Poster Presentations – 12 th International Symposium on Myelodysplastic Syndromes / Leukemia Research 37 S1 (2013) S1–S117 S57 Materials and Methods: Eighty patients with cytopenias, cytoge- netic abnormalities without dysplasia were identified. Thirty were retained for our study: 5 with +8, 9 with del(20q), and 16 -Y. Results: Patients characteristics were as follow, 26 were male, me- dian age: 73.5 years (50-92), and 20 had oncologic history. Surpris- ingly we found 6 NHL, 3 Multiple myelomas, 4 CLL and 1 CML. Mar- row evaluation was performed in 5 pts because of persistent cytope- nia during chemotherapy. Marrow fibrosis was present in two pa- tients and in two other patients we found NHL and CLL infiltration. The evolution to MDS was seen in 1 pt who underwent allogeneic bone marrow transplantation (BMT). Median age for the 16 patients who lost Y was 75 y (60-85). They had also active CLL for 3 pts, MM for 1 pt, 1 low grade NHL and 4 had an history of other cancer. The IPSS/IPSS-R score were low for 15pts or int-1 for 1 pt and very low in 14 pts and low in 2pts. Median survival was 35 months (13-57). No progression to AML was seen for this group. The median age for the del (20q) group (n= 9, 8M/1F) was 76.5y (56-92). The IPSS/IPSS-R score were low for 4 pts and int1 in 5 pts and very low in 7 pts, low in 1 pt and intermediate in 1 pt. The median survival was 21 months (1-43). For trisomy 8 (n: 5, 3M/2F), the median age was 65y (50-84). The IPSS/IPSS-R score were int-1 for all 5 pts and low in 4 pts and intermediate in 1 pt. The median survival was 22 months (15-31) Conclusions: Cytogenetic have a major role in the diagnosis of MDS, particularly in the absence of cytopenias. It’s important to consider the diagnosis of MDS in the presence of -Y, +8, del (20q) regarding the prognosis and survival of these patients. In our series, despite low score IPSS or IPSS-R, survival remain worse than expected, perhaps because of other tumor or chemotherapy related effects. P-078 Flow cytometry has a high negative predictive value for excluding MDS in patients with cytopenia and indeterminate cytomorphology and cytogenetics E.M.P. Cremers , T.M. Westers, C. Alhan, M.J. Wondergem, C. Cali, C.W.M. Schouten, G.J. Ossenkoppele, A.A. Van de Loosdrecht. Hematology, VU Cancer Center Amsterdam, Amsterdam, Netherlands Background: Myelodysplastic syndromes (MDS) constitute a hetero- geneous group of hematopoietic stem cell disorder, characterized by ineffective hematopoiesis resulting in cytopenias and variable risk of acute myeloid leukemia. Introduction: Discrimination between MDS and non-clonal causes of cytopenia is regularly based on cytomorphology (CM) and cytoge- netic analysis (CG) and can be challenging when major morphologic dysplastic features or karyotypic abnormalities are lacking. In these cases a multi-diagnostic approach is recommended. Purpose: The aim of this study was to investigate the role of flow cytometry (FC) in the diagnosis of MDS when CM and CG are indeter- minate. Materials and Methods: We collected bone marrow samples of 249 patients with “cytopenia of unknown origin”, who were routinely an- alyzed by CM and FC combined with CG and molecular biology (MB), the latter only if indicated. Results: In this population 61 patients were diagnosed with MDS, 75 patients were diagnosed with (non) clonal diseases and in 12 pa- tients CM and FC showed normal bone marrow (BM). Eight of the patients with normal BM could be diagnosed as an idiopatic cytope- nia of undeteminate significance (ICUS); others were diagnosed as cytopenia caused by medication (N=3) or chronic renal failure (N=1). The remaining patients (N=101) showed <10% dysplasia in 1 or more cell lineages by CM (n=60), or CM was reported inconclusive, e.g. hypocellular (N=36), or CM was not evaluable because of a dry tap (N=5). CG analysis identified 1 patient with a monosomy 7. Rou- tine MB gave no additional information when CM was inconclusive. In the 99/100 CM-inconclusive patients remaining, FC in BM iden- tified 9 patients as MDS, 11 patients with dysmyelopoiesis and 79 patients without dysmyelopoiesis. From the 79 CM-inconclusive/FC- negative patients 3 developed MDS (4%), compared to 3 out of 9 CM-inconclusive/FC-positive patients (33%). The negative predictive value of FC within the CM-indeterminate subpopulation was 96% compared to 88% in the total population at current time of analysis. Conclusions: We hereby demonstrate that FC is of important addi- tional value in distinction between clonal and non-clonal causes of cytopenia when CM and CG are indeterminate. The precise role of FC in the diagnosis of ICUS needs to be determined during longtime follow-up. P-079 Complex chromosomal abnormalities in MDS B. Ganguly 1 , S. Mandal 1 , M. Ghosh 2 , T. Dolai 2 , M. Bhattacharyya 2 , D. Banerjee 3 , D. Banerjee 3 , S. Chandra 3 . 1 Genetics, Genetics Center, Mumbai, India; 2 Hematology, NRS Medical College, Kolkata, India; 3 Hematology, Clinical Hematology Services, Kolkata, India Background: Non-random chromosome abnormalities are well un- derstood in hematological malignancies. Characterization of chromo- somal aberrations is important in classification and prognostication of this acquired disease. MDS is a heterogeneous neoplasia where chromosome study helps in confirmation of the disease and intro- duction of an accurate treatment module. Introduction: Normal chromosomal complements are often re- ported in myelodysplastic syndrome (MDS) by G-banding whereas fluorescence in situ hybridization could report precisely on common aberrations such as del(5q), -7, del(7q), +8, etc. depending on the probe combination used for the purpose. Conventional cytogenetic study of MDS is able to study all recognizable abnormalities present in acquired or constitutional forms. Purpose: Cytogenetic study was performed to understand the chro- mosomal complements towards confirmation of diagnosis of MDS. Materials and Methods: We report 89 cases of provisionally diag- nosed MDS during the year 2012 for chromosomal aberrations by employing G-banding technique on metaphases obtained from un- stimulated 24h culture of bone marrow samples. Results: Metaphases could not be traced in four (5%) cases. A total of 32% cases were detected with a single clonal aberrations, including del(7q) (1%), monosomy 7 (5%), trisomy 8 (7%), trisomy 21 (5%), del(20q) (5%) and loss of Y (5%) as frequently observed aberrations. Complex and multiple aberrations were recorded in 5% cases, including 48,XY,+4,+8, 46,XX,inv(9),del(5q),11(p13), 47,XY,del(5q),del(7q),+8,t(3p;11q23) and 46,XX,del(5q),-11,+mar, der(12)t(11q;12p). Chromosomal complements were consistent in follow up study of complex cases after a year. Therefore, a total of 37% cases were appeared with acquired aberrations. In addition, constitutive aberrations were present in 2% cases. Tetraploidy and breaks were noticed in over 50% cases. Conclusions: Additional and complex abnormalities are important for prognostication and assumed to interfere with treatment out- come. P-080 The morphology, immunocytochemistry and genetics of PC-MDS cell line, established from a bone marrow of the patient with therapy-related myelodysplastic syndrome V. Jurisic 1 , G. Bogdanovic 2 , S. Pavlovic 3 . 1 Faculty of Medicine, Faculty of Medical Sciences, Kragujevac, Serbia; 2 Experimental laboratory, Institute of Oncology, Novi Sad, Serbia; 3 Laboratory for Hematology, Institute of Molecular Genetics and Genetic Engineering University of Belgrade, Belgrade, Serbia