P126 Treatment of progression of myeloproliferative neoplasm (MPN) to MDS/AML by azacytidine (AZA): a report on 44 patients (pts)

Abstract

Aberrant expression of the adhesion molecule CD44 correlates with poor prognosis in various neoplasms. To evaluate the prognostic impact of CD44 in myelodysplastic syndromes (MDS) serum levels of soluble CD44 (sCD44) were measured in 130 MDS patients using an enzymelinked immunosorbent assay (ELISA). sCD44 levels were significantly elevated in MDS patients compared to healthy donors (p< 0.05), and were found to correlate with distinct FAB subtypes. The highest levels of sCD44 were found in patients with CMML and in patients with MDS transformed into acute myeloid leukemia (AML). In univariate analysis elevated levels of sCD44 s were significantly correlated with shorter overall survival in MDS-patients (9 versus 37 months; p< 000). In multivariate analysis sCD44 s displayed prognostic significance for survival independent from the International Prognosis Scoring System (IPSS). To test for refined prognostication, each IPSS risk group was split into two separate categories based on sCD44 s levels. Using this approach, MDS patients with a shorter survival were identified both in the IPSS low-risk (p = 0.014) and in the IPSS Int-1 group (p = 0.031). The CD44 s-adjusted IPSS defines a cohort of MDS patients with unfavorable prognosis within the low and intermediate-1 IPSS groups, which might be helpful in risk stratification and in therapeutic algorithms.