Leukaemia

Question 1

What are the types of leukaemia

Answer 1

Myeloid:
Acute myeloid leukaemia (AML)
Acute Promyelocytic Leukaemia (APML)
Myelodysplasia
Myeloproliferative
Chronic myeloid leukaemia (CML)

Lymphoid:
Precursor: Acute lymphoblastic leukaemia (ALL)
Mature:
- Chronic lymphocytic leukaemia (CLL)
- Multiple myeloma
- Lymphomas: Hodgkin’s, non-hodgkin’s

Question 2

What are the features of acute leukaemia

Answer 2

Rapid onset
Early death if untreated (weeks or months)
Immature cells (blast cells)
Bone marrow failure → anaemia (pallor, fatigue, SoB), neutropoenia (infections), thrombocytopaenia (bleeding)

Question 3

What is the epidemiology of AML

Answer 3

Seen in adults (40%) and children < 2
Incidence increases with age, prognosis worsens with increasing age

Question 4

What is the aetiology of AML

Answer 4

1. Duplication (trisomy): trisomy 8 and trisomy 21
2. Inversion or translocation: t(8;21), inv (16), t(16;16) → fusion genes (RUNX1/RUNX1T1, CBG-beta/MYH11) → transcription factor function disturbance
3. Chr loss/deletion (most common): del (5q) or del (7q)

Monoblast/megakaryoblast/erythroblast

Question 5

What are the risk factors for AML

Answer 5

Familial or constitutional predisposition (e.g. Down syndrome)
Irradiation
Anti-cancer drugs
Cigarette smoking
Unknown

Question 6

What are the signs and symptoms of AML

Answer 6

Anaemia: SOB, lethargy, pallor
Thrombocytopenia: bleeding, bruising
Neutropenia: infections
Bone pain

Local infiltration: hepatosplenomegaly, Lymphadenopathy, testes/CNS, bone pain
± hyperviscosity (very high WCC) → retinal haemorrhage/retinal exudate

Question 7

What would investigations for AML show

Answer 7

Cytology: Auer rods, fin-speckled granules
Cytochemistry: stains with myeloperoxidase, Sudan Black stain
FBC: raised WCC
Blood film/BM aspirate: circulating blasts
Immunophenotyping: flow cytometry, immunocytochemistry, immunohistochemistry (determine AML from ALL)

Molecular studies and FISH (some patients) → enable sub-classification of the acute myeloid leukaemia and adds prognostic value and aids treatment decisions (certain cytogenetic findings aid prognosis)

Question 8

What is the management for AML

Answer 8

1. Supportive: red cells, platelets, FFP/cryoprecipitate, Abx, long line insertion, allopurinol
2. Chemotherapy
   - Danorubicin + cyfabine
3. Targeted molecular therapy
   - APML = All-trans-retinoic acid (ATRA) and A2O3
   - Biologics = anti-CD33 antibody linked to cytotoxic antibody (e.g. gemtuzumab)
4. SCT

Question 9

What is Acute Promyelocytic Leukaemia (APML)

Answer 9

t(15;17) → PML-RARA fusion gene → monocytic leukaemia
Acute myeloid leukaemia that causes sudden haemorrhage (DIC + hyperfibrinolysis)
± gum infiltration
± skin, CNS infiltration → CN palsy
Characterised by an excess of abnormal promyelocytes (Auer rods)

Question 10

What is the epidemiology of ALL

Answer 10

Children, 2-5yo
Most common childhood malignancy

Question 11

What is the aetiology of ALL

Answer 11

Lymphoblastic infiltration → B OR T cell lineages
Bone marrow → B-lineage
Thymus → T-lineage (more common)
85% are B-lineage, 5% T cell lineage

May get philadelphia chromosome +ve (Transformation from CML)

Question 12

What are the signs and symptoms of ALL

Answer 12

Children:
Bone marrow failure (anaemia, thrombocytopenia, neutropoenia)
Local infiltration
- Lymphadenopathy (± thymic enlargement)
- Splenomegaly
- Hepatomegaly
- Testes, CNS (these are ‘sanctuary sites’as chemotherapy cannot reach them easily)
- Bone (causing pain)

Adults: similar presentation to AML + lymphadenopathy ± thymic mass

Question 13

What may investigations show for ALL

Answer 13

FBC: Anaemia, Raised WCC (BUT Neutropenia), thrombocytopenia
>20% blasts
Film: high nucleus: cytoplasm ratio
Bone marrow biopsy

Immunophenotyping: differentiate between AML and LL AND between T and B lineage
Cytogenetic/molecular genetic analysis: Ph Chr +ve → imatinib

Question 14

What is the management for ALL

Answer 14

1. Supportive: blood products, Abx prophylaxis, hyperK+ Mx, hyperUricaemia Mx, central venous catheter)
2. Chemotherapy: systemic (2-3 years) + CNS specific
3. Molecular treatment
   - Ph +ve → imatinib
   - Rituximab (anti-CD20)
4. Transplant

Question 15

What is the prognosis of ALL

Answer 15

Children: 5-year disease-free survival of 80% (85% of children are cured)
Adults: 5-year disease-free survival of 30-40%
Prognosis worsens with increasing age
Prognosis is very dependent on cytogenetic/genetic subgroups: hyperdiploidy = good prognosis

Question 16

What is the epidemiology of CML

Answer 16

M>F
40-60yo peak (however, affects any age)
RF: radiation

Question 17

What is the aetiology of CML

Answer 17

BCR-ABL Ph Chr translocation t(9;22) → philadelphia chromosome (oncogenic novel fusion oncoprotein) → greater TK activity (ABL = TK)
→ proliferation of mature granulocytes → ↑ neutrophils, eosinophils, basophils

Question 18

What are the signs and symptoms of CML

Answer 18

Anaemia: lethargy, pallor, SOB
Infections
Bleeding, bruising
Splenomegaly (splenic infiltration)

Question 19

What is found on investigations for CML

Answer 19

FBC:
- Hb/Plt NORMAl/RAISED
- Massive leucocytosis (neutrophils 50-500), myelocytes, basophils
- Platelet count: raised
Blasts: No excess (<5%)
Blood film: mature myeloid cells
Conventional karyotyping: BCR-ABL
FISH
RQ-PCR - molecular response (reduction in BCR-ABL transcripts) - most sensitive

Question 20

What are the phases of CML

Answer 20

1. Chronic phase (5-6 years): <5% blasts
2. Leukocytosis phase: 500-5000 myeloid cells (neutrophils, myelocytes), bone marrow hypercellular
3. Accelerated phase (6-12 months): 10-19% blasts
4. Blast crisis: >20% blasts, survival 3-6 months

Question 21

What is the management for CML

Answer 21

Imatinib (tyrosine kinase-R inhibitor)
Monitor response (FBC, cytogenetics, RQ-PCR for complete cytogenic response (CCyR)
Second line: switch to other gen TK inhibitor
Third line: SCT

Other TK inhibitors: dasatinib, nilotinib, bosutinib

Question 22

What is CLL

Answer 22

Most common = proliferation of mature B cells
Risk of Richter transformation → Diffuse large B cell lymphoma

Question 23

What are the signs and symptoms of CLL

Answer 23

Indolent → often only picked up during routine blood tests (lymphocytosis)

Symmetrical lymphadenopathy
Splenomegaly
B symptoms (cyclical fevers, night sweats, weight loss)

Question 24

What may be found on investigation for CLL

Answer 24

FBC: Lymphocytosis (5-300 x 109/L), normocytic/normochromic anaemia, thrombocytopenia
Blood film: Smear cells (weak cells that break when put on a slide)
Immunophenotyping: third population of lymphocytes expressing CD19 AND CD5

Question 25

Describe the phenotype of B cells in CLL

Answer 25

Normal T cells are CD5 positive, and CD 19 and 20 negative. While normal B cells are the other way around. CLL B cells have an unusual phenotype - In CLL, the B cells continue to express CD5 (seen in the intermediate B cell) Monoclonal lymphocytosis with abnormal expression of CD5 = highly suggestive of CLL

Question 26

What is the prognosis for CLL

Answer 26

Initially 5-10 years good health until progression to a 2-3 year terminal phase 1/3 never progress 1/3 progress and respond to treatment 1/3 progress and die from CLL Good prognosis: LowZap70, 13q14 deletion BAD prognosis: 17p/TP53 mutation (MOST IMPORTANT), IgH unmutated (VH), raised LDH, CD38 +ve, 11q23

Question 27

What is the staging for CLL

Answer 27

Rai and Binet staging Binet: A: <3 lymphoid tissues B: >3 lymphoid tissues C: Hb <100, Plt <100 (+ B symptoms) Rai: 0: lymphocytosis only 1: lymphadenopathy 2: Hepatosplenomegaly 3: Hb <11 4: Platelets <100

Question 28

What is the management for CLL

Answer 28

1. Supportive (vaccination (no LIVE-ATT), Abx prophylaxis, IVIG, Antivirals 2. Leukaemia-directed treatment: - Watch and wait preferred in elderly - SCT in younger patients - Chemotherapy: ibrutinib (bruton tyrosine kinase inhibitor), venetoclax (Anti-Bcl2), CAR-T) Richter transformation → R-CHOP (high grade lymphoma treatment)