Term
| what are myelodysplastic syndromes? |
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Definition
| a heterogenous collection of clonal hematopoietic stem cell malignant disorders marked by ineffective hematopoiesis leading to anemia, thrombocytopenia, and neutropenia. 33% go on to develop acute leukemia (generally AML), and they proceed marrow failure. these used to be called *refractory anemias. |
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Term
| what is the most common hematologic malignancy in the elderly? |
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Definition
| myelodysplastic syndrome - median age 60-75 *not rare - tired bone marrow, due radiotherapy etc |
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Term
| what is primary myelodysplasia? |
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Definition
| idiopatic, non-comples cytogenetics, low IPSS, and responds better to therapy |
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Term
| what is secondary myelodysplasia? |
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Definition
| usually due to chemo, has comples cytogenetics, high IPSS, and refractory to therapy |
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Term
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Definition
| peripherial blood monocytosis, presents with <5% blasts in peripheral blood and up to 20% blasts in the bone marrow |
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Term
| what are auer rods seen in? |
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Definition
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Term
| what is refractory anemia? |
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Definition
| erythroid dysplasia, <5% blasts, <15% ringed sideroblasts, no auer rods |
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Term
| what is refractory anemia w/ringed sideroblasts? |
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Definition
| <5% blasts, <15% ringed sideroblasts, no auer rods |
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Term
| what is refractory cytopenia with multilineage displasia? |
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Definition
| dysplasia in >10% of cells in 2+ cell lines |
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Term
| what is refractory cytopenia with multilineage displasia w/ringed sideroblasts? |
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Definition
| dysplasia in >10% of cells in 2+ cell lines with >15% ringed sideroblasts |
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Term
| what is refractory anemia with excess blasts types 1 and 2? |
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Definition
RAEB 1: 5-9% blasts, no auer rods
RAEB 2: 10-19% blasts, +/- auer rods
(both can be uni or multilineage dysplasa) |
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Term
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Definition
| a unilineage myelodysplasia, <5% blasts and no auer rods. lenalidamide specifically approved by FDA to treat this |
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Term
| how are myelodysplasic syndromes diagnosed? |
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Definition
| blood count, if low, could be MDS due to anemia, neutropenia, thrombocytopenia, or any combo - so do bone marrow bx and look for dyplastic features. cytogenetics should also be assessed. |
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Term
| how doe myelodysplastic syndromes present clinically? |
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Definition
| macrocytic anemia, low retic count (BM not working), normal to high EPO (high because body is trying to stimulate more RBCs). B12/folate deficiency needs to be ruled out esp if macrocytic |
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Term
| how do myelodysplastic syndromes appear in a bone marrow bx? |
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Definition
| megaloblastic erythroid cells, ringed sideroblasts, micromegakaryocytes, and large/giant dysfunctional platelets |
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Term
| how are myelodysplastic syndromes treated? |
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Definition
| there is no standard of care, supportive care: transfusions, growth factors (EPO, G-CSF, GM-CSF, IL-11), chemotherapy, (azcitidine, lenalidomide, amfostine) |
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Term
| how does azacitidine work? |
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Definition
| azacitidine treats MDS by DNA hypomethylation, which restores normal function of differentiation/proliferation. it is directly cytotoxic. can double 2 yr survival. |
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Term
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Definition
| a thalidomide analogue that has no sedation or neuropathy associated with it. this improved RA in 64% of pts in an 8 wk study and will also work for 5q- |
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Term
| what is a caution for giving pts repeated transfusions? |
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Definition
| the body has no way of getting rid of iron, so they can get iron overload |
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Term
| what drug can help with sideroblast forms of RA? |
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Definition
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Term
| what MDS has the lowest likelihood of leukemia? what MDS has the highest likelihood of leukemia? |
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Definition
| lowest: RA or RARS - b/c lowest blast level. highest: RAEB II |
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