Acute Leukemias- Biology, Clinical Features, and Therapy Flashcards
What is not a common symptom of acute leukemia?
Fever Nose bleeding Fatigue Hearing loss Rash
hearing loss (cholormas (masses of leukemia cells) can form around ears but rare
True of false: acute myeloid leukemia and acute lymphoid leukemia can be easily differentiated by review of the peripheral blood smear?
False
Which of the following tests are important in diagnosing and treating acute leukemias?
Bone marrow biopsy Flow cytometry Cytogenetics Molecular analysis All of the above
All of the above
What are leukemias?
Group of heterogenous disorders characterized by the accumulation of malignant white cells in the BM and blood. These abnormal cells cause morbidity and mortality because of:
1) BM failure: anemia, neutropenia, thrombocytopenia
2) Infiltration of organs: liver, spleen, lymph nodes, meninges, brain, skin or testes
What is the patient population in ALL?
Most common form of leukemia in children
its incidence is highest at age 3 to 7 years, falling off by 10 years and then a smaller secondary rise by age 40 years
What is the patient population in AML?
It is the most common form of acute leukemia in adults and is increasingly common with age.
What is the difference clinically between primary AML (de novo) and secondary AML (develops from MDS or other hematatological malignancies)?
Secondary AML is more difficult to treat (part of it is the older patient population)
Which of the following are major causes of AML?
A) Smoking B) Chemotherapy C) Pre-existing hematological disorder such as myelodysplastic syndrome D) All of the above E) Answers B & C
E) Answers B and C
smoking is associated with chronic monocytic leukemia
What are some main causes of acute leukemia?
- Idiopathic (vast majority)
- Prior chemotherapy/radiotherapy
- Chemical exposure (benzene)
- Myelodysplastic syndromes
- Myeloproliferative diseases
- Down’s syndrome
- Fragile chromosome syndromes (Fanconi’s anemia)
- Aplastic anemia and PNH
T or F. Acute leukemias are aggressive diseases that can rapidly cause death if not treated
T.
Where does the malignant transformation occur in acute leukemias?
in hematopoietic stem cells or early progenitors
Genetic damage leads to:
(1) increased rate of proliferation
(2) reduced apoptosis
(3) block in cellular differentiation.
Collectively these events result in accumulation of early BM hematopoietic cells known as ‘blast’ cells
What is acute leukemia defined as?
20+% blasts in blood or BM (less than 20%= MDS)
Can also be diagnosed with less than 20% if cytogenetic abnormalities are present
How is AML differentiated from ALL?
Most useful: Immunological markers (flow cytometry).
Morphologically, presence of auer rods is diagnostic of AML.
Chromosomes and genetic analysis can be useful
What are some myeloid antigens used to ID AML?
-Myeloid antigens include MPO, CD33, CD13, HLA-DR
What are some lymphoid antigens used to ID ALL?
-Lymphoid antigens include TdT, CD10, CD19, CD20
21 year old African American female presents with
nose bleeding
coagulopathy with elevated INR and decreased fibrinogen,
white blood count of 2.0, hemoglobin of 8.1 and platelet count of 43, with blasts present on peripheral smear.
What is the most likely diagnosis?
A) Acute lymphoblastic leukemia
B) Aplastic anemia
C) Acute erythroblastic leukemia
D) Acute promyelocytic leukemia (M3 AML)
D) Acute promyelocytic leukemia (M3 AML)
What is likely to be found on cytogenetics?
A) Chromosome 9,22 translocation
B) Chromosome 15,17 translocation
C) Chromosome 7 deletion
D) Normal cytogenetics
B) Chromosome 15,17 translocation (PML-RARa fusion)
Case. A 40 year old Hispanic male presented with easy bruising, tiredness and sore throat. On examination he had bleeding gums and pallor. Spleen tip was palpable.
His CBC came back with Hb 7gm/dl, WBC 50 x103/dl, platelet 75 x 103/dl. Peripheral smear showed numerous blasts cells with a single Auer rods in some of them. PT, aPTT, INR, Fibrinogen and D-Dimers were within normal range.
Immunophenotyping is positive for CD13, CD33, CD34, CD7, CD 117 and Myeloperoxidase and is negative for CD2, CD3, CD19, CD10, TdT.
Differential from bone marrow showed 60% blasts, nuetrophils 30%, promyelocytes 2%, monocytes 4%, myelocytes 3%, eosinphils 1%
Cytogenetics showed t(8;21) and –Y.
He has 4 siblings who are healthy
He has acute myeloid leukemia FAB M2 on morphology with t(8;21) and –Y. Molecular analysis showed no evidence of c. kit mutation.
What risk group is this patient’s AML?
A) Better risk
B) Standard or intermediate risk
C) Poor risk group
A) Better risk
loss of Y chromosome is common in leukemia patients and not that important
What is the appropriate treatment?
A) No further therapy needed
B) Induction chemotherapy followed by 4 cycles of consolidation chemotherapy
C) Induction chemotherapy followed by allogeneic stem cell transplant
D) Allogeneic stem cell transplant alone.
B) Induction chemotherapy followed by 4 cycles of consolidation chemotherapy
side effects of SCT should be avoided when possible (better risk AML)
What is the appropriate treatment for AML?
Remission induction therapy: 1 to 2 courses of intensive therapy to achieve a complete response (absence of detectable leukemia cells)
Post-remission therapy:
consolidation therapy: 3 to 4 courses of intensive short- course therapy to further reduce the subclinical body burden of tumor
Followed by (in some patients): maintenance therapy: months to years of less intensive therapy to further prevent recurrence or allogeneic bone marrow transplantation
Which ALL patient has the worst prognosis?
A) An 8 year old with ALL with E2a-PBX (chr 1,19) translocation on cytogenetics
B) A 21 year with T-ALL and normal cytogenetics
C) A 16 year old with TEL-AML1 (chr 12,21) translocation on cytogenetics
D) A 51 year old with BCR-ABL1 (chr 9,22) translocation on cytogenetics
D) A 51 year old with BCR-ABL1 (chr 9,22) translocation on cytogenetics
older age= worse prognosis
best prognosis: A>C>B>D
In both adult and childhood ALL, ____ and ____ translocations are associated with poor outcome
MLL-AF4 and BCR-ABL
In childhood ALL, what genetic abnormalities are associated with a good outcome?
hyperdiploidy, E2A-PBX, and TEL-AML
In adults these genetic abnormalities are rare
How is ALL treated?
Three treatment phases:
- Remission induction
- Consolidation (intensification)
- Maintenance
CNS prophylaxis (lumbar puncture)
What is used to counter hyperuricemia from tumor cell breakdown (TLS) in ALL therapy?
Allopurinol
What is cure rate in ALL?
70-85% cure rate in children, worse prognosis in adults of 40%
possibly related to worse genetic features
What remission induction drugs are used in ALL therapy?
VCR, L-ASP, DEX or PRED +/- Daunorubicin
What consolidation drugs are used in ALL therapy?
Daunorubicin, HD Ara-C, VCR, Etoposide, thioguanine or 6-mercaptopurine, cyclophosphamide, L-ASP
What drugs are used in ALL therapy for CNS prophylaxis?
intrathecal MTX or ARA-C
What maintenance drugs are used in ALL therapy?
6-MP, MTX, prednisone
