]) for RCUD patients and 2.96 years (95%-CI: [2.64-3.22]) for those with RCMD. Survival curves gave strong hints of non-proportionality.Thus we had to incorporate a time-dependent effect for the WHO type in the multivariate cox model considering all covariates mentioned above, Best results were achieved with an effect of the type β1+β2*log(time). Among blasts and type of MDS (primary vs. secondary), age (hazard ratio (HR): 1.040, 95%-confidence interval (CI): [1.035-1.046]) and sex (HR: 0.856, 95%-CI: [0.766-0.956] for women vs. men) remained in the model as well. No interactions between age, sex and WHO type were found.According to this model, at diagnosis HRs were 1.812 (95%-CI: [1.199-2.740], RCUD vs MDS del(5q)), 1.167 (95%-CI: [0.742-1.837], RARS vs MDS del(5q)) and 2.284 (95%-CI: [1.550-3.366], RCMD vs MDS del(5q)). Interestingly this advantage of MDS del(5q) disappeared over time, the hazard ratio became 1 after about 3.5 years for RCUD, 7.2 years for RCMD.Regarding progression to AML no time-dependent coefficients were needed and we did not find any significant differences concerning the WHO subtypes. Age and sex did not seem to play a major role. The risk of progression to AML was mainly determined by the blast count and the type of MDS (primary vs. secondary).ConclusionsOur analyses indicate that the higher survival probabilities are not only due to the different age and sex distributions. However, we found strong hints that the survival advantage of MDS del(5q) is vanishing over time, especially in comparison to RCUD and RCMD. For the next revision of the WPSS it should be discussed to introduce a time-dependent component at least for the different WHO subtypes, since it seems likely that the hazard ratios are not constant over time. DisclosuresNo relevant conflicts of interest to declare.

Interobserver variance in myelodysplastic syndromes with less than 5 % bone marrow blasts: unilineage vs. multilineage dysplasia and reproducibility of the threshold of 2 % blasts.

Previous studies have shown the reproducibility of the 2008 World Health Organization (WHO) classification in myelodysplastic syndromes (MDS), especially when multilineage dysplasia or excess of blasts are present. However, there are few data regarding the reproducibility of MDS with unilineage dysplasia. The revised International Prognostic Scoring System R-IPSS described two new morphological categories, distinguishing bone marrow (BM) blast cell count between 0-2 % and >2- < 5 %. This distinction is critical for establishing prognosis, but the reproducibility of this threshold is still not demonstrated. The objectives of our study were to explore the reliability of the 2008 WHO classification, regarding unilineage vs. multilineage dysplasia, by reviewing 110 cases previously diagnosed with MDS, and to study whether the threshold of ≤2 % BM blasts is reproducible among different observers. We used the same methodology as in our previous paper [Font et al. (2013) Ann Hematol 92:19-24], by encouraging investigators to include patients with <5 % BM blasts. Samples were collected from 11 hospitals and were evaluated by 11 morphologists. Each observer evaluated 20 samples, and each sample was analyzed independently by two morphologists. Discordance was observed in 36/108 suitable cases (33 %, kappa test 0.503). Diagnosis of MDS with unilineage dysplasia (refractory cytopenia with unilineage dysplasia (RCUD), refractory anemia with ring sideroblasts (RARS) or unclassifiable MDS) was assessed in 33 patients, by either of the two observers. We combined this series with the cases with RCUD or RARS included in our 2013 paper, thus obtaining 50 cases with unilineage dysplasia by at least one of the observers. The whole series showed very low agreement regarding RCUD (5/23, 21 %) and RARS (5/28, 18 %). Regarding BM blast count, the threshold of ≤2 % was not reproducible (discordance rate 32/108 cases, kappa test 0.277). Our study shows that among MDS WHO 2008 categories, interobserver discordance seems to be high in cases with unilineage dysplasia. We also illustrate that the threshold of ≤2 % BM blasts as settled by the R-IPSS may be not easy to reproduce by morphologists in real practice.

Inter-Observer Discordance With The Diagnosis Of Myelodysplastic Syndromes With Less Than 5% Bone Marrow Blasts: Unilineage Vs Multilineage Dysplasia and Reproducibility Of The Threshold Of 2% Blasts

IntroductionPrevious studies have shown the reproducibility of the 2008 WHO classification in myelodysplastic syndromes (MDS), especially in the categories refractory cytopenia with multilineage dysplasia (RCMD) and refractory anemia with excess blasts (RAEB) type 1 and type 2. However, there is few data regarding the reproducibility of the diagnosis of MDS with unilineage dysplasia. Recently, two new morphological categories have been included in the R-IPSS, distinguishing the BM blast cell count between 0 and 2%, and >2 - <5%. This distinction is critical for establishing prognosis, but the reproducibility of this threshold is still not demonstrated. Objectives1-To explore the reliability of the 2008 WHO classification of MDS in cases without excess of marrow blasts (<5%), regarding unilineage vs multilineage dysplasia. 2- To study if the threshold of 2% marrow blasts is reproducible among different observers. Methods110 samples from patients previously diagnosed with MDS according to 2008 WHO classification were included. The design of the study recommended include preferentially patients with <5% BM blasts, encouraging the inclusion of cases with unilineage dysplasia, but the proportion of samples from each category was not predefined. Specimens were collected from 11 hospitals and were evaluated by 11 morphologists. Each observer evaluated 20 samples, and each sample was analyzed independently by two morphologists. The second observer was blinded to the clinical and laboratory data, except for the peripheral blood (PB) counts. The interobserver concordance was evaluated using the Cohen kappa test. ResultsFinally 108 samples were considered suitable by the second observers. Regarding 2008 WHO categories, 7 cases had refractory cytopenia with unilineage dysplasia (RCUD), 15 refractory anaemia with ring sideroblasts (RARS), 73 RCMD (including 33 with RS), 9 MDS with del(5q), 2 RAEB-1 and 2 MDS -unclassified (MDS-U). The MDS–U included the only case of the series with 1% blasts in the PB and one case with unilineage dysplasia and pancytopenia. Discordance was observed in 36/108 cases (33%). There was very good correlation in identifying the threshold of 15% RS (kappa test=0.755). The inter-observer concordance was very good regarding MDS with del(5q) (8/9, 88%), and RCMD (56/73 cases, 77%). One of the two cases of RAEB-1 was recognized by the second observer, and the only case with 1% PB blasts was also identified. Despite the bias of selecting cases with<5% BM blasts, there were 5 cases of RCMD classified as RAEB-1 by the second observers. The new morphological categories using the threshold of 2% BM blasts were not reproducible (discordance rate 31/108 cases, k test=0.279).Diagnosis of MDS with unilineage dysplasia (RCUD, or RARS, or MDS-U) was assessed in 33 patients, by either of the two observers. However, they only found concordance in 3/15 cases originally diagnosed with RARS (20%) and in 3/7 with RCUD (42%). ConclusionsAmongst MDS WHO 2008 categories, inter-observer discordance seems to be high regarding cases with unilineage dysplasia.The proposed 2% cutoff BM blasts as settled by the R-IPSS may be not easy to reproduce by morphology in real practice. MDS-U category could be probably discarded in upcoming classifications, as different groups like ours proves it to be marginal. Disclosures:No relevant conflicts of interest to declare.

Chronic Idiopathic Neutropenia In Adults: Clinical Features In a 4-Year Prospective Study

Chronic idiopathic neutropenia (CIN) is a rare acquired hematological condition, defined by an absolute neutrophil count (ANCs) lower than 1.8 x103/µL in white and 1.5 x103/µL in black people for more than 3 months, either in the absence or in the presence of anti-neutrophils antibodies (autoimmune forms). CIN is usually diagnosed after the exclusion of congenital and secondary forms. The former are usually marked by frequent and severe infections, that occur early in life, and by and increased risk of evolution to acute myeloid leukemia or myelodisplastic syndromes. In this prospective study we followed up 56 patients with CIN (21 males and 35 females, median age 55 years, range 25-86 years) for a median time of 48 months from January 2009 (10 patients had a previous follow-up of 8 years and 2 of 10 years), focusing on 1) severity of neutropenia, 2) ANCs variations (by general estimating equations GEE models), 3) positivity for anti-neutrophil antibodies (by direct and indirect granulocyte immunofluorescence test), 4) bone marrow features, 5) incidence of infectious episodes, and 6) evolution to definite clonal hematologic diseases (hairy cell leukemia HCL, chronic expansion of NK cells and myelodisplastic syndrome MDS). The mean ANCs were stably under the normal range (1.5-6.5 x103/µL) at all the time points considered; by GEE analysis, a great inter-subject variability was observed during the follow-up (p=0.012), whereas no significant intra-subject variations were found. Considering the severity of neutropenia, 21 patients (47%) showed neutrophils lower than 1x103/µL at enrollment (median 0.49 x103/µL, range 0.1-0.969 x103/µL), and 8 cases <0.5 x103/µL. The mean ANCs observed during the follow up were significantly lower in males than in females (p=0.023) and in cases with mild splenomegaly, although not significantly (11 cases, 20%, mean maximal diameter 11,4 cm by ultrasonography), independently from gender (multivariate analysis). Anti-neutrophil antibodies were detected in 19/56 patients (34%), and mean ANCs values over the follow up were significantly lower in positive versus negative cases (p=0.027). Lymphocyte values greater than the upper normal value of our series (3.4 x103/µL) were observed in 5/56 patients (9%). By peripheral blood immunophenotyping (N=23), 13 (56.5%) patients displayed absolute NK+ cells greater than 0.2 x103/mL (normal NK cut-off value), but all under below 2 x103/µL. Bone marrow evaluation was performed in 27 patients: median cellularity was 35% (range 13-75), and 10/27 (37%) displayed a value lower than 25% (threshold for hypocellularity in aplastic anemia); 19/27 (70%) showed some dysplastic cells, even if less than 10% dysplastic cells and without coexistent MDS-related karyotype; cytogenetic was normal in 24 cases (89%), while 3 males, all older than 60 years, displayed a 45, X0 karyotype (7, 6 and 3 metaphases respectively. Finally, 10 patients (18%) showed monocytosis, and 6 (10%) a MGUS. An infection needing oral antibiotic or antiviral therapy occurred in 13 patients (25%) (2 pneumonias, 7 upper respiratory tract, 3 Herpes Zoster Virus and 1 urinary tract infections), without relationship with the patient's mean ANCs value, the nadir of ANC value, nor with the presence of anti-neutrophil antibodies. During the follow-up, because of suspected progression/evolution, 14 patients were re-evaluated by bone marrow biopsy or peripheral immune-phenotyping: 4 cases were diagnosed with chronic NK expansion, 4 with HCL, and 2 with MDS, one refractory cytopenia with unilineage dysplasia (RCUD) and one with multilineage dysplasia (RCMD). No association was found between evolution and ANCs, both as values at enrolment and mean counts over the follow up, nor with gender, presence of anti-neutrophils antibodies, monocytosis, splenomegaly, electrophoresis abnormalities and infections. All 4 patients, who developed an NK-expansion, showed peripheral lymphocytes >3.4 x103/µL at enrolment (>5x103/µL in only 1 case), and 3 cases displayed increased NK cells at peripheral immune-phenotyping (p= 0.018). In conclusion, CIN in adults is a benign disease, with an infectious rate not superior to that of the general population and a great variability in ANCs values. During this prospective observation, 10 CIN patients evolved, reaching the criteria for clonal hematological diseases, suggesting that this condition deserves clinical follow up. Disclosures:No relevant conflicts of interest to declare.

Cytogenetic Analysis in Patients with Newly Diagnosed Myelodysplastic Syndromes in Southern Italy

AbstractAbstract 50623 Background:Bone marrow karyotype in myelodysplastic syndromes (MDS) is essential to define the prognosis and to guide treatment decisions, including targeted therapies. Due to the lack of an extensive national MDS registry in Italy, epidemiological data on MDS, including cytogenetics, throughout the territory is unknown. Objective:We evaluated the incidence of cytogenetic abnormalities amongst newly diagnosed MDS patients in in 2 southern Italian regions (Calabria and Puglia). Methods:A pilot project, denominated ANDROMEDA (ANalysis of cytOgenetics alteRatiOn in the MyEloDysplAstic syndromes) was developed in 17 centers to offer a service of conventional cytogenetic analysis for all consecutive patients undergoing diagnostic evaluation for cytopenia and suspected MDS between January 1 and December 31, 2011. The study conformed to the ethical standards set out in the Declaration of Helsinki and was approved by institutional review boards at each participating center. Patients were required to provide their written informed consent. Clinical characteristics of patients and bone marrow morphology, iron staining and histology were registered. Bone marrow samples were centralized for standard cytogenetic studies and fluorescence in situ hybridization to two dedicated genetics laboratories (one for each region), blind to patients' data. Results:Two hundred and thirty-five patients were evaluated and MDS diagnosis was confirmed in 220 cases (88. 3%), according to WHO criteria. The overall incidence of clonal chromosome abnormalities detected by conventional analysis was 36. 9%. Single abnormalities included +8 (13 cases, 5. 8%), del(5q) (12 cases, 5. 4%), –Y (11 cases, 5. 0%) and del(7)/-7 (4 cases, 1. 8%). Complex karyotypes were detected in 18 (8. 1%) cases. Among all cases only 10 (4. 5%) bone marrow samples were not evaluable for cytogenetic analysis. FISH revealed additional abnormalities not identified by conventional analysis only in 3 (1. 3%) out of 72 cases. Patients were classified in WHO subtypes: 39. 2% refractory cytopenia with unilineage dysplasia (RCUD), 1. 5% refractory anemia with ring sideroblasts (RARS), 32. 5% refractory cytopenia with multilineage (RCMD), 10. 8% refractory anemia with excess of blast-1 (RAEB-1), 9. 3% refractory anemia with excess of blast-2 (RAEB-2), 4. 1% MDS with deletion 5q (MDS 5q-) and 2. 6% MDS unclassifiable (MDS-U). Conclusions:These preliminary results demonstrate that the incidence of abnormal karyotype patterns and WHO subgroups in MDS patients in Southern Italy is comparable with that described in other geographical areas. It is confirmed that conventional cytogenetic analysis is a standard in the diagnostic workup of MDS of patients with a suspected myeloid malignancy in order to identify primary abnormalities and prognostic models. Disclosures:No relevant conflicts of interest to declare.

Cytogenetic Analysis in Patients with Newly Diagnosed Myelodysplastic Syndromes in Southern Italy

AbstractAbstract 5200 Background:Bone marrow karyotype in myelodysplastic syndromes (MDS) is essential to define the prognosis and to guide treatment decisions, including targeted therapies. Due to the lack of an extensive national MDS registry in Italy, epidemiological data on MDS, including cytogenetics, throughout the territory is unknown. Objective:We evaluated the incidence of cytogenetic abnormalities amongst newly diagnosed MDS patients in in 2 southern Italian regions (Calabria and Puglia). Methods:A pilot project, denominated ANDROMEDA (ANalysis of cytOgenetics alteRatiOn in the MyEloDysplAstic syndromes) was developed in 17 centers to offer a service of conventional cytogenetic analysis for all consecutive patients undergoing diagnostic evaluation for cytopenia and suspected MDS between January 1 and December 31, 2011. The study conformed to the ethical standards set out in the Declaration of Helsinki and was approved by institutional review boards at each participating center. Patients were required to provide their written informed consent. Clinical characteristics of patients and bone marrow morphology, iron staining and histology were registered. Bone marrow samples were centralized for standard cytogenetic studies and fluorescence in situ hybridization to two dedicated genetics laboratories (one for each region), blind to patients' data. Results:Two hundred and thirty-five patients were evaluated and MDS diagnosis was confirmed in 220 cases (88. 3%), according to WHO criteria. The overall incidence of clonal chromosome abnormalities detected by conventional analysis was 36. 9%. Single abnormalities included +8 (13 cases, 5. 8%), del(5q) (12 cases, 5. 4%), –Y (11 cases, 5. 0%) and del(7)/-7 (4 cases, 1. 8%). Complex karyotypes were detected in 18 (8. 1%) cases. Among all cases only 10 (4. 5%) bone marrow samples were not evaluable for cytogenetic analysis. FISH revealed additional abnormalities not identified by conventional analysis only in 3 (1. 3%) out of 72 cases. Patients were classified in WHO subtypes: 39. 2% refractory cytopenia with unilineage dysplasia (RCUD), 1. 5% refractory anemia with ring sideroblasts (RARS), 32. 5% refractory cytopenia with multilineage (RCMD), 10. 8% refractory anemia with excess of blast-1 (RAEB-1), 9. 3% refractory anemia with excess of blast-2 (RAEB-2), 4. 1% MDS with deletion 5q (MDS 5q-) and 2. 6% MDS unclassifiable (MDS-U). Conclusions:These preliminary results demonstrate that the incidence of abnormal karyotype patterns and WHO subgroups in MDS patients in Southern Italy is comparable with that described in other geographical areas. It is confirmed that conventional cytogenetic analysis is a standard in the diagnostic workup of MDS of patients with a suspected myeloid malignancy in order to identify primary abnormalities and prognostic models. Disclosures:No relevant conflicts of interest to declare.

P-04 ABO MAJOR INCOMPATIBILITY IN ALLOGENEIC BONE MARROW TRANSPLANTATION: RBC REMOVAL WITH COMTEC CELL SEPARATOR

The Myelodysplastic syndrome (MDS) is characterized by peripheral blood cytopenia and dysplastic changes of one or more cell lines in the bone marrow. There is an increased risk of transformation to acute myelogenous leukemia in time. A significant proportion of the patients require blood product due to severe anemia and/or thrombocytopenia. Our objective in this retrospective study was, to determine the characteristics of patients with respect to blood product requirement and to determine whether there was a change in transfusion practice with time in patients who require blood product transfusion. We analyzed a total 35 (14 Female/21 Male) patients who were diagnosed with MDS from 2002 through 2012 whose data were also available in the blood bank of Gazi University Hospital. We used WHO classification for determination MDS subtype and International Prognostic Scoring System (IPSS) for risk-stratification. The median age was 66.0 (range: 22–88). The most common subtypes were refractory cytopenia with unilineage dysplasia (RCUD) (48.6%), Refractory anemia with excess blasts (RAEB-1) (14.3%) RAEB-2 (14.3%) and chronic myelomonocytic leukemia (CMML-1) (14.3%). The riskstratification for 33 patients was low-risk in30.3%, intermediate-1 in 60.6% and intermediate-2 in9.1%. Among the 25 patients whose molecular studies (FISH) was available, 1 patient had 5q deletion, 1 patient had 7q deletion whereas the others were normal Fifteen patients required treatment and received one of the drugs 5-azacytidine, thalidomide or lenalidomide). Sixty three percent of the patients required transfusion among which 86.4% received packed red blood cells. 45.5% received platelets. Eleven patients were followed a minimum of 24 months. The transfusion requirement of the patients in the first and second 12 month interval were similar. The transfusion requirement was also similar in the first and second year with respect to the MDS subtype, IPSS and treatment status. Median overall survival was 40.5 months (range: 23–79) and median progression free survival was 33.2 months (range 21–65). It might be expected that transfusion requirement to increase with time due to disease progression. Whereas our data show that the transfusion requirement of the patients remained stable in 2 years follow-up. The new generation agents might have delayed the disease progression and increase in transfusion requirement might have been observed with a longer follow up. P-04 ABO MAJOR INCOMPATIBILITY IN ALLOGENEIC BONE MARROW TRANSPLANTATION: RBC REMOVAL WITH COMTEC CELL SEPARATOR P. Accorsi, R. Giancola, C. Passeri, A. Iacone. Dept. of Transfusion Medicine, Pescara Civil Hospital, Dept. of Transfusion Medicine, Pescara Civil Hospital, Italy

P-03 THE PATTERN OF TRANSFUSION REQUIREMENT IN A GROUP OF PATIENTS WITH MYELODYSPLASTIC SYNDROME IN THE ERA OF NEW GENERATION AGENTS

The Myelodysplastic syndrome (MDS) is characterized by peripheral blood cytopenia and dysplastic changes of one or more cell lines in the bone marrow. There is an increased risk of transformation to acute myelogenous leukemia in time. A significant proportion of the patients require blood product due to severe anemia and/or thrombocytopenia. Our objective in this retrospective study was, to determine the characteristics of patients with respect to blood product requirement and to determine whether there was a change in transfusion practice with time in patients who require blood product transfusion. We analyzed a total 35 (14 Female/21 Male) patients who were diagnosed with MDS from 2002 through 2012 whose data were also available in the blood bank of Gazi University Hospital. We used WHO classification for determination MDS subtype and International Prognostic Scoring System (IPSS) for risk-stratification. The median age was 66.0 (range: 22–88). The most common subtypes were refractory cytopenia with unilineage dysplasia (RCUD) (48.6%), Refractory anemia with excess blasts (RAEB-1) (14.3%) RAEB-2 (14.3%) and chronic myelomonocytic leukemia (CMML-1) (14.3%). The riskstratification for 33 patients was low-risk in30.3%, intermediate-1 in 60.6% and intermediate-2 in9.1%. Among the 25 patients whose molecular studies (FISH) was available, 1 patient had 5q deletion, 1 patient had 7q deletion whereas the others were normal Fifteen patients required treatment and received one of the drugs 5-azacytidine, thalidomide or lenalidomide). Sixty three percent of the patients required transfusion among which 86.4% received packed red blood cells. 45.5% received platelets. Eleven patients were followed a minimum of 24 months. The transfusion requirement of the patients in the first and second 12 month interval were similar. The transfusion requirement was also similar in the first and second year with respect to the MDS subtype, IPSS and treatment status. Median overall survival was 40.5 months (range: 23–79) and median progression free survival was 33.2 months (range 21–65). It might be expected that transfusion requirement to increase with time due to disease progression. Whereas our data show that the transfusion requirement of the patients remained stable in 2 years follow-up. The new generation agents might have delayed the disease progression and increase in transfusion requirement might have been observed with a longer follow up. P-04 ABO MAJOR INCOMPATIBILITY IN ALLOGENEIC BONE MARROW TRANSPLANTATION: RBC REMOVAL WITH COMTEC CELL SEPARATOR P. Accorsi, R. Giancola, C. Passeri, A. Iacone. Dept. of Transfusion Medicine, Pescara Civil Hospital, Dept. of Transfusion Medicine, Pescara Civil Hospital, Italy

Prediction of Progression from Refractory Cytopenia with Unilineage Dysplasia by Analysis of Bone Marrow Blast Cell Composition

A retrospective analysis of 71 patients newly diagnosed with refractory cytopenia with unilineage dysplasia (RCUD) revealed that 12 developed refractory anemia with an excess of blasts or acute myeloblastic leukemia. Before the diagnosis of RCUD was made, phenotypes of cells in the bone marrow (BM) blast region were analyzed using flow cytometry. Patients with RCUD were divided into two groups ; those with no progression (Group A) and those with disease progression later on (Group B). The cell composition in the BM blast region differed significantly between the groups : Group A showed higher percentages of B lymphoid cells but lower percentages of myeloid cells. A cut-off value of 20 for the CD33/CD10 ratio in the BM blast region clearly separated Group A from Group B. These results suggest that cell composition in the BM blast region evaluated by flow cytometry may indicate the progression of RCUD.

Next-Generation Deep-Sequencing Enables a Quantitative Monitoring of RUNX1 Mutations in 534 Patients with Myelodysplastic/Myeloproliferative Neoplasms and Myelodysplastic Syndromes

Abstract 2792 Introduction:Somatic mutations of key candidate genes have gained interest as biomarkers predicting poor survival in myelodysplastic/myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS). RUNX1 (runt-related transcription factor 1) deregulations constitute such a disease-defining molecular aberration and are usually tested applying a combination of denaturing high-performance liquid chromatography and direct Sanger sequencing. Patient-specific RUNX1 mutations were proposed to represent clinically useful molecular alterations to follow disease progression from MDS to s-AML. Study design: Using genomic DNA obtained from mononuclear cells a next-generation amplicon deep-sequencing (NGS) assay targeting the complete coding region of RUNX1 was developed on a longitudinal series of 116 retrospective samples obtained from 25 patients collected between 11/2005 and 6/2010 (454 Life Sciences, Branford, CT). Subsequently, this assay was applied to characterize an unselected prospectively collected MPN/MDS patient cohort during their course of disease. Results: Here, we present analyses on a cohort of 534 patients (females: 200; males 334). The median age was 72.0 years (25.2–95.7 years). The cohort included 149 chronic myelomonocytic leukemias (CMML), 11 cases with 5q- syndrome, 10 cases with refractory cytopenia with unilineage dysplasia (RCUD), 15 cases with refractory anemia with ring sideroblasts (RARS), 105 cases with refractory cytopenia with multilineage dysplasia (RCMD), 135 cases with refractory anemia with excess blasts-1 (RAEB-1), 87 cases with refractory anemia with excess blasts-2 (RAEB-2), and 22 cases with t-MDS, respectively. In total, 130 RUNX1 mutations were observed in 17.8% (95/534) of these patients. The mutational clone size ranged from 1.7% to 94% and amounted to a median of 31%. In comparison to our data from an AML cohort, i.e. 460 patients at diagnosis with 112 (24.3%) cases mutated, the median clone size was about 10% lower in MPN/MDS. In detail, 74.7% (71/95) of patients harbored one mutation, whereas 25.3% (24/95) of cases harbored two (17.9%; 17/95) or >=3 (7.4%; 7/95) mutations. The 130 RUNX1 mutations were characterized as follows: 29% frame-shift mutations, 42% missense, 14% nonsense, 13% exon-skipping, and 2% in-frame insertion/deletion alterations, respectively. The following codons were recurrently mutated: Arg174 (8/95 patients; 9.4%), Arg177 (6/95 patients; 7.0%), and Arg135 (5/95 patients; 5.3%). The mutations were predominantly located in the RHD domain (55%) and TAD domain (13%) and in cases with 2 or more alterations only 15% (4/24) harbored mutations outside of these regions. In all cases with 3 concomitant mutations both domains were affected (4/4 patients). Further, cases with >1 RUNX1 mutation were more frequently observed in CMML (33.3%; 8/24 mutated), RAEB-1 (17.2%; 5/29 mutated) and RAEB-2 (34.5%, 10/29 mutated) as compared to other disease groups, respectively. In subsequent serial analyses including 56 samples from 22 cases the amplicons carrying the respective known alteration were analyzed with increased coverage for disease status monitoring (in median 833 reads/amplicon were sequenced; leading to a sensitivity of ∼1:800). With a median time span of 2.5 months between the molecular analyses a total of 2 to 4 samples per patient were analyzed. In 5/22 patients, this assay then allowed to monitor the treatment success of allogeneic stem cell transplantation: in 3 cases the mutations known before transplantation became undetectable; in 2 cases the same mutated clones still remained detectable at a level of 0.2% and 23%, respectively. Further, in 17 patients quantitative assessment of mutated RUNX1 read counts was used to monitor stable disease (n=12) or allowed to follow an increasing clone size in 3 patients that progressed into s-AML (39% -> 53% increase; 31% -> 42% increase; 7% -> 37% increase). Summary: Unbiased techniques such as deep-sequencing provide the required diagnostic specificity and sensitivity to enable classification and individualized monitoring of disease progression. We here demonstrate that amplicon-based NGS is a suitable method to accurately detect and quantify the broad spectrum of molecular RUNX1 aberrations with high sensitivity. It is therefore suitable for therapy guidance. Disclosures:Kohlmann:MLL Munich Leukemia Laboratory: Employment; Roche Diagnostics: Honoraria. Grossmann:MLL Munich Leukemia Laboratory: Employment. Harbich:MLL Munich Leukemia Laboratory: Employment. Dicker:MLL Munich Leukemia Laboratory: Employment. Nadarajah:MLL Munich Leukemia Laboratory: Employment. Alpermann:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

NAD(P)H: Quinone Oxidoreductase 1 Deficiency Conjoint with Marginal Vitamin C Deficiency Causes Cigarette Smoke Induced Myelodysplastic Syndromes

BackgroundThe etiology of myelodysplastic syndromes (MDS) is largely unknown. Exposure to cigarette smoke (CS) is reported to be associated with MDS risk. There is inconsistent evidence that deficiency of NAD(P)H-quinone: oxidoreductase 1 (NQO1) increases the risk of MDS. Earlier we had shown that CS induces toxicity only in marginal vitamin C-deficient guinea pigs but not in vitamin C-sufficient ones. We therefore considered that NQO1 deficiency along with marginal vitamin C deficiency might produce MDS in CS-exposed guinea pigs.Methodology and Principal FindingsHere we show that CS exposure for 21 days produces MDS in guinea pigs having deficiency of NQO1 (fed 3 mg dicoumarol/day) conjoint with marginal vitamin C deficiency (fed 0.5 mg vitamin C/day). As evidenced by morphology, histology and cytogenetics, MDS produced in the guinea pigs falls in the category of refractory cytopenia with unilineage dysplasia (RCUD): refractory anemia; refractory thrombocytopenia that is associated with ring sideroblasts, micromegakaryocytes, myeloid hyperplasia and aneuploidy. MDS is accompanied by increased CD34(+) cells and oxidative stress as shown by the formation of protein carbonyls and 8-oxodeoxyguanosine. Apoptosis precedes MDS but disappears later with marked decrease in the p53 protein. MDS produced in the guinea pigs are irreversible. MDS and all the aforesaid pathophysiological events do not occur in vitamin C-sufficient guinea pigs. However, after the onset of MDS vitamin C becomes ineffective.Conclusions and SignificanceCS exposure causes MDS in guinea pigs having deficiency of NQO1 conjoint with marginal vitamin C deficiency. The syndromes are not produced in singular deficiency of NQO1 or marginal vitamin C deficiency. Our results suggest that human smokers having NQO1 deficiency combined with marginal vitamin C deficiency are likely to be at high risk for developing MDS and that intake of a moderately large dose of vitamin C would prevent MDS.

The Risk of Secondary Myelodysplastic Syndrome/Acute Leukemia Following High-Dose Yttrium-90 Ibritumomab Tiuxetan Is Analogous to That Observed Following High-Dose Chemotherapy: a Matched-Pair Analysis In Non-Hodgkin Lymphoma Patients.

AbstractAbstract 1289 Introduction:Myeloablative doses of Yttrium-90 (90Y)-Ibritumomab Tiuxetan combined with tandem autologous peripheral blood stem cell (PBSC) support can be safely administered to patients aged up to 76 years (Devizzi L et al, J Clin Oncol 2008). Whether marrow exposure to myeloablative doses of radiolabelled antibodies (hd-radio-immunotherapy) could increase the risk of secondary myelodysplastic syndrome and acute leukemia (sMDS/AL) remains a matter of concern. Therefore, we prospectively investigated by means of a longitudinal study the incidence of sMDS/AL in a cohort of high-risk non-Hodgkin lymphoma (NHL) patients receiving hd-radio-immunotherapy. The cumulative incidence of sMDS/AL in the study group was compared with that observed in a historical group of patients autografted following chemotherapy-based myeloablative conditioning. Additionally, to further investigate marrow damage induced by hd-radio-immunotherapy, hematopoietic and stromal progenitors, as well as telomere length (TL) were assessed. Patients and Methods:From July 2004 through December 2007, 53 relapsed/refractory (n= 36) or de novo high-risk (n= 17) NHL patients (median age, 64 years; range, 26 – 76 years) received a high-dose sequential (HDS) chemotherapy program, including a myeloablative phase with 90Y-Ibritumomab Tiuxetan (1.2 mCi/kg body weight). Patients were monitored for frequency of colony-forming cells (CFCs), cytogenetic and TL analysis. Bone marrow (BM) samples were collected prior to hd-radio-immunotherapy, every six months for two years and annually thereafter. The study was approved by the Institutional Ethical Committee and written informed consent was obtained from each patient. The study group included 29 patients with aggressive lymphoma (diffuse large B-cell lymphoma, n = 19; mantle cell lymphoma, n = 8; Richter syndrome, n = 2) and 24 with indolent NHL subtypes (follicular lymphoma, n = 20; marginal zone lymphoma, n = 3; lymphocytic lymphoma, n = 1). Thirty patients were relapsed after one (n=15) or more (n=15) previous chemotherapy regimens, 6 patients were refractory and 17 patients were previously untreated with high-risk prognostic index. Pre-exposure to alkylating agent involved 68% of the patients. A historical group of 55 NHL patients who received an analogous HDS program with final chemotherapy-based autografting was used as control group. Study and control groups were pair-matched for age, gender, histological subtype, disease status at transplant and type of grafted PBSC. Results:At a median follow-up of 49 months (range, 32 – 74), 4 out of 53 patients of the study group developed sMDS/AL at 6, 12, 27 and 36 months from transplant. According to WHO criteria, refractory anemia with excess of blasts 1 (RAEB-1) was diagnosed in one patient, whereas refractory cytopenia with unilineage dysplasia (RCUD) was diagnosed in the other three cases, with acute leukemia transformation being observed in two patients at 12 and 18 months after initial detection of abnormal cytogenetics, respectively. The cumulative incidence of sMDS/AL resulted of 8.29% at 5-years. An analogous 5-year cumulative incidence of 8.05% was observed in the historical control group autografted following a chemotherapy-based conditioning. Radioimmunotherapy-treated patients showed a significant but transient decrease in granulocyte-macrophage colony forming unit (CFU-GM) at 6 months after transplant, with recovery to baseline values at 12 months. Multilineage colony-forming units (CFU-Mix), erythroid burst-forming units (BFU-E) and fibroblast CFU (CFU-F) were not show significantly affected over time. In contrast, a progressive and significant decrease in BM TL was evident from 12 months after transplant. Conclusion:In our series of elderly NHL patients receiving hd-radio-immunotherapy, the incidence of sMDS/AL was found increased compared to recently reported series of younger lymphoma patients receiving chemotherapy-based conditioning. However, the increased risk of sMDS/AL was not associated with the type of myeloablative conditioning, i.e. chemotherapy vs radio-immunotherapy. Other factors may have favored the development of sMDS/AL, including advanced age at transplant, extensive pre-transplant therapy and type of reinfused PBSC. The observed progressive TL loss gives support to the concept that TL loss might be involved in sMDS/AL development. Disclosures:No relevant conflicts of interest to declare.

Differences in the distribution of subtypes according to the WHO classification 2008 between Japanese and German patients with refractory anemia according to the FAB classification in myelodysplastic syndromes

We reported the different clinical features between Japanese and German refractory anemia (RA) patients in FAB classification. We re-analyzed the clinical features by WHO classification revised in 2008. The frequencies of refractory cytopenia with unilineage dysplasia (RCUD) and myelodysplastic syndrome-unclassified (MDS-U) with pancytopenia in Japanese patients were higher than in German patients ( p < 0.001). Refractory cytopenia with multilineage dysplasia patients showed the most unfavorable prognosis in both countries. The higher frequencies of MDS-U with pancytopenia and RCUD in Japanese patients may influence the different clinical characteristics between Japanese and German FAB-RA patients.

Integrating WHO 2001–2008 criteria for the diagnosis of Myelodysplastic Syndrome (MDS): A case–case analysis of benzene exposure

We characterized the prevalence of hematopoietic and lymphoid disease for 2923 consecutive patients presenting at 29 hospitals from August 2003 to June 2007. Diagnoses were made in our laboratory using WHO criteria based on morphologic, immunophenotypic, cytogenetic, FISH and molecular data. A total of 611 subjects (322 males/289 females) were prospectively diagnosed with MDS using WHO (2001) criteria. Update and re-evaluation of cases using MDS (2008) criteria resulted in 649 MDS cases. Using WHO (2008) criteria, refractory cytopenia with multilineage dysplasia (RCMD) accounted for 68% of total cases, refractory anemia with excess blasts (RAEB), 16.3%; refractory anemia (RA), 6.5%; refractory cytopenia with unilineage dysplasia (RCUD), 4%; and MDS-unclassifiable (MDS-U), 4.5%. Subjects were administered questionnaires and information on previous disease, work histories and exposures to potential etiologic agents such as benzene (BZ) was obtained. A total of 80/649 (13.2%) were determined to have some BZ exposure. The frequency of clonal cytogenetic abnormalities in all MDS was 30%, the most common being +8 > del(20)q > del(7q) > del(5q), while the analogous frequency in BZ-exposed cases was only 24%. To further investigate the characteristics of MDS associated with BZ, we identified a subset of cases with high BZ exposure. These BZ signal cases were each matched by age and gender to two cases with no known BZ exposure. When contrasting BZ signal cases vs matched cases with no BZ exposure, we found a high odds ratio (OR) for the WHO subtype MDS-U (OR = 11.1), followed by RAEB and RCUD (OR = 1), RA (OR = 0.7) and RCMD (OR = 0.6). Multilineage dysplasia with abnormal eosinophils (MDS-Eo) was strongly associated with BZ exposure, whereas the relative risk of clonal cytogenetic abnormalities was reduced for high BZ-exposed cases (OR = 0.5). These findings are strongly indicative that MDS subtypes are influenced by BZ exposure, and taken together with previous studies, the features of MDS-Eo suggest that altered immune regulation plays a major role in the pathogenesis of MDS following chronic exposure to BZ.

Retrospective Analysis of Patients with Refractory Cytopenia with Unilineage Dysplasia.

Abstract 4847 BackgroundMyelodysplastic syndromes (MDS) are a group of clonal heterogeneous bone marrow stem cell disorders characterized by dysplastic hypercellular marrows with peripheral cytopenias. Accurate diagnosis and classification are essential for subgroup identification and prognostic assessment of patients with MDS. Classification systems such as the World Health Organization (WHO) classification are widely used but do not always provide sufficient prognostic information. So WHO improved the classification systems last year(2008). The major change was that refractory anemia (RA) was substituted by refractory cytopenia with unilineage dysplasia (RCUD). The aim of this study was to apply the new WHO classification to re-evaluate MDS with RA. MethodsMDS patients with RA diagnosed between 2000 and 2008 were retrospectively reclassified with WHO criteria (2008). ResultsAccording to the new WHO classification, RCUD is intended to encompass those myelodysplastic syndromes (MDS) which present with a refractory cytopenia with unilineage dysplasia and includes refractory anemia (RA), refractory neutropenia (RN) and refractory thrombocytopenia (RT), so in 34 cases diagnosed as RA, 12 cases (12/34,35%) still pertained to RA, 19 cases (56% ) to RN and 3 (9%) cases to RT. IPSS showed 94% of RCUD cases categorized as low or intermediate-I risk. The median survival of patients with RCUD was 84 months. ConclusionsRA is the main subtypes of RCUD. Understanding the clinical features of RCUD accurately is helpful to determine the right subtype of RCUD. The new WHO classification system was improved to provide better diagnostic criteria. DisclosuresNo relevant conflicts of interest to declare.

Survival, Prognostic Factors, and Rates of Leukemic Transformation in a Multicenter Study of 303 Untreated Patients with MDS and Del(5q).

Abstract 945In 2001, the WHO defined the category MDS with del(5q) due to unique cytogenetic, morphologic, hematologic, clinical, prognostic and therapeutic features. The survival of these patients, as well as patients with refractory cytopenia with unilineage dysplasia (RCUD) and refractory anemia with ring sideroblasts is favorable in comparison to other MDS types. Data on disease progression to a more advanced MDS category or to acute leukemia (AML) are sparse and have not been examined in detail. In order to address this issue we collated data of all patients with MDS and del(5q) characterized by low or intermediate-1 IPSS risk score that had been included into various collaborating MDS registries. Patients were followed from diagnosis and data on cell counts, transfusion dependency, and MDS progression were documented. No patients received treatment other than best supportive care. The status of 62 patients was censored at the time of the initiation of Lenalidomide therapy. AML progression was defined as >20% marrow blasts. Estimates of survival probability were calculated with the Kaplan-Meier method. The cumulative incidence of progression to AML was calculated both with the Kaplan-Meier method and with the competing risk method where “death without progression to AML” is considered as competing event, not as censoring. For both events the cumulative incidences are estimated simultaneously. This method has the advantage that it takes into account that there is a difference between end of follow-up and death. Depending on the number of competing events, the curves are lower than those calculated with the Kaplan-Meier estimator.We identified 303 patients, median age at diagnosis 65 years (28-91), 71% were females. Median follow up time was 3 years. Median survival was 71.5 months. Patients with del(5q) as a sole chromosomal aberration had a median survival of 73 months as compared to 19.3 months in patients with more than 1 additional aberrations. Patients who had red cell transfusion need at diagnosis had a median survival of 39 months vs. 97 months in transfusion independent patients (p=0.00005). Transfusion need at diagnosis was the most important parameter for survival. Patients in the WPSS very low risk group had a median survival of 107 months, as compared to 73 and 56 months in the low and intermediate risk group and 37 months in the high risk group.44 of the 303 patients (15%) progressed to AML (>20% marrow blasts). The cumulative AML progression rate calculated with the Kaplan-Meier method was 7% at 2 years and 18.2% at 5 years. The cumulative risk of AML progression calculated with the competing risk method was 6.6% at 2 years and 15.1% at 5 years. Factors associated with the risk of AML transformation were intermediate-I IPSS risk and high risk WPSS score, marrow blast count >5%, and red-cell transfusion need at diagnosis. Survival and progression rates did not differ among the participating centers.In conclusion, survival of patients with MDS and del(5q) is high and is comparable to patients with RCUD and RARS, but is associated with a risk of AML-transformation similar to RCMD without del(5q). Further cytogenetic and molecular studies are warranted in order to identify patients at greater risk of progression. Disclosures:Germing:Novartis, Celgene: Honoraria, Research Funding. Lauseker:Celgene: Research Funding. Hildebrandt:Celgene: Research Funding. Symeonidis:Celgene: Research Funding. Cermak:Celgene: Research Funding. Pfeilstöcker:Celgene: Research Funding. Nösslinger:Celgene: Research Funding. Sekeres:Celgene: Research Funding. Maciejewski:Celgene: Research Funding. Haase:Celgene: Research Funding. Schanz:Celgene: Research Funding. Seymour:Celgene: Research Funding. Weide:Celgene: Research Funding. Lübbert:Celgene: Research Funding. Platzbecker:Celgene: Research Funding. Valent:Celgene: Research Funding. Götze:Celgene: Research Funding. Stauder:Celgene: Research Funding. Blum:Celgene: Research Funding. Kreuzer:Celgene: Research Funding. Schlenk:Celgene: Research Funding. Aul:Celgene: Research Funding. Kündgen:Celgene: Research Funding. Hasford:Celgene: Research Funding. Giagounidis:Celgene: Research Funding.