MDS Flashcards
Myelodysplastic Syndrome (MDS)
Neoplastic disorder characterized by one or more lineage cytopenias
30% of patients progress to AML
Present with macrocytic normochromic anemia and dyserythropoiesis (myeloid and megakaryocytic)
Mostly in adults, coupled with Down’s syndrome in kids
MDS RBC Findings
Macrocytic anemia with normal folate and B12 levels
Dimorphic RBC population
Pappenheimer bodies, basophilic stipping, sideroblasts, erythroid hyperplasia, megaloblastoid changes, karyorrhexis
MDS WBC Findings
Pseudo-Pelger Huet anomaly
Hypogranulation, neutropenia, monocytosis, irregular/hypersegmentation
Occasional ring nuclei
MDS Megakaryocytic Findings
Thrombocytosis or thrombocytopenia
Giant platelets, hypogranulation, micro-megakaryocytes
Mononuclear or multiple seperated nuclei in megakaryocytes
Refractory Anemia (RA)
<5% blasts
<15% ringed sideroblasts
Dyserythropoiesis in the bone marrow
Megaloblastoid changes
RA with Ringed Sideroblasts (RARS)
> 15% ringed sideroblasts
<1% blasts
Dimorphic RBCs, possible Pappenhaimer bodies
RA with Excess Blasts (RAEB)
5 to 20% blasts
Dimorphic RBCs, possible Pappenheimer bodies
RA with Excess Blasts in Transition (RAEB-IT)
> 5% blasts in the peripheral blood
21 to 30% blasts in the bone marrow
Dimorphic RBCs, possible Pappenheimer Bodies
FAB vs WHO Classifications of Leukemia
Acute leukemia
WHO >20% blasts in bone marrow
FAB >30% blasts in bone marrow
5q Syndrome
Loss of the long arm of chromosome 5
Macrocytic anemia and mono-lobed megakaryocytes
Chronic Myelomonocytic Leukemia (CMML)
Hetergeneous disorder characterized by absolute monocytosis and <20% blasts in the bone marrow
CMML 1
Absolute monocytosis
<5% blasts in the peripheral blood
<10% blasts in the bone marrow
CMML 2
Absolute monocytosis
5 to 19% blasts in the peripheral blood
10 to 19% blasts in the bone marrow
