Revision - Lymphoma Flashcards
What is one of the key features which distinguish most lymphomas from leukaemia?
What are the exceptions to this rule?
The malignant cells are MATURE lymphocytes, and they arise within sites OUTSIDE of the bone marrow (e.g. lymph nodes).
In contrast, leukaemia develops from immature blasts and arises within the bone marrow.
Exception –> lymphoblastic lymphomas (these develop from immature precursor lymphoblasts similarly to leukaemia).
How is lymphoblastic lymphomas distinguished from lymphoblastic leukaemia?
By the degree of bone marrow infiltration by blasts:
<25% bone marrow involvement –> lymphoma
> 25% –> leukaemia
What are lymphoblastic lymphomas treated the same as?
ALL
What are B symptoms?
1) Fever
2) Drenching night sweats
3) Weight loss >10% in 6m
What is Hodgkin’s lymphoma?
Uncontrolled proliferation of B lymphocytes.
Pathophysiology of Hodgkin lymphoma?
B lymphocytes mutate which leads to the presence of multi nucleated giant cells (‘Reed Sternberg’ cells) and large, mono-nucleated cells (malignant ‘Hodgkin’ cells).
What are the 2 main types of Hodgkin’s lymphoma?
1) Classical (95%)
2) Nodular lymphocyte-predominant HL (5%)
What 4 subtypes can classical HL be further divided into?
1) Nodular sclerosis
2) Mixed cellularity
3) Lymphocyte-rich
4) Lymphocyte-depleted
What is the most common type of classical HL?
Nodular sclerosis
What infection is implicated in around 40% of HL cases?
EBV
What are some risk factors for HL?
1) EBV infection
2) Immunosuppression e.g. organ transplant, immunosuppressant therapies
3) Autoimmune e.g. RA, SLE, sarcoidosis
4) FH (same-sex siblings of patients with Hodgkin’s lymphoma are 10x more likely to develop the condition)
5) HIV
6) Smoking
What is the distinctive histological feature in Hodgkin’s lymphoma?
Reed-Sternberg cells
Clinical features of Hodgkin’s lymphoma?
1) Lymphadenopathy
2) 2) B symptoms:
- fever >38
- night sweats
- unintentional weight loss of >10% over 6 months
3) Pel-Ebstein fever
4) Abdo pain (if abdominal lymphadenopathy is involved)
5) Pruritus
6) Clinical hepato/splenomegaly (rare)
7) Bone marrow involvement (5-8%)
What lymph nodes are typically involved in HL?
(3)
1) Cervical
2) Supraclavicular
3) Mediastinal
What is Pel-Ebstein fever?
A cyclical fever followed by periods of being afebrile for 1-2 weeks (rare)
What are the NICE referral guidelines for Hodgkin’s lymphoma in adults?
2ww referral for any unexplained lymphadenopathy
What are the NICE referral guidelines for Hodgkin’s lymphoma in children and young people?
Consider a very urgent referral (<48 hours) for specialist assessment for Hodgkin’s lymphoma in children and young people presenting with unexplained lymphadenopathy.
Timeline of referral for unexplained lymphadenopathy in adults vs children & young adults?
Adults -> 2ww
Children & young adults -> <48h
What is the investigation for definitive diagnosis of HL?
Lymph node excision biopsy
What does a lymph node excision biopsy reveal in HL?
Reed-Sternberg cells (owl’s eye appearance)
Is HL or non-HL more common?
Non-HL
Which type of lymphoma is most associated with EBV?
HL
What is the mainstay of treatment for HL?
Chemo +/- radiotherapy
What staging system is used for HL?
Ann Arbor staging
Describe stage I to IV of the Ann Arbor staging system
I - Involvement of one lymph-node region or lymphoid structure (e.g. spleen or thymus).
II - Two or more lymph node regions on the same side of the diaphragm.
III - Lymph nodes on both sides of the diaphragm.
IV - Involvement of extranodal site(s).
Due to the increased risk of opportunistic infections following chemotherapy in lymphoma, what vaccines are patients offered?
1) Polyvalent pneumococcal vaccine
2) Influenza
3) Meningococcal group C conjugate vaccine
4) Haemophilus influenzae type b vaccine
Regardless of stage, what is relapsed HL treated with?
High dose chemo followed by autologous stem cell transplant (ASCT).
If a transfusion of blood products is required in HL, what products must patients receive?
irradiated blood products only –> to reduce the risk of transfusion-associated graft-versus-host disease.
What is the most immediate and common complication arising from chemotherapy in HL?
Myelosuppression –> anaemia, thrombocytopenia, and neutropenia,
Why can HL treatment cause cardiotoxicity?
Due to anthracycline-based regimens
What 2ary cancers are long-term survivors of Hodgkin’s lymphoma at a significantly elevated risk of developing?
1) AML
2) Non-Hodgkin lymphomas
3) Solid tumours including breast and lung cancer
Is non-HL more common in boys or girls?
Boys
What are the majority of types of non-HL?
Of B-cell origin (e.g. Burkitt’s lymphoma)
What is Burkitt’s lymphoma?
A type of non-HL (of B-cell origin)
What is the main treatment for non-HL?
chemo
What is seen on microscopy in Burkitt’s lymphoma?
‘starry sky’ appearance: lymphocyte sheets interspersed with macrophages containing dead apoptotic tumour cells
What are the 2 types of Non-Hodgkin lymphoma?
1) B cell (more common)
2) T cell
What do the neoplasic B cells in B cell lymphoma typically express on their surface?
CD20
What are the 3 types of B cell lymphoma?
1) Diffuse large cell (most common)
2) Follicular lymphoma
3) Burkitt lymphoma
What translocation may be seen in follicular lymphoma?
Between 14 and 18
How aggressive is Burkitt lymphoma?
Highly aggressive
Does alcohol cause painful lymph nodes in Hodgkin or Non-Hodgkin lymphoma?
Hodgkin lymphoma
What infection can Burkitt lymphoma be associated with?
EBV
How does Burkitt lymphoma typically present in Africa?
Extranodal involvement of jaw
How does Burkitt lymphoma typically present outside Africa?
Extranodal involvement of the abdomen (ileocaecal junction)
Appearance of Burkitt lymphoma under a microscope?
Starry sky
Mx of non-HL?
Chemo & radiation
What medication can be used if CD20+ B cells are present in non-HL?
Rituximab (binds CD20 - causes lysis & apoptosis)
What do B cells differentiate into?
Plasma cells (these release antibodies)
What infections can Hodgkin lymphoma be associated with? (2)
1) HIV
2) EBV
Does HL or non-HL typically involve extranodal sites (e.g. skin, GI tract, brain)?
Non-HL
Hodgkin vs Reed-Sternberg cells?
Hodgkin: large, mononuclear
Reed-Sternberg: multinucleated
What are the 2 subtypes of HL?
1) Classical HL (most common)
2) Nodular lymphocyte predominant HL
What are the 4 subtypes of classical HL?
1) Nodular sclerosis (most common)
2) Mixed cellularity
3) Lymphocyte-rich (best prognosis)
4) Lymphocyte-depleted
What is the most common type of HL?
Classical
What is the most common type of classical HL?
Nodular sclerosis
