Follicular Lymphoma Flashcards
Give an overivew of follicular lymphoma
This is a low grade b cell lymphoma and it occurs throughout adult life. It has a similar incidence in men and women and it arises in the germinal centre (follicle centre) B cell
Describe the normal histology of a lymph node
There is the follicle centre, the mantle zone and then the marginal zone, each of these zones can derive certain lymphomas: follicular lymphoma, mantle cell lymphoma an marginal zone lymphoma
Describe the epidemiology of follicular lymphoma
It is the second most common lymphoma after diffuse large b-cell lymphoma. It comprises 20-25% of all new lymphoma.
It is more common in the west than in asian populations
Desrcibe the aetiology of follicular lymphoma
Not much is known about it
2-3-% are related to EBV
Describe the clinical features of FL
localised/generalised lymphadenopathy
can also cause splenomegaly
often widespread at diagnosis so bone marrow infiltration is common
How is follicular lymphoma diagnosed?
It is diagnosed with lymph node biopsy
or by cytological, immunophenotypic, cytogenetic and molecular genetic features of circulating lymphoma cells
What is seen on the lymph node biopsy?
Follicular growth pattern
What is the immunophenotype of follicular lymphoma?
CD10+, CD19+, CD20+, CD22+, CD45+, CD79a, CD79b and FMC7, k/l clonal excess
CD3-, CD5-, CD15-, CD30-, CD23-
Describe the appearance of the blood film for follicular lymphoma morphology
Cleft cells are visible
What is seen on trephine biopsy of FL?
Paratrabecular infiltration
What are the cytogenetic findings of FL?
One of three chromosomal rearrangements that bring BCL2 under the influence of the enhancer of an immunoglobulin gene
common aberrations:
t(14;18)(q32.33;q21.33) IGH locus
t(2;18)(p11.2;q21.33) iGK
t(18;22)(q21.33;q11.22) IGL
What tests are used to diagnosis molecular origins?
FISH
PCR
RT-PCR
RQ-PCR - MRD
What is the BCL2 gene responsible for?
It encodes an anti-apoptotic protein, this stabilises the mitochondrial membrane and prevents efflux of cytochrome c and subsequent activation of caspases in response to DNA damage - this is the intrinsic pathway of induction of apoptosis
Follicular lymphoma calls are resistant to apoptosis and it is postulated that they survive when growth signals are withdrawn whereas normal b lymphocytes would undergo apoptosis
Describe the staging of lymphoma
Stage 1: Presence of one lymph node
Stage 2: Two or more lymph nodes on one side of the diaphram - can also be a lymph tissue
Stage 3: Two or more lympph nodes or tissue on either side of the diaphragm
Stage 4: Disease of non lymphoid organs too
A - absence of B symptoms
B - presence of B symptoms
What are the treatment possibilities for follicular lymphoma?
Field radiotherapy
Chemotherapy - combination chemotherapy or bendamustine
Immunotherapy anti CD20
Chemo-immunotherapy
Immune modulators- lenalidomide
Ibrutinib or idelalisib - these induce apoptosis by blocking signalling
More intensive treatment:
Radiotherapy
Intensive chemotherapy and autologous SCT
Allogeneic stem cell transplant
The optimal initial treatment is considered to be comination chemo plus rituximab
