12th Congress of the European Hematology ... - Haematologica

sion. In addition, confocal analysis showed that ARHGAP21 is preferentially
localized in the cytoplasm of the MNCs, but after DAC treatment
this protein translocates into the nucleus. Conclusions. ARHGAP21
is overexpressed in AML and ALL cells and our data show a tendency
to higher expression of ARHGAP21 in high-risk MDS cells. The downregulation
of ARHGAP21 in MNCs co-cultured or not with stroma cells
by DAC treatment, in parallel with its translocation cytoplasm-nucleus,
suggest that ARHGAP21 may be involved in the abnormal phenotype
of MDS cells and might be a target of DAC treatment, aiming this gene
an important candidate for anti-tumor therapy. Supported by: FAPESP
and CNPq
0633
SEQUENTIAL CYTOGENETIC STUDIES IN 79 PATIENTS WITH MYELODYSPLASTIC
SYNDROME
M. Pelizzari, 1 M. Drera, 1 D. Bellotti, 2 D. Marocolo, 2 S. Barlati, 2
F. Facchetti, 2 G. Rossi1 1 Spedali Civili, BRESCIA; 2 Università degli Studi, BRESCIA, Italy
Background. While karyotype and cytopenias are useful in desease
monitoring in myelodysplastic syndrome (MDS), little data exist on the
prognostic impact of cytogenetic changes on outcome and survival. Aims.
To analyse the usefulness of adding karyotypic studies to the marrow
cytological follow-up during the course of myelodysplastic syndromes
(MDS). Methods. In 79 MDS pts aged 68 ys (range 15-91), F/M 31/48, a
karyotypic study was performed whenever pts underwent marrow morphological
reevaluation. Their median follow-up was 13 months (range
0-97). All cases were treated with supportive measures ± growth factors,
corticosteroids. Low-dose hydroxyurea was used in 4 pts with CMML.
Pts treated with aggressive chemotherapy were excluded. MDS were
defined according to FAB classification and karyotypes were classified
according to IPSS risk classes.
Figure 1.
Results. A total of 119 combined morphological/cytogenetic analyses
were performed. There were 46 RA, 4 RARS, 38 RAEB, 10 RAEB-T, 10
CMML and 11 MDS not specified. Distribution among IPSS karyotype
groups was: 66 good, 26 intermediate and 27 poor. At baseline no significant
correlation was found between FAB morphology and IPSS cytogenetic
risk class. FAB morphology remained stable in 49 cases (41%); it
regressed to a lower risk FAB class in 11 cases (better morphology: 9%).
Morphological evolution occurred in 59 cases (50%), respectively to a
higher risk MDS FAB class in 19 (worse MDS morphology: 16%), or to
acute leukaemia in 40 (leukaemic evolution: 34%). IPSS karyotype risk
12 th Congress of the European Hematology Association
class was stable in 84 cases (70%). It regressed to a lower IPSS risk in 14
(better karyotype: 12%) and progressed to a higher IPSS risk in 21 (worse
karyotype: 18%). No significant correlations were found between the
morphological and cytogenetic variations. The incidence of both
favourable (IPSS good) or unfavourable karyotype (IPSS
intermediate+poor) progressively decrease with increasing marrow
blasts percentage: respectively, for RA, RARS, CMML, NAS: 59%
favourable vs. 58,5% unfavourable; for RAEB: 32% vs 34% and for
RAEB-T: 9% vs 7,5%. Morphological changes during follow-up had a
significant impact on median survival, which was 12 months (range: 0-
68) in pts both with better and stable morphology, 5 months (0.5-97) in
pts with worse MDS and 3 months in pts with leukaemic evolution
(p