Acute Myeloid Leukaemia

Question 1

What is Acute Myeloid Leukaemia (AML)?

Answer 1

A cancer of the primitive (immature) myeloid line of blood cells, affecting procussor cells for granulocytes, monocytes, erythrocytes, or platelets

Question 2

In which age group is AML most common?

Answer 2

In the elderly, particularly those over 60 years old

Question 3

What are the two main types of AML origins?

Answer 3

(1) De novo AML (new onset)

(2) Secondary AML (transformation from a myeloproliferative disorder)

Question 4

What are the hallmark features of AML presentation?

Answer 4

Marrow failure symptoms, including
(1) anaemia
(2) infections
(3) bleeding
(4) easy bruising and petechiae (small red or purple spots)

Question 5

Which AML subtype is associated with coagulation defects or disseminated intravascular coagulation (DIC)?

Answer 5

Acute promyelocytic leukaemia

Question 6

In which AML subtypes is gum infiltration commonly seen?

Answer 6

Acute monocytic leukaemia and acute myelomonocytic leukaemia

Question 7

What is the diagnostic threshold for blasts in acute leukaemia?

Answer 7

≥20% blasts in the peripheral blood or bone marrow

Question 8

What characteristic feature is seen in AML blast cells on a blood film?

Answer 8

Auer rods inside the cytoplasm

Question 9

Why is immunophenotyping important in diagnosing AML?

Answer 9

It is required for definitive diagnosis, as AML and ALL cells look similar

Question 10

What tests are performed on a bone marrow aspirate in AML?

Answer 10

(1) Morphology
(2) Immunophenotyping
(3) Cytogenetics

Question 11

What is the standard treatment approach for AML?

Answer 11

Multi-agent chemotherapy, typically 2-4 cycles, requires prolonged hospitalisation

Question 12

What is a Hickman line used for in AML treatment?

Answer 12

Long-term central venous access during chemotherapy

Question 13

What are the primary complications of AML itself?

Answer 13

(1) Anaemia: Causing fatigue and weakness.

(2) Neutropenia: Leading to severe infections, especially from gram-negative bacteria and fungi.

(3) Thrombocytopenia: Resulting in bleeding (purpura, petechiae)

Question 14

What is the empirical treatment for neutropenic fever in AML?

Answer 14

Broad-spectrum antibiotics, particularly targeting gram-negative bacteria

Question 15

What is Tumour Lysis Syndrome, and when does it occur?

Answer 15

A life-threatening condition caused by rapid cell breakdown, often during the first course of treatment

Question 16

What are some late complications of AML treatment?

Answer 16

(1) Loss of fertility.

(2) Cardiomyopathy (e.g., from anthracyclines).

(3) Persistent infections like Pneumocystis jirovecii pneumonia (PJP)

Question 17

How does myeloid leukaemia differ from lymphocytic leukaemia?

Answer 17

Myeloid leukaemia commonly arises from a myeloid precursor cell, such as neutrophils, however lymphocytic leukaemia arises from a lymphoid precursor, such as B-cells

Question 18

What is the defining feature of acute leukaemia?

Answer 18

A block in differentiation at the precursor stage leading to a large number of malignant precursor cells accumulating in the bone marrow

Question 19

A 30-year-old male presents with fatigue and bruising. Bone marrow biopsy shows the presence of large numbers of abnormal promyelocytes (neutrophil precursors) but very few mature neutrophils.
Cytogenetics reveal a t(15;17) translocation is also present.

Given the findings what is the most likely diagnosis. Explain why?

Answer 19

Acute Myeloid Leukaemia

= AML is characterised by a block in differentiation at a precursor stage leading to a large number of malignant pro-myelocytes accumulating in the bone marrow. This accounts for the bruising as patients with AML lack platelets, which hinders clotting

Question 20

What are the clinical features of AML?

Answer 20

(1) Gum infiltration
(2) Disseminated intravascular coagulation (DIC) in acute promyelocytic leukaemia

(3) More common to see skin nodules

Question 21

A 66-year-old male presents to the GP with shortness of breath on exertion and fatigue for the last few weeks. On examination, he has petechiae and splenomegaly.

Blood tests are ordered which show ↓haemoglobin (Hb), ↑white cell count (WCC), ↓platelets

He is referred to a specialist where a bone marrow biopsy is performed which shows high numbers of blast cells and Auer rods.

What is the most likely diagnosis?

Answer 21

Acute myeloid leukaemia (AML)

= mentions auer rods

Question 22

Define Thrombocytopenia

Answer 22

low platelet count on a blood test

= Normal: 150,000–450,000/µL
(150–450 × 10⁹/L)

Question 23

NICE advise considering an urgent FBC (within 48h) to assess for leukaemia in adults with any of the following -

Answer 23

Pallor
Persistent fatigue
Unexplained fever

Unexplained persistent or recurrent infection

Generalised lymphadenopathy
Unexplained bruising
Unexplained bleeding
Unexplained petechiae
Hepatosplenomegaly

Question 24

A 63-year-old man presented with severe fatigue and recurrent bruising.
A bone marrow biopsy revealed hypercellularity and the presence of blasts (65%). For acute myeloid leukaemia, what is the cytogenetic abnormality?

Answer 24

t(15;17) translocation

Question 25

What are the genetic mutations or chromosomal translocation found in patients with AML

Answer 25

1 - t(8;21
2 - t(15;17)
= Associated with acute promyelocytic leukaemia (APL), a subtype of AML

Question 26

Why is the normal range of lymphocytes and the absence of basophils and eosinophils important in differentiating between AML and CML?

Answer 26

The normal lymphocyte count and absence of basophils/eosinophils suggest AML, as CML typically shows elevated basophils and eosinophils

Question 27

In a 71-year-old woman with myelodysplastic syndrome, unexplained fever, bruising, gum bleeding, and 25% blast cells with Auer rods on bone marrow aspirate, which is the most important prognostic factor?

Answer 27

(1) Cytogenetic type
= Key for prognosis in AML.

(2) Percentage of blast cells
= Higher blasts = worse prognosis.

(3) Performance status
= Affects treatment response.

(4) Age
= Older age worsens prognosis.

(5) Cell type (FAB classification)
= Less important than other factors.