Haem Malignancies

Question 1

What do myeloid precusor cells give rise to?

Answer 1

1. Granulocytes:
   - basophils
   - neutrophils
   - eosinophils
   - mast cells
   - monocytes –> macrophages
2. RBCs
3. Megakaryocytes –> platelets bud off

Question 2

What do common lymphoid precusors give rise to?

Answer 2

Lymphocytes:

• B cells
• T cells
• NK cells

*dendritic cells can arise from either this pathway or as part of granulocytes (from myeloid precursor)

Question 3

Bone marrow samples - types and preferred sites

Answer 3

1. bone marrow aspirate: takes a little of the liquid found in the bone marrow space
2. bone marrow biopsy (trephine): takes a small sample of harder bone marrow tissue.

Preferred sites:

• iliac crest (anterior or posterior)
• tibia
• sternum

Question 4

Acute leukaemia - definition

Answer 4

Neoplastic disease of immature blood cells (blasts) in the bone marrow. Can arise from myeloid or lymphoid lineage

Question 5

Acute leukaemia - general features

Answer 5

• Tiredness, infection, bruising/bleeding
• High white cell count
• Low haemoglobin (anaemia)
• Low platelet count (thrombocytopenia)
• Low neutrophil count (neutropenia)
• High WCC due to infections

Question 6

Acute leukaemia and infections

Answer 6

• Low neutrophil count (neutropenia) –> increased risk of infection (febrile neutropenia)
• chemotherapy –> mucositis (risk of mouth infections)
• Indwelling central venous line –> line infection (staph aureus)

Question 7

Acute myeloid leukaemia (AML) - features

Answer 7

• mainly >65 years
• RF: Radiation, previous chemotherapy, congenital syndromes, previous myelodysplastic syndrome
• Tiredness, infection, bleeding, ecchymoses or petechiae
• auer rods on blood smear

Question 8

What are auer rods?

Answer 8

Auer rods are cytoplasmic inclusions which result from an abnormal fusion of the primary granules.

• seen in acute myeloid leukaemia
• found on blood smear

Question 9

Acute lymphoblastic leukaemia (ALL) - features

Answer 9

• 30% of childhood cancer
• 20% of adult acute leukaemia
• RF: Radiation, Downs syndrome, M>F
• +ve philadelphia chr common in adults

Symptoms and signs

• Tired, anaemic, bruising, bleeding and low platelets, weight loss
• Abdominal pain, lymphadenopathy, splenomegaly

Question 10

What is the relevance of the philadelphia chromosome?

Answer 10

Cytogenetic abnormality results from chromosomal translocation t(9;22)(q34;q11) on the Philadelphia chromosome, found on molecular studies in:

1. Chronic myeloid leukaemia (95%) - pathognomonic
2. most common cytogenic abnormality in adult ALL

Question 11

AML - treatment

Answer 11

• 3 to 4 cycles of combination chemotherapy

- Haemopoietic stem-cell transplant (HSCT) for some

Question 12

ALL - treatment

Answer 12

• Induction (includes prednisolone/dexamethasone and vincristine) and consolidation chemotherapy (high-dose)
• HSCT or 2 years of maintenance therapy
• CNS prophylaxis throughout as can progress to/relapse in brain and spinal cord so intrathecal chemo +/- radio
• If Philadelphia positive ALL- also give Imatinib(Glivec)
• consider fluids, Abx prophylaxis, RBC transfusion etc

Question 13

Acute vs Chronic leukaemia

Answer 13

ACUTE: no mature cells (blasts) therefore low neutrophils, lymphocytes etc.
CHRONIC: mature cells affected therefore high neutrophils, lymphocytes

Question 14

Chronic leukaemia - def and types

Answer 14

Neoplastic disease of mature white blood cells in the bone marrow
Types:
- Chronic myeloid leukaemia (CML): overlaps with myeloproliferative disorders
- Chronic lymphocytic leukaemia (CLL): overlaps with lymphomas

Question 15

Chronic lymphocytic leukaemia (CLL) - features

Answer 15

• Majority of pts > 60 (most common type in adults)
• Slow accumulation of CLL cells in blood, bone marrow, lymph nodes, liver, spleen
• Hepatosplenomegaly and lymphadenopathy
• B symptoms: night sweats, persistent fever, weight loss, itching
• +/- bleeding/easy bruising and anaemic
• Can transform to high grade lymphoma (5%)

Question 16

CLL - Dx and treatment

Answer 16

Diagnosed by FBC with differential (absolute lymphocytosis, can have normal or low Hb and platelets), blood smear showing smudge cells, and flow cytometry

Treatment

• Observation (early stage) or Chemotherapy
• If not working or relapse, then use biological agents (Antibody therapy eg. Alemtuzumab, Rituximab)
• Last resort is allogeneic stem-cell transplantation

Question 17

CLL progressing to lymphoma - presentation

Answer 17

similarly to CLL the lymphocyte count is high but when progession to lymphoma occurs the Hb level goes really low and the patient is anaemic

• sudden onset of B symptoms
• progressive lymphadenopathy
• high serum levels of lactate dehydrogenase

Question 18

Chronic Myeloid Leukaemia

Answer 18

• Median age 50-60yrs old
• Philadelphia chromosome: most commonly associated with CML ( 95%)
• 20-50% asymptomatic (‘incidental’ finding on FBC)
• Splenomegaly, Bony pain
• Peripheral blood and BM demonstrates the presence of BCR-Abl fusion gene
• can progress to acute leukaemia (‘blast crisis’)
• Rx: Imatinib or other Tyrosine kinase inhibitors

Question 19

Myeloproliferative disorders

Answer 19

Over-production of mature blood cells

↑ Neutrophils = chronic myeloid leukaemia (CML)
↑ Red cells = polycythaemia rubra vera (PRV)
↑ Platelets = essential thrombocytosis (ET)
↑ fibroblasts = Idiopathic myelofibrosis: results in replacement of bone marrow/other sites with collagen

Question 20

Myelodysplasia (myelodysplastic syndrome - MDS)

Answer 20

Pre-cancerous disease of bone marrow, where the dysplastic cells may cause abnormal blood cell production (bone marrow trying to compensate)

• Consider this in patients with abnormal blood counts with no obvious explanation (e.g. macrocytic anaemia)
• Dysplastic morphology
• Almost exclusively patients over 60
• Can also progress to acute leukaemia

Question 21

Myeloma - definition

Answer 21

Neoplastic disease of plasma cells (activated B cell - antibody producing)

Leads to increase production of antibodies (in case of myeloma known as paraprotein) - they can build up in kidney
Also there is less room for other blood cells to grow in bone marrow, so can get pancytopenia

Question 22

Myeoloma - features

Answer 22

• Anaemia
• Pancytopenia
• Median age at diagnosis 66
• Bone problems: lytic bone lesions, pathological fractures (paraplegia), hypercalcaemia
• Monoclonal paraprotein (IgG or IgA or free light chain)
• Hyperviscosity of blood can lead to clots
• Cx: Renal Failure

Treatment
Induction with combination chemotherapy
Autologous stem-cell transplant in first remission
bone disease –> biphosphonates, analgesia

Question 23

What are Bence Jones proteins?

Answer 23

Bence Jones proteins are found in the urine and particularly diagnostic of multiple myeloma in the context of target organ manifestations such as renal failure, lytic (or “punched out”) bone lesions, anemia, or large numbers of plasma cells in the bone marrow of patients.

The proteins are immunoglobulin light chains (paraproteins) and produced by neoplastic plasma cells

Dx: serum/urine electrophoresis - diagnostic test for MM

Question 24

Lymphoma - definition and types

Answer 24

Neoplastic disease of mature lymphocytes in lymphoid tissues (lymph nodes, gut, tonsils, skin etc)
- commonly a solid tumour all in one place

1. Hodgkin Lymphoma
   - classical HL
   - nodular lymphocyte predominant (NLPHL)
2. Non-Hodgkin Lymphoma
   - B cell (low or high grade)
   - T cell (systemic or cutaneous)

Question 25

Classical Hodgkin Lymphoma

Answer 25

- Most present with painless painless cervical and/or supraclavicular lymphadenopathy - 2 peaks of incidence (15-30, >65) - Lymphopenia and anaemia are often present in advanced disease - Pruritus and intermittent fevers are often associated with night sweats (B symptoms) - The anaemia is an anaemia of chronic disease

Question 26

Lymphoma - investigations (general)

Answer 26

- FBC, LFTs, LDH (lactate), U+Es - blood smear - Biopsy of nodes (shows type and grade of lymphoma) - bone marrow biopsy (staging) - CT neck/chest/abdomen/pelvis - Serum Ig - HIV serology (HIV can be a/w lymphoma) - PET-CT (increased uptake at involved sites) - FISH – cytogenetics study (can show chromosomal translocations in follicular, mantle cell and burkitt lymphoma)

Question 27

B cell Lymphoma - low vs high grade

Answer 27

Low Grade - Most patients are >50 - presentation in advanced-stage disease is with painless widespread low-volume lymphadenopathy - Splenomegaly is common in advanced-stage High Grade - Affects all ages - Usually present with systemic symptoms (B symptoms) and large masses/features of organ infiltration

Question 28

Lymphoma - treatment (general)

Answer 28

- HL and high grade NHL: Combination chemotherapy +/- radiotherapy - Low grade NHL: Radiotherapy to lymph nodes (regional radiotherapy) - Analgesia - Other option is to offer rituximab alone or combined with a chemo drug or prednisolone - consider antimicrobial prophylaxis if severely neutropenic and CNS prophylaxis if HIV-associated

Question 29

T Cell lymphoma -features

Answer 29

- less common type and worse prognosis than B cell Acute = fatigue, skin rash and enlarged lymph nodes in the neck, armpit and groin, +/- hypercalcaemia which can cause confusion, bone pain and severe constipation Chronic = slow growing and frequently characterised by enlarged lymph nodes that can be found anywhere in the body. Skin rash and fatigue are also common - cutaneous type tends to be indolent

Question 30

Stem cell transplant types

Answer 30

1. Autologous – from patient’s own stem cells Allows delivery of very high doses of chemotherapy Can be curative (e.g. relapsed Hodgkin lymphoma) or to extend remission (e.g. myeloma) 2. Allogeneic From a donor (sibling or unrelated donor) Done always with curative intent (all types of haematological malignancy, but most commonly in acute leukaemia)