Unit 3: Myelodysplastic Disorders Flashcards
Three Groups of Clonal Myeloproliferative Disorders:
- AMLs
- Chronic Myeloproliferative Disorders (CMPDs)
- Myelodysplastic Syndromes (MDSs)
MDSs are typically seen in what population?
in older (>50 years) pts., especially males
What are the 3 types of diseases of MDSs?
- Primary (de novo)
- Treatment-related (2-5 yrs. post-chemo.)
- Very rarely, inherited (FYI: There is a pedi. MDS in this category.
Myelodysplastic Syndromes (MDSs):
Often called preleukemias: they range from a mild anemia to a malignant disease that rapidly terminates in _____!
AML
Difficult disease to recognize for what it is. Incidence of MDS cases wasn’t even tracked until _____.
2001
MDS general characteristics:
Apparently the stem cell DNA sequences acquire permanent mutations, particularly involving chromosomes ___ and ____.
- Most cases involve a defect at the Myeloid Stem Cell
- Each mutated stem cell produces a unique clone w/ a specific cellular
defect….leading to multiple expressions!
5 and 7
MDS:
Apoptosis is _________ early in disease, but ___________ later when converting to leukemia
increased
decreased
MDS general characteristics:
Result is ineffective clonal _____________ ( = too few cells) plus morphologic
__________ (= “ugly” cells)!
hematopoiesis
dysplasia
- MDS cells apparently produce cytokines that kill off N. cells, so . .
- Progressive p.b. __________ occur, with dyspoiesis (abnormal development)
in 1 or more cell lines
cytopenias
All MDSs have…
______________– occurs first; see oval macrocytes (1 st thought? Megaloblastic anemia), megaloblastoid bone marrow with bizarre nRBCs, some ringed sideroblasts, & dimorphic RBCs
Dyserythropoiesis
Most MDSs have…
________________ - persistent basophilic cytoplasm, abnormal granules & nuclei, uneven cytoplasmic staining, & occ’l. Auer rods (even before it’s officially a leukemia).
Dysmyelopoiesis
Some MDSs have…
____________ - giant plts., bizarre & mononuclear megakaryocytes, & abnormal granules
Dysmegakaryopoiesis
What is a major feature of MDS?
what is NOT seen until disease transforms into leukemia?
*cytopenias
hyperproliferation
MDS can stay stable for years with only ________ evident.
dysplasia
Pts may be _________ to treatment once therapy is finally needed.
refractory
Do cells have normal function with MDS?
no, abnormal.
-these conditions have variable severity
MDS clinical symptoms
- Fatigue
- Fever
- Bleeding
-However, many pts. are asymptomatic in early stages.
General P.B. Findings in MDSs
- Progressive cytopenia
- Megaloblastoid dyserythropoiesis in bone marrow
- Neutropenia
- Giant plts., circulating micromegakaryocytes/-blasts! (Similar to AMegL)
Megaloblastoid dyserythropoiesis in bone marrow, which manifests in p.b. as…
Hgb <10 g/dL
Variable degrees of : aniso, poik, Howell-Jolly bodies, basophilic stippling, & bizarre nRBCs
MDS P.B findings with neutropenia?
↑ metas & myelos, with morphologic abnormalities; may be Auer rods, may exhibit pseudo-Pelger-Huet
General Bone Marrow Findings in MDSs?
- Bone marrow sample always required for diagnosis.
- Bone marrow generally always hypercellular due to
erythroid hyperplasia. - Ringed sideroblasts common.
General Bone Marrow Findings in MDSs:
Hallmark finding is…
***megaloblastoid dyserythropoiesis!!!
FAB Classification Scheme for MDSs relies on _____________ alone, so has limited prognostic utility.
morphology
-Each of these is pretty much a basic Refractory Anemia (RA), but with increasingly more severe problems overlaid on top of it
In order of increasing severity (some pts. will actually progress through each until it finally becomes an AML!):
- Refractory Anemia (RA)
- Refractory Anemia w/ringed sideroblasts (RARS)
- Refractory Anemia w/excess blasts (RAEB)
- Chronic Myelomonocytic Leukemia (CMML)
- Refractory Anemia w/Excess Blasts in Transformation (RAEBIT, or RAEB-t)
FAB subgroups of MDS (general criteria)
*% blasts in bone marrow
*% blasts in p.b.
*± ringed sideroblasts
*% of monocytes
*extent of cytopenias
*degree of dyspoiesis (bizarre forms)
Four most common WHO subgroups of MDS
- Refractory Anemia (RA) - Refractory Cytopenia with
Unilineage Dysplasia (RC) - Refractory Anemia w/ringed sideroblasts (RARS)
- Refractory Anemia w/excess blasts (RAEB)
- Condition called MDS Unclassified (MDS-U).
Refractory Anemia (RA) - Refractory Cytopenia with
Unilineage Dysplasia (RC):
stable deletion syndrome (found in elderly women, has good prognosis.)
5q- Syndrome
Refractory Anemia (RA) - Refractory Cytopenia with
Unilineage Dysplasia (RC):
(like RARS, but affects > 1 cell line.)
Refractory PanCytopenia with Multi-lineage Dysplasia,
or RCMD
Chronic Myelomonocytic Leukemia (CMML) – moved to what classification?
myeloproliferative
disorders as MPN, Unclassified
Refractory Anemia w/Excess Blasts in Transformation – moved to what classification?
AML
Primary finding with Refractory Cytopenia with
Unilineage Dysplasia?
anemia with oval macrocytes (but not a simple ovalocytosis – this is a true
megaloblastoid picture)
Refractory Cytopenia with
Unilineage Dysplasia:
-bone marrow blasts ___%.
-Rare ringed sideroblasts (_____%) & siderocytes.
<5
<15
Refractory Cytopenia with
Unilineage Dysplasia:
- % p.b. blasts _____%.
- Normal B 12 & folate levels.
<1
Is Dysmyelopoiesis or dysmegakaryopoiesis present with Refractory Cytopenia with
Unilineage Dysplasia?
rarely present
Just like RA, but with more ringed sideroblasts (>15% of nucleated cells in bone marrow):
* < 5% blasts in bone marrow
* Usually exhibits dimorphic RBC population
Refractory Anemia with Ringed Sideroblasts (RARS)
RA, + cytopenia in 2 cell lines now, & even more blasts!
Refractory Anemia with Excess Blasts (RAEB)
- Advent of prominent dysgranulopoiesis, plus some dyserythropoiesis (& rarely, some dysmegakaryopoiesis.)
- May have pseudo-Pelger-Huet.
Refractory Anemia with Excess Blasts (RAEB)
Refractory Anemia with Excess Blasts (RAEB):
- ___% blasts in p.b.
- Bone marrow blasts now up to _____%!
less than or equal to 5
5 - 20
Refractory Anemia with Excess Blasts (RAEB) symptoms?
anemia, fever, bleeding, and infection
RA, but with mostly monos in bone marrow
(>20%)
Chronic Myelomonocytic Leukemia (CMML)
-This is NOT the M4 AMML!
Chronic Myelomonocytic Leukemia (CMML) is unusual MDS bc. it’s only one to have leukocytosis instead of ?
leukopenia
WHO has moved Chronic Myelomonocytic Leukemia (CMML) into what category?
Myeloproliferative Disorders category
Chronic Myelomonocytic Leukemia (CMML):
Absolute p.b. _____________ with morphological abnormalities always present
monocytosis
Chronic Myelomonocytic Leukemia (CMML):
still ___% blasts in p.b.
<5
What bone marrow stain/s would we do for monos?
NSEs
What bone marrow stain would we do for myelocytes?
MPO and SBB (and maybe SE)
CMML:
The assay for what substance would you expect to be elevated in serum and urine?
lysozyme
Total WBC count with CMML?
increased!
Monos in bone marrow with CMML?
at least 20%
Total WBC count with RC, RARS, and RAFB?
normal to decreased
Monos in P.B. (AMC) with CMML?
> 1 x 10^3/uL
Blasts in bone marrow is _____% with RC and RARS.
<5
Blasts in bone marrow is ______ % with RAEB and CMML.
5-20
Dyserythropoiesis is seen with…
RC (especially) and RARS
Dysgranulopoisis is seen with…
RAEB, CMML
What disorders are Siderocytes/Sideroblasts seen with?
RC and RARS
+/- for RAEB
neg. for CMML
Dysmegakaryocytopiesis may be seen with…
RAEB or CMML
neg for RC and RARS
Ringed Sideroblasts in bone marrow is seen with…
RARs >15%
+/- for RC and RAEB
neg for CMML
Generalized Lab Findings for MDSs:
Pos. for Fe stains for bone marrow sideroblasts, like…
Prussian blue stain
Generalized Lab Findings for MDSs:
MPO/SBB and NSE stains all ________.
positive
Generalized Lab Findings for MDSs:
B12 and folate levels are ___________.
normal
Generalized Lab Findings for MDSs:
Most common abnormalities involve what chromosomes?
5, 7, 8, 11, 13, and 20
-Trisomy 8 and monosomy 7
Generalized Lab Findings for MDSs:
True or false?
genetic translocations are common.
False, rare!
MDS median survival varies from ____ to ____ years.
less than one year to greater than 6 years
MDS Prognosis & Treatment:
RC & RARS do better than ___________.
RAEB & RAEB-t
MDS:
Pts. can die from what complications? (not just from transforming into AML)
anemia, thrombocytopenia, OR neutropenia
MDS therapy depends on…
age, clinical severity, and cytogenetic picture
Only cure for MDS?
bone marrow transplant but BRMs (Biologic Response Modifiers) under investigation.
What does RC generally look like?
oval macrocytosis and nRBCs ie, megaloblastic old picture, with normal B12 and folate levels
What does RARS generally look like?
RA, + ringed sideroblasts in b.m.; RBCs look dimorphic
What does RAEB generally look like?
RA, + increased b.m. blasts, plus cytopenia in 2 cell lines, ANA bizarre WBCs!
What does CMML generally look like?
RA, +monos, AND blasts. AND LOTS of bizarre WBCs!
NSE 4+!