AML and MDS Flashcards
What usually happens with leukemia?
Usually moves out into the blood from the bone marrow
What is important about acute leukemia?
- SUDDEN ONSET
- Can occur in ADULTS or CHILDREN
- Rapidly fatal without treatment
- Composed of IMMATURE cells (blasts)
What is important about chronic leukemia?
- SLOW ONSET
- Occurs only in ADULTS (never kids, presents in over 20)
- Longer course (if you don’t treat it, sometimes patients will die of something else)
- Composed of MATURE cells
What does ALL, CLL, AML, CML stand for?
ALL - acute lymphoid leukemia
CLL - chronic “ “
AML - acute myeloid leukemia
CML - chronic “ “
Where does acute leukemia develop?
- Develops in precursor cells - cells you usually don’t see in periphery of the blood
- All you see is blasts in these two (acute lymphoblastic & myeloid apart!)
Where does chronic leukemia develop?
-Develops in end point cells - cells floating in the blood stream: basophil, eosinophil, monocytes, platelets, lymphocytes
Definition of Acute Leukemia:
-Malignant proliferation of immature myeloid or lymphoid cells in bone marrow
What is the cause of acute leukemia?
- Clonal expansion (they proliferate to a certain phase and then get “stuck”)
- Maturation failure
What makes acute leukemia so bad?
- It crowds out normal cells (with its clonal expansion)
- Inhibits normal cell function
- Infiltrates other organs (not very common, only happens in a few types)
Who is at higher risk for leukemia?
- People who touch benzene
- People with down syndrome
With acute leukemia most subtypes. . .
. . .are in the upper cells of the lineage (myeloid stem cell, lymphoid stem cell, myeloblast, pronormoblast).
What is the difference between acute lymphoblastic and acute myeloid leukemia on slide?
Cytoplasm is smaller and nucleus is darker purple and more dense in lymphoblastic than in myeloid.
What does acute leukemia look like in bone marrow biopsy?
- Bone marrow section is usually FULL of cells, very dense
- Cells grow so fast that they fill up the marrow in days or weeks
- Chronic leukemia is usually not so drastic
What are the clinical findings in acute leukemia?
- Sudden onset (days)
- Symptoms of bone marrow failure: fatigue, infections, bleeding
- Bone pain (expanding marrow)
- Organ infiltration (liver, spleen, brain)
What are the laboratory findings in acute leukemia?
- Blasts/immature cells in blood
- Leukocytosis (lots of WBC- mostly blasts or immature cells)
- Anemia
- Thrombocytopenia (low platelets)
What type of hematopoietic malignancy causes brain tumors (extra medullary tumor masses)? (KNOW)
AML - M5 (Acute Myeloid Leukemia)
What things MUST you know about acute myeloid leukemia?
- Malignant proliferation of myeloid blasts in blood, bone marrow
- 20% cutoff for diagnosis
- Many subtypes
- Bad prognosis
What is the old AML classificiation/FAB classification?
It’s based on morphology
M0 - acute myeloblastic leukemia, minimally diff.
M1 - acute myeloblastic leukemia, without maturation
M2 - acute myeloblastic leukemia, with maturation
M3 - acute promyelocytic leukemia
M4 - acute myelomonocytic leukemia
M5 - acute monocytic leukemia
M6 - acute erythroblastic leukemia
M7 - acute megakaryoblastic leukemia
What M#s of the old classification involve the neutrophilic series (myeloblasts, promyelocytes, etc.)?
M0, M1, M2, M3
What M#s of the old classification involve the monocytic series (monoblasts, etc.)?
M4, M5
What M#s of the old classification involve the erythroid series (erythroblasts)?
M6
What M#s of the old classification involve the megakaryocytic series (megakaryoblasts)?
M7
What percentage of blasts do you need for Acute Myeloid Leukemia?
AML - 20% blasts
What does acute myeloid leukemia look like on a blood smear?
- Very high leukocyte count (almost all malignant)
- WBC all look very similar
- Mostly blast cells (med to large size, high nucleus/cytoplasm ratio)
- Chromatin looks like nylon sock stretched out
How do you know when a leukemia is myeloid?
- Dysgranulopoiesis
- Auer rods
- Cytochemistry
- Immunophenotyping
- Cytogenetics
What is dysgranulopoiesis?
-When neutrophils around, they look odd/funny, not segmenting properly, one or two big lobes instead 4-5, chromatin is clumpy, cytoplasm doesn’t have specific granulation
What are auer rods?
- Long, needle-like structures
- Occur only in malignant myeloblasts (NEVER BENIGN CELLS)
- Rods formed by granules
What is cytochemistry?
- NSE - nonspecific esterase - stains monocytic cells
- If cells ‘light up’ then they are monocytic/myeloid in series
What do cytogenetics tell us?
Sometimes it’s important to know if there is a cytogenetic translocation for diagnosis purpose/prognosis purpose.
What are the five categories in the “New” AML classification?
- AML with genetic abnormalities
- AML with FLT-3 mutation
- AML with multilineage dysplasia
- AML, therapy-related
- AML, not otherwise classified
How do we classify the “AML, not otherwise classified”?
AML-M0-M7
What MUST you know about AML-M0?
- VERY HIGH myeloblasts
- Bland (no aur rods, granules)
- MPO negative
- Need markers (use flow cytometry to see what type of cells these are)
What do M0 cells look like on a slide?
- Many blasts
- Very fine chromatin
- No aur rods, no granules (bland blasts)
