Overall survival of myelodysplastic syndrome patients after azacitidine discontinuation and applicability of the North American MDS Consortium scoring system in clinical practice.

BACKGROUND: Azacitidine (AZA) is the standard treatment for myelodysplastic syndromes (MDS); however, many patients prematurely stop therapy and have a dismal outcome. METHODS: The authors analyzed outcomes after AZA treatment for 402 MDS patients consecutively enrolled in the Italian MDS Registry of the Fondazione Italiana Sindromi Mielodisplastiche, and they evaluated the North American MDS Consortium scoring system in a clinical practice setting. RESULTS: At treatment discontinuation, 20.3% of the patients were still responding to AZA, 35.4% of the cases had primary resistance, and 44.3% developed adaptive resistance. Overall survival (OS) was better for patients who discontinued treatment while in response because of planned allogeneic hematopoietic stem cell transplantation (HSCT; median OS, not reached) in comparison with patients with primary resistance (median OS, 4 months) or adaptive resistance (median OS, 5 months) or patients responsive but noncompliant/intolerant to AZA (median OS, 4 months; P = .004). After AZA discontinuation, 309 patients (77%) received best supportive care (BSC), 60 (15%) received active treatments, and 33 (8%) received HSCT. HSCT was associated with a significant survival advantage, regardless of the response to AZA. The North American MDS Consortium scoring system was evaluable in 278 of the 402 cases: patients at high risk had worse OS than patients at low risk (3 and 7 months, respectively; P < .001). The score was predictive of survival both in patients receiving BSC (median OS, 2 months for high-risk patients vs 5 months for low-risk patients) and in patients being actively treated (median OS, 8 months for high-risk patients vs 16 months for low-risk patients; P < .001), including transplant patients. CONCLUSIONS: Real-life data confirm that this prognostic scoring system for MDS patients failing a hypomethylating agent seems to be a useful tool for optimal prognostic stratification and for choosing a second-line treatment after AZA discontinuation.

Prognostic relevance of cytometric quantitative assessment in patients with myelodysplastic syndromes.

OBJECTIVES: Morphology and cytogenetics are currently used to define prognosis in myelodysplastic syndromes (MDS). However, these parameters have some limits. Flow cytometry has been recently included in the diagnostic panel for MDS, and its prognostic significance is under evaluation. METHODS: Marrow aspirates from 424 MDS patients were analyzed by flow cytometry to evaluate the impact of bone marrow cell immunophenotype on overall survival (OS) and leukemia-free survival (LFS). The immature compartment of myeloblasts was analyzed by the quantitative expression of CD34 (<3% vs. ≥3%), CD117, and CD11b(-) /CD66b(-) (<5% vs. ≥5%); myeloid maturation was analyzed by the expression of CD11b(+) /CD66b(++) (<15% vs. ≥15%) and CD11b(+) /CD66b(+) (<25% vs. ≥25%). RESULTS: In univariate analysis, the expression of immaturity markers (CD34(+) , CD117(+) , and CD11b(-) /CD66b(-) ) was associated with shorter LFS and OS (P < 0.0001); higher expression of differentiation markers (CD11b(+) /CD66b(++) and CD11b(+) /CD66b(+) ) was associated with longer LFS (P < 0.0001 and P = 0.0002, respectively) and OS (P < 0.0001). In multivariate analysis, expression of CD34(+) (P = 0.007), CD117(+) (P = 0.013), and CD11b(+) /CD66b(++) (P = 0.023) retained independent prognostic value for OS, while only the expression of CD34(+) was a prognostic factor for LFS (P = 0.0003). Two different risk groups were defined according to the presence of 0-1 or ≥2 of these factors with significant different LFS and OS (P < 0.0001). This score showed prognostic value in predicting survival even in subanalysis according to IPSS and WHO subgroups. CONCLUSIONS: Flow cytometric analysis in MDS may provide meaningful prognostic information. Blast percentage expressed as CD117(+) or CD34(+) cells and the quantitative assessment of myeloid maturation showed prognostic value for survival.