Cytogenetic Features and Prognosis of 943 South American Patients with De Novo Myelodysplastic Syndromes: A Multicenter Study

BELLI C; FEITOSA PINHEIRO R; SILVA M; MAGALHAES M; GONZALEZ J; IASTREBNNER M; PRATES V; BESTACH Y; CORDEIRO J; SILVA TANISAWA R; BENGIO R; LANG C; NUCIFORA E; LARRIPA I; VELLOSO E

San Francisco

Congreso; 56th ASH Annual Meeting and Exposition; 2014

American Society of Hematology

Recently, the IPSS-R has proposed five cytogenetic groups of risk (CGR) based on Schanz et al, 2011, proposal. Nevertheless, nearly 70% of patients belong to lower CGR. Our aim was to characterize the cytogenetic profile of South American (SA) MDS population trying to find differences among Argentine (A) and Brazil (B), both with diverse ethnicity, to evaluate CGR, and to define the impact of more frequent aberrations and of monosomal karyotype (MK) in our population. This is a multicenter retrospective study of 943 SA (634 from A and 309 from B) de novo MDS patients (pts) evaluated from 1981 to 2014. Pts were classified following FAB and WHO criteria. The median age was 69 (15-99) years old with a male/female ratio of (533/410) 1.3. During the follow-up, censored up to receiving a disease modifying therapy (median: 21 months), 159 (17%) evolve to AML and 351 (37%) died. Regarding 130 pts (14%) who received hypomethylating therapy (HMT), 46 (35%) evolved to AML, and 61 (47%) died. Although A population was larger than B series, no differences were observed concerning to: CGR distribution according to the IPSS (p=0.565) and to the IPSS-R (p=0.343), percentage of abnormal karyotypes (42%-A vs 40%-B; p=0.499), and presence of deletions and/or monosomies (77%-A vs 80%-B, p=0.700). B showed a higher proportion of karyotypes involving, at least, one chromosome Y, 5, 7, 8 and/or 20 (83% vs 73%-A, p=0.039), mostly due to a higher proportion of 5q- (39% vs 22%-A, p