73. Leukemia

Question 1

Leukemia: epidemiology

Answer 1

• Boys > girls
• ALL > AML
• White > Black
• 25% of all malignancies

Question 2

Etiology

Answer 2

GENETIC FACTORS:

• Fanconi
• Ataxia telngiectasis
• Down’s syndrome

VIRAL:

• EBV

ENVIRONMENTAL:

• Radiation
• Preg mother smokes marijuana

Question 3

Pathophysiology

Answer 3

Uncontrolled proliferation of:

• Myeloblasts —> AML
• Lymphoblasts —> ALL

Question 4

Morphology of cells:

Answer 4

• Undifferentiated
• Split unclear chromatin
• Basophilic cytoplasm

Question 5

Classification of ALL:

Answer 5

1) Lymphocytoid

2) Lymphoblastoid

3) Burkitt

Question 6

Classification of AML

Answer 6

M0 = Minimally differentiated
M1 - Myeloblastic w/o maturation
M2 = Myeloblastic w maturation
M3 = Hypergranular promyelocyte
M4 = Myelomonocytic
M5 = Monocytic
M6 = Erythroleukemia
M7 = Metakaryoblastic

Question 7

CF:

Answer 7

INCREASED LYMPHOBLASTS + MYELOBLASTS IN:

• Bone marrow —> Pancytopenia + Bone pain
• Gingiva —> hyperplasia
• Lymph nodes —> Lymphadenopathy
• CNS —> headaches, blurry vision, Decreased balance
• Liver + spleen —> Hepatosplenomegaly
• Mediastinum —> SVCS
• Tumor lysis syndrome —> Release of contents —> Imbalances in calcium potassium phosphate —> Arrhythmias, muscle weakness, seizures

Question 8

Diagnosis

Answer 8

1) CF

2) CBC —> Pancytopenia

3) Peripheral blood smear —> Increased lymphoblasts = ALL, Increased myeloblasts = AML

4) Bone marrow biopsy —> ALL = > 20% lymphoblasts, AML = > 20% myeloblasts

5) Flow cytometry —> CD 10, CD 20 = B cell ALL / CD2, CD 8 = T cell ALL / CD 13, CD33 = AML

Question 9

Prognosis of ALL

Answer 9

GOOD:

• 1-9 yrs
• WBC count = < 50 x 10^9 /L
• Girls
• trisomy t

BAD:

< 1 yrs old

• WBC = > 50 x 10^9 / L
• Boys
• t ( 9 : 22 )

Question 10

Treatment:

Answer 10

ALL CHEMO = CVAD

• Cyclophosphamide
• Vincristine
• Adenomycin
• Dexamthasone

AML:

• Chemo = Daunorubicin
• Hematopoietic stem cells

COMPLICATIONS

• If Tumor lysis syndrome —> Allopurinol, IV fluids
• If WBC is very high —> Hydroxyurea
• Intrathecal chemo —< Prevents meningeal leukemia