Question | Answer |
Myelodysplastic Syndromes Overview ? | * A group of clonal stem cell disorders characterized by maturation defects
---Associated with ineffective hematopoiesis
---High risk of transformation to AML
--- can see anemias, infections, and bleeding---- blast count below 20% |
MDS Testing ? | * CBC – pancytopenia
----Peripheral blood – dysplasia in one or all cell lines
----Bone marrow aspiration & biopsy
<20% blasts---- Flow cytometry – confirms absence of AML
----Cytogenetics ...... * nothing in blood can make Dx , need BM biopsy |
MDS BM Morphology ? | * Erythroid dysplasia - see Ringed sideroblasts..... * Neutrophil dysplasia - Decreased secondary granules (hypogranular)and Pseudo Pelger-Huet cells .... * Megakaryocyte dysplasia - Myeloblasts MUST be less than 20%
and NO Auer rods |
MDS PB Morphology ? | * Pseudo-Pelger-Huet cells
---Hypogranular neutrophils
---Giant platelets
---Macrocytes
---Poikilocytes (schistocytes and spherocytes are NOT seen)
---Relative or absolute monocytosis
---Myeloblasts MUST be <10% of the leukocytes |
MDS WHO Classification ? | * Refractory cytopenia with unilineage dysplasia (RCUD)--
Refractory anemia, refractory neutropenia, refractory thrombocytopenia
<5% of cases
.....*Refractory anemia with Ringed Sideroblasts (RARS)
--- <5% of cases |
continued.... | * Refractory cytopenia with multilineage dysplasia (RCMD)
-- 70% of cases – in more than 1 cell line
.....* Refractory anemia with excess blasts (RAEB)
-- 25% of cases – morethan 3, less than 20 |
continued... | * MDS with isolated del(5q)
--5% of cases
....*MDS, unclassified
-- <5% of cases |
Refractory Cytopenia with Unilineage Dysplasia (RCUD) ? | * <5% blasts in the BM.... * Dysplasia in >10% of cells in one lineage |
Refractory Anemia with Ringed Sideroblasts (RARS) ? | * >15% ringed sideroblasts in the bone marrow
---- 10 or more iron-laden mitochondria occupying more than 1/3 of nuclear rim |
Refractory Cytopenia with Multilineage Dysplasia (RCMD) ? | * Severe dysplasia in two or more cell lines.... * RCMD-RS --> increased ringed sideroblasts in addition to above |
Refractory Anemia with Excess Blasts (RAEB) ? | * 5-9% = RAEB-I ...... * 10-19% = RAEB-II shorter survival and increased risk of developing AML ...... * Dysplasia present
..... *NO Auer rods |
MDS with Isolated del(5q) ? | * 5q- Syndrome, and best prognosis .... * Severe anemia, normal platelet count ..... * RBC transfusions may be necessary
.....*BM with micromegakaryocytes (mono or bilobed nuclei), <5% myeloblasts |
Myeloproliferative Disorders Overview ? | * Group of disorders with increased proliferative drive in BM.... * BM fibrosis and PB cytopenias.... * BM doesn't make enough RBCs bc of fibrosus.... * also see high numbers of one type of cells |
MPD Testing ? | * CBC – increase in one or more cell lines
.... * Peripheral blood – maturation without excess blasts, should not be there ..... * Bone marrow aspiration & biopsy
- <20% blasts
-- Maturation of involved cell lines |
continued.... | * Erythropoietin levels - markedly decreased in PV....
* Uric acid – increased due to cell turn-over |
Chronic Myeloid Leukemia (CML) ? | * synthesis of active BCR-ABL tyrosine kinase --> t(9;22)the Philadelphia Chromosome .... * Sea-blue histiocytes .... * all levels of granulocytic maturation (<5% blasts); nucleated RBCs; increased Bo
& Eo; few promyelocytes; giant platelets |
Chronic Myeloid Leukemia (CML) clinically ? | * splenomegaly - giant spleens ... * indigestion and fatigue ... * high WBC count with low blast count .... * can get ALL or AML |
Polycythemia Rubra Vera (PV) ? | * mutations in tyrosine kinase JAK2 --> decreased need for erythropoietin in RBC production .... * Increased total blood volume viscosity with abnormal platelet function --> bleeding and thrombosis .... * Hemoglobin = 14-28 gm/dl *Hematocrit = >60% |
Essential Thrombocythemia (ET) ? | * activating point mutations in JAK2 or MPL --> decreased need for thrombopoietin.... * megakaryocytes markedly increased ... * Giant platelets .... * Erythromelalgia – throbbing & burning of hands and feet .... * super high platelets and Bleed |
Primary Myelofibrosis ? | * activating JAK2 or MPL mutations.... * see BM fibrosus, so causes a dry tap on biopsy .... * see Osteosclerosis... * erythroblastosis; tear drop RBCs; giant platelets; increased basophils .... * die in 3 - 4 years |