Week 2 - C - Malignant Haematology - Types of leukaemia, Overview of Acute myeloid/lymphoblastic leukaemia (diagnosis& Tx)

Question 1

The ability to differentiate into different lineages increases as you go down the cell lineage Once the lineage is establish, you cannot become a different lineage – this is the process of maturation Which cells in haemapoeisis are generally quite dormant and quiescent?

Answer 1

These would be the long term and short term haemapoietic stem cells

Question 2

When cells are mature and have lived their life span they will undergo apoptosis Arrange into order of haemaopoiesis * Maturaion * Apoptosis * Differentiate or lineage commitment * Self renewal * Proliferation Can cells change from lineage commitment or not? Which cells are capable of self renewal?

Answer 2

Self-renewal Proliferation Differentiation or lineage commitment Maturation Apoptosis Once committed to a lineage,, unable to change Only the LTandST HSC are capable of self renewal

Question 3

How do we identify more mature cells?

Answer 3

We identify more mature cells based upon their morphology - there is a combination of nuclear and cytoplasmic stains that can identify mature red cells on blood count and blood film

Question 4

• What are the black outline boxes underlying?
• WHat are the orange boxes underlying?
• What are the purple boxes uunderlying?
• What are the blue boxes underlying?

Answer 4

• Black outlined boxes - beneath neutrophils - can see the segemented nucleus with blueish cytoplasmic granules
• Orange box - Monocyte - has a horse shoe/kidney shaped nucleus
• Purple boxes - eosinophil -red cytoplasmic granules
• Blue boxes - this is a lymphocyte - may be activated

Question 5

When identifying precursor/progenitor/stem cells, immunophenotyping and cytochemistry can be used to identify the type of cell What do these two different methods analyse?

Answer 5

Immunophenotyping - analysis of the cell surface antigens Cytochemistry - analysis of the enzyme expression of cells

Question 6

Is immunophenotyping or cytochemistry more used in todays era of meidicne? What is the cell surface antigen expressed by HSC? What is the cell surface antigen expressed by Tcells? What is the cell surface antigen expressed by B cells? What is the enzyme expressed by neutrophils?

Answer 6

Immunophentyping is more commonly used today * CD34 - cell surface antigen expressed by HSC * CD3 - cell surface antigen expressed by T cells * CD20 - cell surface antigen expressed by B cells The enzyme expressed by neutrophils detectable on cytochemistry would be myeloperoxidase (MPO)

Question 7

How is immunophenotyping carried out?

Answer 7

Immunophenotyping involves the studies of specific lineages or stage of development of cells by using specific antigens to target cell surface antigens The antibodies are coated with a flurochorme dye of different colours and sent into the sample - they will bind to the cells which express their specific antigen and a laser software is used to identify the fluorochrome tag Can see which tag is more abundant and this points to the monoclonality disorder

Question 8

After finding the type of cell which is in abundance, good to understand what mutation may have occured and what type of analysis is involved here?

Answer 8

Cytogenetic analysis

Question 9

What happens in malignant haemopoiesis?

Answer 9

There is an increased number of abnormal and dysfunctional cells and these dysfunctional cells cause loss of normal activity

Question 10

The increased abnormal and dysfunctional cells can cause the loss of normal cell activity due to different mechanisms What are these mechanisms?

Answer 10

The loss of normal cell activity can be due to one or more of four reasons because of the increase in abnormal and dysfunctional cells: Increased proliferation Lack of differentiation Lack of maturation Lack of apoptosis

Question 11

State the ways in which dysfunctional cells can cause loss of normal cell activity again?

Normal bone marrow aspirate will reflect the normal kinetics of haemaopoeisis - aspirate is abnormal in maligannt haemopoiesis

• What are the normal kinetics of haemaopoiesis?

Answer 11

4 ways in which dysfucntional cells can cause loss of normal cell activity - one or more of:

• * Increased proliferation
• * Lack of differentiation
• * Lack of maturation
• * Lack of apoptosis

Normal kinetics = self renewal - proliferation - differentiation or lineage commitment - maturation - apopotisis On the normal aspirate above - can see morphological variance, precursors to neutrophils and other cell types

Question 12

Malignant haemopeoiesis would reflect an abnormal bone marrow aspirate What is leukaemia? What are the four main types of leukaemia?

Answer 12

Leukemia is a cancer of the blood and bone marrow The four main types are: Acute myeloid leukaemia Acute lymphoblastic leukamia Chronic myeloid leukaemia Chronic lymphocytic leukamia

Question 13

What is the difference between the acute and chronic leukaemias?

Answer 13

Both acute and chronic contain the proliferation of abnormal progenitors But In acute leukaemias there is a block in the differentiation/maturation of cells and therefore there is an increase in number of abnormal immature progenitor cells In chronic leukaemias there is no block in differentation/maturation and therefore there is an increase in the number of abnormal mature cells

Question 14

What would this patient have and why? Which of the four different types of reasons for the abnormal dynsfunctional cells causing loss of normal cell activity would be affected?

Answer 14

This would be an acute myeloid leukaemia - there is abnormal proliferation of progenitor myeloid cells with a block in the differentiation/maturation of the myeloid cells Increased proliferation of abnormal cells Lack of differentiation Lack of maturation

Question 15

This person has no block in maturation/differentiation but there is an increase in the proliferation of abnormal dysfunctional cells WHat might this patient have?

Answer 15

This patient could have Chronic myeloid leukaemia or Chronic lymphocytic leukaemia This patient will have increased proliferation - however no lack of differentiation or maturation

Question 16

Top patient - Acute leukaemia – there is an increase in cell numbers (proliferation) but– they all look the same Cannot spot the morphological distinction in these cells What type of chronic myeloproliferative disorder is a neoplasm?

Answer 16

This would be chronic myeloid leukemia Chronic myeloproliferative neoplasms are diseases in which the bone marrow makes too many red blood cells, platelets, or certain white blood cells.

Question 17

Acute lymphoblastic leukaemias affect which type of cell? Acute myeloid leukaemis affect which cell type? Chronic lymphocytic leukaemias affect which type of cell? Chronic myeloid leukaemias affect which cell type?

Answer 17

* Acute lymphoblastic leukaemiasaffect the immature T or B lymphocyte * Acute myeloid leukaemias affect the immature myeloid lineage cells * Chronic lymphocytic leukaemias affect mature B &T cells resulting in proliferation of mature cells * Chronic myeloid leukaemias affect the haemopoeitic stem cell/progenitor cells - result is still abnormal proliferation but there is no block on differentiate/maturation of the cells

Question 18

Haematological malignancies can be caused by varying things: * Genetics, epigenetics and environment may have an influence * Recurrent cytogenetic abnormalities - eg deletions or chromosomal translocations * Multpiple ‘hits’ or single catastrophic events * Somatic mutations in regulatory genes -driver vs passenger mutations - what is the difference between driver and passneger mutations?

Answer 18

Driver mutations are mutations in gene which control cell growth and therefore mutations usually result in abnormal proliferation (can be in ie tumour suppressor genes) Passenger mutations are in genes which do not control growth and therefore do not play a role in cancer

Question 19

Do haematological malignancies usually occur due to a single catastrophic event or multiple ‘hits’ to the cell?

Answer 19

A single catastrophic event is rare to cause cancer development Multiple hits to the cells are usually required to develop cancer

Question 20

What is a clone of cells?

Answer 20

A clone is a population of cells derived from a single parent cell

Question 21

Drive mutations can affect clones - affecting the population of cells derived from a single parent cell The parent cell has genetic markers (be it the drive mutation or chromosomal change) which is shared by all the daughter cells in the clone What type of investigation can be used to identify the driver mutation or chromosomal change?

Answer 21

Can use cytogenetics to investigate any of the gene abnormalities in the cell such as the driver mutation o the chromosomal change

Question 22

Clones can diversify but contain a similar genetic ‘backbone Normal haemopoiesis arises from a number of cell types - what is this known as? When a single cell starts to dominate, this is not good and what is it known as? What can having this increases in single cells cause?

Answer 22

Normal haemopoiesis is described as being polyclonal - when populations of cells arise from different parent cell When a single cell type starts to dominate - this signifies monoclonal division and this can cause malignant haemopoeisis to arise (increase in proliferation of abnormal and dysfunctional cells causing loss of normal activity)

Question 23

Do driver or passenger mutations confer the growth advantage of cells? Are cells that have driver or passenger mutations selected during the evolution of the cancer?

Answer 23

Driver mutations confer growth advantage of the cells and are selected during the evolution of the cancer cell Passenger mutations do not confer growth advantage of the cells

Question 24

The journey towards a malignant cell really starts from the moment of conception – The fertilised egg has an intrinsic mutation rate and can pick up passenger mutations along its genetic journey Why may passenger mutations therefore be present when these cells obtain a driver mutations?

Answer 24

Passenger mutations do not confer a growth advantage but may happen to be present in the ancestor of the cancer cell when it acquired one of its drivers Driver mutations will affect the growth regulation of the gene and cause the gene to become abnormal & dysfunctional

Question 25

Proof that somatic mutations (driver and passenger mutations) exist and can cause the cancer cells to develop Are the driver mutations or chromosomal changes present from birth in the children who will go on to develop leukaemias?

Answer 25

As shown in the picture there can be passenger mutations throughout the genetic lifespan but when a driver mutation or chromosomal change occurs - these cells will confer a growth advantage and are selected during evolution of the cancer So no - the driver mutations or chromosomal changes are not present at birth and are instead gene or chromosmal mutations that occur during life giving rise to cancer

Question 26

Types of haematological malignancies 1. Based on lineage 2. Based on developmental stage (precursor) within lineage 3. Based on anatomical site involved What are the two types of lineage for the haematological malignancies to arise from? When can malignancies occur in the developmental stages within the lineage?

Answer 26

Two types of lineage - myeloid or lymphoid lineages Malignancies can occur at any point in the lineage Can occur in the precursor immature cells or the mature cells

Question 27

The type of haematological malignancy also depends on the anatomical site affected * What are blood involvements categorised as? * What are lymph involvement categorised as? * Which type of haematological malignancy affecting the blood can involve both blood and lymph nodes? * What is the plasma cell malignancy originating in the bone marrow known as?

Answer 27

Blood involvement - leukaemias Lymph node involvement - lymphomas Chronic lymphocytic leukaemias can involve both the lymph nodes and blood Myeloma is the name for the plasma cell malignancy originating in the bone marrow

Question 28

Which type of leukaemias and lymphomas are typically more aggressive clinically and histologically?

Answer 28

Acute leukaemias and high-grade lymphomas are more aggressive typically than chronic leukaemias and low-grade lymphomas respectively

Question 29

What are the features of histological aggression? What are the features of clinical aggression?

What are the red arows in the pic pointing to? Clue it is an acute leukaemia - can see by the aggresive histological features

Answer 29

Histological aggression - large cells with high nuclear to cytoplasmic ration and prominent nucleoli with rapid proliferation

Clinical aggression - rapid progression of symptoms - bone marrow failure

Red arrows pointing to - Auer rods - Diagnostic of Acute Myeloid Leukaemia

Question 30

What are the four types of leukaemia? Where does the mutation in the cell normally arise?

Answer 30

Acute myeloid leukaemia - mutation arises in the myeloid lineages - immature myoclonal cells produced Chronic myeloid leukaemia -mutation arises in stem/progenitor cells leading to myoclonal cells Acute lymphoblastic leukaemia - mutation arises in lymphoblasts - immature T/Bcells - monoclonal still Chronic lymphocytic leukaemia - accumulation of mature B cells - monoclonal ie mature B in abundance

Question 31

Rapidly progressive clonal malignancy of the marrow/blood with maturation defect(s) WHat is this? What is the excess of blast cells in the blood film or bone marrow defined as for this malignancy?

Answer 31

Rapid clonal malignancy of the marrow/blood with maturation defects - acute leukaemia It is defined as an excess of blast cells >/= 20% in the blood film or bone marrow

Question 32

In acute leukaemias there is also a decrease/loss in haemopoietic reserve What are the types of acute leukaemia? Which of the 4 leukaemis is the commonest? Which one is the commonest type of childhood cancer?

Answer 32

This would be acute myeloid leukaemia or acute lymphoblastic leukaemia Chronic lymphocytic leukaemia is the commonest leukaemia Acute lymphoblastic leukaemia is the commonest type of childhood cancer

Question 33

WHat is acute lymphocytic leukaemia?

Answer 33

ALL is a malignant disease of the primitive lymphoid cells (Lymphoblasts) It is the most common childhood cancer and is rare in adults

Question 34

What is the clincial presentation of acute lymphoblastic leukaemia?

Answer 34

There is bone marrow failure resulting in Anaemia Leukopenia Thrombocytopenia - so children are more prone to bleeds, infections and also present pale and fatigued (can be seen in both ALL and AML)

Question 35

If there is high leukaemic counts on bloods, what can this cause in ALL? What can the ALL affect outside of the blood and marrow (extramedullary)? What are common infections for children with ALL to get?

Answer 35

If there are high leukaemic counts, this can cause obstruction of the circulation (WCCs are usually high on bloods in this) ALL can typically affect the CNS and testis causing CNS problems and orchidomegaly Common infections include zoster, recurrent chest infections and cellulitis

Question 36

Acute myeloid leukaemia is a malignant leukaemia of the primitive myeloid lineages What age group is it more common? What can it be a risk factor to? What is its clinical presentation?

Answer 36

Acute myeloid leukaemia is more common in those aged >60 years of age but can occur in younger age groups Risks factors for this can include previous exposure to chemotherapy Clincially present similiar to acute lymphblastic leukaemia with anaemia symptoms and bleeding and infections - usually less severe than ALL at presentation - often see pallor and petechia in this type

Question 37

Subgroups of acute myeloid lymphoma have characterisitc presentations such as Disseminated intravascular coagulation and gum infiltration What are these subtypes?

Answer 37

Acute promeylocytic leukaemia - disseminated intravascular coagulation Acute myelomonocytic leukaemia has gum infiltration (The type AML which produces monocytes has a tendency to infiltrate gums ) Mucosal surfaces such as gum eyes etc can bleed in either of the leukaemias

Question 38

Initially a blood count and film is taken followed by a coagulation screen WHat is seen on the count and film?

Answer 38

On blood film -there is the reduction in normal cells and the increase in abnromal cells The cells have large nuclear:cytoplasmic ratios and there is lots of proliferation, can also see clear nuceoli On blood count - anaemic, thrombocytopenic and neutropneic (although WCC may be raised)

Question 39

What is the diagnostic feature seen in blood film in acute myeloid leukaemia? How does it form? Although it is diagnostic, immunophenotyping still required as diagnosis to be sure

Answer 39

Can see Auer rods on morphology - these are clumps of granular material that form needle like shapes in the cytoplasm of myeloid leukaemic cells

Question 40

After looking at the blood film and coag studies have been carried out, it is important to take a bone marrow aspirate What three things are examined for on the bone marrow aspirate?

Answer 40

The morphology of the cells - what they look like Immunophenotyping - understand whether the cells are lymphoid or myeloid by the presence of a cell surface antigen Cytogentic testing to understand the cause of the mutation

Question 41

What is seen on morphology of the bone marrow in acute leukaemias? WHat is carried out after looking at their morphology?

Answer 41

On morphology -the cells are morpholically indistinct - therefore need immunophenotying to determine the cell types seen On immunophenotyping – we can tell if there is lineage specific proteins on the cell surface to tell whther the lineage is myeloid or lymphoblastic laukameia Must always do immunephentoyping before diagnosis Can find antigen only expressed on myeloid or lymphoblastic cells

Question 42

Even if cells from AML and ALL look alike, they will express lineage-associated proteins: immunophenotyping is required for a definitive diagnosis This has largely replaced cytochemistry as a diagnostic tool Why is cytogenetics carried out?

Answer 42

It is carried out to detect any chromosomal abnromalities as the presence of any abnormalities can affect treatment prognosis

Question 43

If a sub-optimal bone aspirate is taken, what can be carried out to aid in the investigations?

Answer 43

Trephine (piece of bone)-enables better assessment of cellularity and helpful when aspirate sub-optimal

Question 44

What is given as the curative management of acute lymphoblastic leukaemia and acute myeloid leukaemia? How long does each treatment last?

Answer 44

Multiagent chemo for both types Acute lymphoblastic leukaemia - Mutli-agent chemo which can last up to 2-3 years Acute myeloid leukaemia - 2-4 cycles of multi-agent chemo given in one week blocks with 2-4weeks rest between cycles Treatment can last quite a few months

Question 45

What is the line inserted into the patient to allow for IV access to deliver a treatment?

Answer 45

A hickmann line

Question 46

CNS prophylaxis is given in acute lymhoblastic leukaemia What is given here?

Answer 46

This would be intrathecal methotrexate

Question 47

Patients usually die very quckly of gram negative bacteria when patients are neutrpenic What is neutropenic sepsis? if suspecting neutropenic spesis, what is carried out?

Answer 47

Neutropenic sepssi - sepsis + neutropenia <0.5 or less than 1 if chemotherapy within the last 21 days (assume they are neutropenic if having recieved chemo in the past 3 weeks)

Question 48

What is given to treat the neutropenic sepsis? What else apart form the anemia and neutropenia can the marrow suppression cause?

Answer 48

Piperacillin and tazobactam The marrow suppresion can cause thrombocytopenia - bleeding Purpura and petechia (when <20x10^9/L)

Question 49

Chemotherapy can have lots of side effects also What are the side effects?

Answer 49

Nausea and vomiting Hair loss Liver and renal dysfunction Tumour lysis syndrome Also Infection (bacterial, fungal or protozoal)

Question 50

Tumour lysis syndrome can occu and usually during the first course of treatment this occurs Tumor lysis syndrome (TLS) is a group of metabolic abnormalities that can occur as a complication during the treatment of cancer,[1] where large amounts of tumor cells are killed off (lysed) at the same time by the treatment, releasing their contents into the bloodstream. What drug can be give with the first dose of chemo in ALL and AML to prevent this?

Answer 50

Give allopurinol to prevent tumour lysis syndrome - it should be given prophylactically to chemo in this condition

Question 51

Infection Bacterial: empirical treatment with broad spectrum antibiotics (particularly covering Gram negative organisms) as soon as neutropenic fever (IMPORTANT!) Fungal (if prolonged neutropenia and persisting fever unresponsive to anti-bacterial agents) (IMPORTANT!) What is given for the antibitoics for neutropenic sepssi? What is given for antifungal cover in neutropenia? WHat is a type of fungus that can present?

Answer 51

Antibitoics - pipercillan and tazobactam Antifungal - itraconazole - could be eg aspergillus or pneumocystic pneumonia (caused by pneumocysit jiroveci fungus) If PCP -give high dose co-trimoxazole

Question 52

Is treatment worth the effort?! Many patients will go into remission, what is this defined as/

Answer 52

Haematological remission means there is no evidence of leukaemia in the blood, a normal or recovering blood film and <5% blasts in a normal regenerating marrow

Question 53

Unfortunately remissions may not durable depending on the type of acute leukaemia and many patients will relapse Some patients will die of treatment-related toxicity Childhood acute lymphoblastic leukaemai is one of the highest success rates now That success inchildren has not been transferred to adults unfortunately Is acute myeloid leukamia treatment more successful in adults above or below 60?

Answer 53

Adult acute myloid leukameia however is more successful if under 60 than if over 60

Question 54

The philadelphia chromosome (although mainly seen in chronic myeloid leukaemia) can be seen in ALL Cytogenetic analysis is carried out to detect this type of chromsomal change What is given as treatment if this is present?

Answer 54

Give a tyrosine kinase inhibitor known as imatinib

Question 55

An AML sub-type (acute promyelocytic leukaemia) has a specific chromosomal translocation t(15;17) and is associated with what bleeding disorder? What can be given as treatment?

Answer 55

Associated with disseminated intravascular coagulopathy Can give vit A analogues and arsenic to treat acute promyeloid leukaemias

Question 56

One more time, what is the difference in treatment of ALL and AML? What is given to prevent tumour lysis syndrome in both?

Answer 56

ALL - 2-3 years treatment of multi-agent chemotherapy AML - 2-4 cycles of multi-agent chemo treatment - each cylce lasts rouhgly one week and 2-4 weeks rest between each cycle Give allopurinol to prevent tumour lysis syndrome in both both types of leukaemia, younger patients have better prognosis