AML and MDS

Question 1

What usually happens with leukemia?

Answer 1

Usually moves out into the blood from the bone marrow

Question 2

What is important about acute leukemia?

Answer 2

• SUDDEN ONSET
• Can occur in ADULTS or CHILDREN
• Rapidly fatal without treatment
• Composed of IMMATURE cells (blasts)

Question 3

What is important about chronic leukemia?

Answer 3

• 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

Question 4

What does ALL, CLL, AML, CML stand for?

Answer 4

ALL - acute lymphoid leukemia
CLL - chronic “ “
AML - acute myeloid leukemia
CML - chronic “ “

Question 5

Where does acute leukemia develop?

Answer 5

• 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!)

Question 6

Where does chronic leukemia develop?

Answer 6

-Develops in end point cells - cells floating in the blood stream: basophil, eosinophil, monocytes, platelets, lymphocytes

Question 7

Definition of Acute Leukemia:

Answer 7

-Malignant proliferation of immature myeloid or lymphoid cells in bone marrow

Question 8

What is the cause of acute leukemia?

Answer 8

• Clonal expansion (they proliferate to a certain phase and then get “stuck”)
• Maturation failure

Question 9

What makes acute leukemia so bad?

Answer 9

• 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)

Question 10

Who is at higher risk for leukemia?

Answer 10

• People who touch benzene

- People with down syndrome

Question 11

With acute leukemia most subtypes. . .

Answer 11

. . .are in the upper cells of the lineage (myeloid stem cell, lymphoid stem cell, myeloblast, pronormoblast).

Question 12

What is the difference between acute lymphoblastic and acute myeloid leukemia on slide?

Answer 12

Cytoplasm is smaller and nucleus is darker purple and more dense in lymphoblastic than in myeloid.

Question 13

What does acute leukemia look like in bone marrow biopsy?

Answer 13

• 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

Question 14

What are the clinical findings in acute leukemia?

Answer 14

• Sudden onset (days)
• Symptoms of bone marrow failure: fatigue, infections, bleeding
• Bone pain (expanding marrow)
• Organ infiltration (liver, spleen, brain)

Question 15

What are the laboratory findings in acute leukemia?

Answer 15

• Blasts/immature cells in blood
• Leukocytosis (lots of WBC- mostly blasts or immature cells)
• Anemia
• Thrombocytopenia (low platelets)

Question 16

What type of hematopoietic malignancy causes brain tumors (extra medullary tumor masses)? (KNOW)

Answer 16

AML - M5 (Acute Myeloid Leukemia)

Question 17

What things MUST you know about acute myeloid leukemia?

Answer 17

• Malignant proliferation of myeloid blasts in blood, bone marrow
• 20% cutoff for diagnosis
• Many subtypes
• Bad prognosis

Question 18

What is the old AML classificiation/FAB classification?

Answer 18

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

Question 19

What M#s of the old classification involve the neutrophilic series (myeloblasts, promyelocytes, etc.)?

Answer 19

M0, M1, M2, M3

Question 20

What M#s of the old classification involve the monocytic series (monoblasts, etc.)?

Answer 20

M4, M5

Question 21

What M#s of the old classification involve the erythroid series (erythroblasts)?

Answer 21

M6

Question 22

What M#s of the old classification involve the megakaryocytic series (megakaryoblasts)?

Answer 22

M7

Question 23

What percentage of blasts do you need for Acute Myeloid Leukemia?

Answer 23

AML - 20% blasts

Question 24

What does acute myeloid leukemia look like on a blood smear?

Answer 24

• 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

Question 25

How do you know when a leukemia is myeloid?

Answer 25

• Dysgranulopoiesis
• Auer rods
• Cytochemistry
• Immunophenotyping
• Cytogenetics

Question 26

What is dysgranulopoiesis?

Answer 26

-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

Question 27

What are auer rods?

Answer 27

• Long, needle-like structures
• Occur only in malignant myeloblasts (NEVER BENIGN CELLS)
• Rods formed by granules

Question 28

What is cytochemistry?

Answer 28

• NSE - nonspecific esterase - stains monocytic cells

- If cells ‘light up’ then they are monocytic/myeloid in series

Question 29

What do cytogenetics tell us?

Answer 29

Sometimes it’s important to know if there is a cytogenetic translocation for diagnosis purpose/prognosis purpose.

Question 30

What are the five categories in the “New” AML classification?

Answer 30

• AML with genetic abnormalities
• AML with FLT-3 mutation
• AML with multilineage dysplasia
• AML, therapy-related
• AML, not otherwise classified

Question 31

How do we classify the “AML, not otherwise classified”?

Answer 31

AML-M0-M7

Question 32

What MUST you know about AML-M0?

Answer 32

• VERY HIGH myeloblasts
• Bland (no aur rods, granules)
• MPO negative
• Need markers (use flow cytometry to see what type of cells these are)

Question 33

What do M0 cells look like on a slide?

Answer 33

• Many blasts
• Very fine chromatin
• No aur rods, no granules (bland blasts)