The myelodysplastic syndromes (MDS)

Aquired Clonal disease of BM . comprise a heterogeneous group of malignant stem cell disorders characterized by :

1-dysplastic 2-Ineffective blood cell production . ………………….(ie, apoptotic death) .

3- Variable risk of transformation to …………………………..acute leukemia ( AML ).

These disorders may occur de novo or arise years after exposure to potentially mutagenic chemotherapy and Iradiation.

MDS SubtypesMDS Subtypes

-Refractory anemia (RA)

-RA with Ring Sideroblasts ( RARS)

-RA with excess blasts (RAEB)

-RAEB in Transformation (REABt)

-Chronic Myelomonocytic leukemia

Risk Factors of MDSRisk Factors of MDS

-Down’s syndrome

-Previous Chemotherapy

-Chemical Exposure ( eg Benzene )

-Iradiation

CLINICAL PRESENTATION of MDS :

peripheral cytopenias (ie, anemia,

neutropenia, and thrombocytopenia) Many patients are asymptomatic, with a diagnosis established upon routine laboratory screening.

fatigue, weakness, exercise intolerance angina, dizziness

Less commonly, infection, easy bruising

or bleeding .

Clinical features of MDS

-Asymtomatic with Macrocytic anemia

-Symptomatic anemia

-Infections. (Neutropenia)

-Hemorrhagic manifestation

-General symptom. (weight loss , sweats…)

FAB Classification of MDSFAB Classification of MDS

MDS FAB Subtype Blood Marrow blasts %

RA Mono<1% Blast 1% <5% RARS Mono<1% Blast<1% <5%

RAEB Blast<5% 5-20%

RAEBt Blast Variable 20-30%

Cmml Mono>5% Blast,5% <5%