Haematological malignancies Flashcards
What is cell culture?
Procedure used to grow cells under controlled conditions
What is cell harvest?
Procedure used to collect cells from the specimen
Of FISH and karyotype which is the specific and which is the global test?
FISH = specific Karyotype = global
Which test has a higher sensitivity FISH or karyotype?
FISH
Which test can be performed more quickly FISH or karyotype?
FISH
Do you require metaphase or interphase for karyotype?
Metaphase spreads
Do you require metaphase or interphase for FISH?
Can be performed on both
What are the two cell lineages that can arise from haematopoeitic stem cells?
Myeloid and lymphoid
Examples of cells in the myeloid lineage
Anything that’s not T cells, B cells or NK cells e.g. platelets, red blood cells (erythrocytes), granulocytes, basophills etc.
Three reasons why we test for haematological malignancies?
Diagnosis
Prognosis
Monitoring
Prognosis of complex karyotypes?
Bad
Prognosis of balanced translocation?
Good
In which haematological malignancies can BCR-ABL1 be found?
Most common in CML
ALL
AML
What are blast cells?
Immature cells in either the myeloid or lymphoid lineage e.g. a myeloid blast can become all the myeloid cells but not lymphoid ones
In leukaemias why is bone marrow a better choice of starting material than blood?
Because bone marrow will have more immature white blood cells than blood (in normal individuals blood shouldn’t contain immature white cells but in affected individuals it will)
What is leukaemia?
Cancer of white blood cells where changes occur in the bone marrow
Symptoms of leukaemia?
Fatigue, easy bruising, proneness to infection
What does acute mean?
Occurs quickly
What does chronic mean?
Occurs over a long period of time
Different types of leukaemia?
AML (acute myeloid leukaemia)
ALL (acute lymphoblastic leukaemia)
CML (chronic myeloid leukaemia)
CLL (chronic lymphocytic leukaemia)
What is more aggressive “lymphoblastic” or “lymphocytic”
Lymphoblastic because these blast cells are less differentiated and therefore more aggressive
What is more aggressive ALL or CLL?
ALL
What cells are overproduced in AML??
Myeloid cells
Standard rearrangements in AML
t(15;17) PML;RARA
t(8;21) RUNX1T1;RUNX1
inv(16) CBFB-MYH11
All make chimeric fusion proteins
t(15;17) is characteristic of what?
APML - acute promyelocytic leukaemia
What treatment is APML sensitive to?
Retinoic acid and arsenic
Are APML and APL the same thing?
Yes
How are rearrangements in AML identified?
Can use karyotype, FISH, RT-PCR or multiplex PCR
If you have a suspected APML what analysis method would you use for a rapid analysis?
FISH or RT-PCR - can get result very quickly
If you have suspected AMPL should rapid analysis be performed?
Yes
If you have a cytogenetically normal AML what test could you use to look for mutations in FLT3 and NPM1?
Multiplex PCR - amplify up and look at size on gene marker. Controls run alongside with known size that these fragments should be
Prognosis of t(15;17) PML;RARA in AML
Favourable
Prognosis of t(8;21) RUNX1T1;RUNX1 in AML
Favourable
Prognosis of inv(16) CBFB-MYH11 in AML
Favourable
Prognosis of FLT3 internal tandem duplications in AML
Poor prognosis
Prognosis of NPM1 mutations in AML
Favourable
What would you use multiple PCR for in AML
To look for mutations in NPM1 and FLT3 if was cytogenetically normal
Why is APML worse than AML?
APML tend to have serious bleeding abnormalities due to low platelet count and clotting factors - at increased risk of bleeding in their brain
What is myelodysplastic syndrome (MDS)?
Affects the production of myeloid cells, causing cytopenias (reduction in mature blood cell)
How does MDS progress?
Can progress slowly but can rapidly convert into AML
Loss of Y or 15+ is problematic why?
Often occurs in elderly people with no haematological disease but may also be markers of neoplastic myeloid clones (MDS/AML)
What is CML?
Myeloproliferative neoplasm (MPN)
What cells are overproduced in CML?
Myeloid cells
CML is well managed in what phase?
Chronic phase
What are the three phases of CML?
Chronic
Aggressive
Blast
What happens when CML switches into “blast crisis”?
It resembles acute leukaemia which is difficult to treat
Testing available for CML diagnosis
Karyotype
FISH
RT-PCR
Translocation found in almost all cases of CML
t(9;22)(q34;q11) on derivative 22 (Philadelphia chromosome)
Does t(9;22) in CML create a chimeric fusion protein?
Yes, BCR-ABL1. This has enhanced tyrosine kinase activity resulting in increased proliferation
Drug treatment that can be used in individuals with Ph+ CML
Imatinib (TKI)
In terms of monitoring what haematological malignancies can we monitor for?
Can do for all, but in Glasgow only do for CML (two transcripts) all other monitoring is sent down south
Does “blast crisis” in CML have a high mortality rate?
Yes
When does “blast crisis” occur in CML
When >30% of cells in blood/bone marrow are immature blood cells (blast cells)
When is MRD done?
When the patient is in remission
When is monitoring done?
At certain time periods after the patient has received a diagnosis and while they are receiving treatment
How is monitoring performed for CML?
RT-PCR to determine transcript and then QRT-PCR to determine level
Imatinib resistance can be primary or secondary, explain
Primary - failure to achieve a response
Secondary - acquired resistance
What are the three myeloid disease categories?
MDS
MPN
Myeloid leukaemia
Examples of myeloproliferative neoplasms
CML
Polycythaemia vera
essential thrombocythaemia
Genes mutations generally seen in MPN
JAK2, CALR, MPL
What cells are overproduced in ALL
Lymphoid cells
What age group is ALL mostly seen in
Young children
Is ALL generally a T-cell proliferation or a B-cell
B-cell
Translocation seen in 25% of ALL cases
t(12;21) ETV6;RUNX1
What is the prognosis for t(12;21) in ALL
Favourable
In ALL if children are diagnosed early whats the cure rate
Above 90%, if diagnosed early respond well
Is BCR-ABL found in ALL?
Yes, found in adults (11-30%) and in children (2-4%) has a poor prognosis in both
Does ALL have a high mortality rate in adults?
Yes
Poor prognosis abnormalities in ALL children
iAMP21 t(17;19) MLL translocations low hypodiploidy t(9;22)
Poor prognosis abnormalities in ALL adults
iAMP21
MLL translocations
low hypodiploidy
t(9;22)
What cells are overproduced in CLL
Lymphoid cells (generally B)
Does CLL affect old or young
Most common in old
How does CLL progress?
1/3 regress, 1/3 don’t progress and 1/3 progress to acute leukaemia
Good prognostic abnormality in CLL
-13q4
Intermediate prognostic abnormality in CLL
Trisomy 12
Poor prognostic abnormalities in CLL
-17p (or mutation of TP53)
Deletion of segment of ATM (chr11)
What is lymphoma?
Cancer of white blood cells where changes occur in the lymph nodes and other lymphoid tissues (spleen, GALT)
Symptoms of lymphoma
Lumps, night sweats, fever
If individuals said to have a Ph+ variant translocation in CML what does this mean
They have a translocation involving chromosomes 9;22 and other chromosome(s)
What percentage of individuals with CML have a Ph+ variant translocation
5-10%
What referrals come from haematology?
Leaukaemias and myelomas
What do haematology base their ?diagnosis on?
Patient demographics
Symptoms
Full blood count
What cells look like on blood film
Is FLT3 a good marker for monitoring of AML?
No because it can disappear when patient is in remission
What are good markers for AML monitoring?
NPM1 and the fusions
What leukaemias are classed as urgent referrals?
Diagnostic acute leukaemia and CML
What is the time frame for urgent diagnostic acute leukaemia and CML results to go out
14 calendar days - could do rapid test by FISH/PCR in three working days and then karyotype within the 14
Routine referrals for the leukaemias turn around time
21 days
What is myeloma?
When changes occur in activated plasma cells (B-cells that make antibody)
Symptoms of myeloma?
Bone fractures, kidney injury
What is the commonest haematological malignancy?
Myeloma
Is myeloma curable?
It is treatable but not curable
Genetic testing offered for myeloma
FISH
Genetic testing offered for lymphoma
FISH
Sometimes B/T cell clonality
Starting material for leukaemia
Preferably bone marrow but can use blood
Starting material for lymphoma
FFPE FISH slides
Starting material for myeloma
Preferably bone marrow but can use blood
Where do referrals for lymphoma come from?
Pathology
Where do referrals for myeloma come from?
Haematology
Where do referrals for leukaemia come from?
Haematology
Poor prognosis karyotypes in myeloma
t(4;14)
-13q
t(11;14)
Deletion of TP53
When do we offer chimerism testing?
For leukaemia bone marrow transplantation patients
What is a chimera?
A single organism composed of cells with distinct genotypes
When are bone marrow transplantation’s carried on in individuals with leukaemia
When other treatments have failed
If have very poor prognosis
In kids with ALL
What does chimerism testing monitor?
Engraftment
What does 100% chimerism mean?
No recipient cells can be found
How is chimerism testing performed?
Chemo to get rid of malignant cells, QF-PCR to look at microsatellites from donor and recipient to see if recipient cells have engrafted in donor
What can you do if leukaemia returns after transplant?
Give T cells from donor which attack leukaemia cells
What is MYC and where is it located?
Proto-oncogene, chromosome 8, role in cell cycle progression and apoptosis
What type of haematological malignancy is MYC generally mutated in?
Lymphoma
Different types of FISH probes available and what they detect?
Enumeration probes (copy number) Break apart probe (gene rearrangement) Dual fusion (specific translocations)
Why do we try and diagnose type of lymphoma someone has?
Different types are treated differently depending on how aggressive they are.
Different classes of lymphoma
Hodgkins and Non-Hodgkins lymphoma
Difference between Hodgkins and Non-Hodgkins lymphoma
Hodgkins always have Reed Sternberg cells (B lymphocytes), while Non-Hodgkins can be B or T cell
Characteristics of Burkitt lymphoma
highly aggressive B cell lymphoma, fast growing and high grade, rare. Most common abnormality t(8;14) MYC;IGH
Characteristics of Follicular lymphoma
2nd most common NHL, B cell, most common abnormality t(14;18) IGH;BCL2. Sometimes IGH;BCL6
What is the most common type of NHL
Diffuse large B cell (aggressive), no specific abnormality associated
Most common BCR-ABL1 transcripts
e13a2 and e14a2 (MAJOR transcripts) produce 210kDa protein and e1a2 (MINOR transcript) produce 190kDa protein
Most common BCR-ABL1 transcript in CML
Ones that produce 210kDa protein
Most common BCR-ABL1 transcript in ALL
One that prodcues 190kDa protein
What mitogen can be used to stimulate B cells
PMA
What mitogen can be used to stimulate T cells
PHA
Do clinicians prefer ISCN or words
They prefer words describing how many chromosomes youve got
What does hypodiploid mean?
35-46 chromosomes
What does hyperdiploid mean?
47-57 chromosomes
What does pseudodiploid mean?
46 chromosomes (abnormal)
What does near triploid mean?
Number close to 69 (3n)
In ISCN what is // used for
To represent a chimera - separate cells from host and donor
In ISCN what is [*] used for
To detail the number of cells in that cell line
In ISCN are normal cells presented at beginning or end?
End
Three different types of karyotype
Normal
Abnormal
Complex
Categories of acquired genetic disease
Formation of chimeric fusion protein
Gain or amplification of gene or gene product
Deletion/loss of function of a gene
If you see a +8 what do you think it is
A myeloid disorder (MDS or AML)
What is the tumour suppressor affected in retinoblastoma
RB1
Deletion of chromosome 5 is common in what type of disease?
MDS
What is the percentage for no response in monitoring?
96-100%
What is the percentage for minimal response in monitoring?
66-95%
What is the percentage for minor response in monitoring?
36-65%
What is the percentage for partial response in monitoring?
1-35%
What is the percentage for complete response in monitoring?
o%
For CML once found abnormality monitor using what kind of test
QRT-PCR (but they will send cytogenetic sample at intervals because you can get other abnormalities cropping up in Ph- cells)
Name some abnormalities in the poor prognosis risk group for AML
-5
-7
del(5q)
complex abnormality
In AML what is an abnormal karyotype defined as?
4 abnormalities or more
Is high hyperdiploidy a good or bad prognosis in ALL
Good
What is iAMP21
> 5 copies of RUNX1 = amp = iAMP21
Does pyrosequencing look at short or long fragments?
Short
If you have a sex mismatch donor and recipient for a bone marrow transplant what other testing could you do other than QF-PCR for microsatellite analysis
FISH for X/Y
Screening for those with BRCA1/2 mutation
Mamography or MRI
Screening for those with mutations in MMR genes/APC/MUTYH
Colonoscopy
Factors that increase risk of breast/ovarian cancer
Increasing age Higher body mass index Late menopause Pill Breast density
Ethical issues of testing someone for breast cancer
Issues regarding health insurance, employment
Confidentiality - will have to ask about other family members etc
If do have a mutation, concerns regarding child bearing issues
Down syndrome is a risk factor for what haematological malignancy?
Acute leukaemia
Environmental risk factors of cancer?
Radiation
Chemotherapy and radiotherapy
Epstein Barr Virus - Burkitt’s lymphoma
What is a major cytogenetic response in CML?
More than 65% Ph-ve
What is a complete cytogenetic response in CML?
100% Ph-ve
What FISH tests do we offer for myeloma?
TP53
IGH-FGFR3
IGH-MAF
CDKN2C
Do they use interphase or metaphase FISH for haematological specimens?
Both interphase and metaphase
Do specimens require culturing to get metaphases?
Yes
Do specimens require culturing to get interphases?
No, can get interphases from a straight harvest
For say ?BCR-ABL/PML-RARA samples what kind of FISH would be done on these fast turn around samples?
Interphase FISH because would get a straight harvest, no culturing
For haematological malignancies when would you use interphase FISH
If you were looking for a standard rearrangement for which probes were available/fast turn around
For haematological malignancies when would you use metaphase FISH
If you saw something unusual (say 3 way t) on a karyotype and you wanted to know location of it/needed help in working out breakpoints would do metaphase FISH
If you saw a marker chromosome what would you do?
If experienced staff have an idea what it is FISH for that chromosome. If hard to tell consider standard rearrangements for that diagnosis or ?. If have no idea just report as “marker1/2/3” in ISCN
Prognosis of unbalanced translocation
Depends on the level of imbalance
Why is ISCN important?
As an international standard it enables cytogeneticists across the world to understand the exact nature of the chromosome constitution in an individual
Sibling donors for bone marrow transplant - what considerations need to be taken in analysis of engraftment (QF-PCR of markers)
May struggle to get enough informative markers because siblings share 50% of genes
What % of donor cells need to be present for bone marrow transplant to have worked?
90%
If you see an abnormality on karyotype of an individual with ?leukaemia/myeloma, what do you need to consider about this abnormality
Is it clonal? Can you see it in almost every abnormal cell?
In which myeloproliferative neoplasm do you find JAK2 variants? And are these acquired or inherited?
Polycythemia vera, and they are acquired
Most common JAK2 variants in PV?
c.1849G>T, p.(Val617Phe) 90-95% cases
Variants in JAK2 exon 12 2-4% cases
How is JAK2 analysis performed?
Allele specific PCR for c.1849G>T variant and exon 12 deletion, followed by GeneMarker for analysis. For the deletion you get an extra peak 3 bp smaller than the WT and for the variant will get a peak in the “positive” bin
Are there sanger sequencing best practice guidelines available?
Yes
What is “improving outcomes guidance”?
Guidelines put in place by NICE, looks at haematological cancers and how we can use things like integrated reporting, MDTs, staffing levels and facilities to improve care for these patients
What does NICE stand for?
National Institute for Health and Care Excellence
What does NICE do?
Provides national guidance and advice to improve health and social care