Diagnosis, Classification peripheral blast count do not have a worse prognosis. This findings support the reclassification of patients with RAEB based on the peripheral and medullary blast counts in the WHO system. The WHO-classification should be used for risk stratification and clinical decision making in RAEBpatients, because high-risk patients, who should be treated with chemotherapy or stem cell transplantation can be detected.
~ R A AND RARS WITH THROMBOCYTOSIS: MIXED MYELODYSPLASTIC/ MYELOPROLIFERATIVE DISORDER? S. Knipp 1 *, C. Strupp 1, A. Bernhardt 1, E. Misgeld1, B. Hildebrandt2, R. Haas 1, N. Gattermann 1, U. Germing1.
1Haematology University Dusseldorf 2Human Genetics University Dusseldorf Germany *E-maih [email protected]
f.de Myelodysplastic syndromes comprise a heterogeneous group of multipotent stem cell disorders characterised by cytopenia and qualitative defects of erythroid, myeloid and megakaryocytic maturation. In myeloproliferative syndromes however, maturation and proliferation of bone marrow cells is effective and there is an overproduction of end cells. There are MDS patients, who have characteristics of myeloproliferative disorders like organomegaly or high cell counts in peripheral blood. Clinical overlap syndromes can occur within myelodysplastic disorders, especially in CMML. We turned to the Dusseldorf MDS registry in order to identify RA and RARS patients with thrombocytosis. Thrombocytosis could be seen in about 11% of all RA and RARS patients, more frequent in patients with 5 % anomaly (28%). 27 patients out of 179 patients (15%) with a normal karyotype had a platelet count at diagnosis of more than 400,000/ml. The majority of these patients had normal white blood cells counts and only mild anemia. Thrombocytosis in MDS was most frequent in the RARS group (17%), ranging from 400,000/ml, to 1,500,000/ml, sometimes accompanied by organomegaly. Cellularity of the megakaryocytosis regularly was increased like in essential thrombocytosis. Degree of dysplasia of megakaryopoisis was not different between patients with low or normal and high platelets count. Patients with RA and RARS with high platelet counts may represent another type of mixed myelodysplastic/myeloproliferative disorders.
PROSPECTIVE VALIDATION OF THE WHO CLASSIFICATION OF PRIMARY MYELODYSPLASTIC SYNDROMES
Kuendgen 1 *, S. Knipp 1, M . A i v a d o 1 , M . L a r a 1 , S. Isa 1, A. Giagounides2, C. AUl2, R. Haas 1, N. Gattermann 1, U. Germing1. 1Department of Hematology, Oncology, A.
and Clinical Immunology, Heinrich-Heine-University, Duesseldo~ 2St.-Johannisho~pital, Duisburg, Germany *E-maih [email protected]
f.de In order to validate the WHO classification for myelodysplastic syndromes (MDS) in a prospective manner, we started to classify all MDS patients diagnosed at our institution since July 1999 according to the WHO and FAB proposals. All patients were followed for survival and AML evolution through December 3 lth 2004. There were 372 RA (median survival [ms] 50 months), 127 RARS (ms 40 months), 171 RAEB (ms 18 months). According to WHO there were 57 RA, 281 RCMD, 21 RARS, 104 RSCMD, 36 5 ~ , 92 RAEB I and 77 RAEB II. Median survival of RA was not reached (n.r.), of RCMD was 44 months, of RARS was n.r., of RSCMD was 26 months, of 5 ~ was n.r., of RAEB I was 25 months and of RAEB II was 10 months (p < 0.00005). There was a significant difference between RAEB I and RAEB II (p 0.0004). There was no difference between RA, RARS and 5 ~ on the one hand and RCMD and RSCMD on the other hand. Cumulative AML evolution 2 years after diagnosis was 0% in RA and RARS, 8% in 5 ~ and RSCMD, 11% in RCMD, 14% in RAEB I and 55% in RAEB II. According to our data, the WHO classification provides valuable prognostic information concerning survival and AML evolution. Further long-term studies including cytogenetics are warranted.
P - 3 1 3q CYTOGENETIC ABERRATIONS IN A SERIES OF 223 MYELODYSPLASTIC SYNDROME (MDS)/CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) PATIENTS FROM A SINGLE INSTITUTION E Cobo 1 *, I. Madrigal2, M. Rozman 3, D. Costa2, A. Carrio 2, E. Arellano 1, S. Valera 2, J.L. Aguilar3, E. Montserrat 1, E. Campo 3, B. Nomdedeu 1.
1Department of Hematology, 2Department of Genetics, 3Hematopathology Unit, Department of Pathology, Ho~Tital Clinic, IDIBAPS, Barcelona, Spain *E-maih [email protected]
3q rearrangements are associated with a poor outcome in MDS/CMML, but they are not included in the International Prognosis Scoring System (IPSS) bad prognosis cytogenetics group. Among 223 MDS/CMML patients seen at our institution from 1997 to 2002, three patients with 3q abnormalities were identified (1.3% of the series; median