2. Lymphomas Flashcards
Definition of lymphomas
Malignancies of the lymphoid system which primarily manifests themselves outside the bone marrow, at sites of normal lymphoid homing (lymph nodes, spleen, thymus, mucosa-associated lymphoid tissue)
Types of lymphomas
- Hodgkin Lymphoma
a. Classical
b. Non-classical - Non-Hodgkin Lymphoma
a. B-cell lymphoma
b. T-cell & NK cell lymphomas
How is each disease entity characterised and defined?
- Morphology (histological appearance)
- Immunophenotype (surface cellular markers)
- Molecular signature (characteristic translocations)
- Clinical features (presentation, clinical course)
Types of Non-Hodgkin Lymphoma
- B-cell Lymphoma
- Follicular lymphoma
- Diffuse large B-cell lymphoma
- Burkitt lymphoma
- Mantle cell lymphoma
- Marginal zone lymphoma: Splenic, extranodal & nodal
- Multiple myeloma
- B-cell acute lymphoblastic leukemia
- Chronic lymphocytic leukemia - T-cell & NK cell lymphoma
- Anaplastic large cell lymphoma
- Extranodal NK/T cell lymphoma
- Peripheral T cell lymphoma
- NOS T-cell acute lymphoblastic leukemia
What type of lymphomas constitute the majority?
B-cell lymphoma (85-90%)
How to classify Non-Hodgkin Lymphomas based on clinical course?
- Indolent lymphomas (small proliferation margin with low proliferation & low apoptosis rates)
margin,
a. Follicular lymphoma
b. Marginal zone lymphoma
c. Multiple myeloma
d. Anaplastic large cell lymphoma (cutaneous
CD30+ type) - Aggressive lymphomas (large proliferation margin
with high proliferation & high apoptosis rate)
a. Diffuse large B-cell lymphoma
b. Burkitt lymphoma
c. Mantle cell lymphoma
d. Anaplastic large cell lymphoma
e. All peripheral T cell lymphomas
Clinical presentations in Non-Hodgkin Lymphoma
- Enlarging masses at sites of lymphoid tissue
- Typically painless - Hollow organ compression/infiltration
- Pain, obstruction, perforation - Solid organ infiltration
- Renal insufficiency
- Hepatic insufficiency
- Bone marrow insufficiency - Systemic symptoms (B symptoms)
- Fever
- Night sweats
- Weight loss (> 10% body weight)
Clinical staging of Lymphomas (Ann Arbor Staging System)
- Stage I
- Single lymph node group or contiguous lymph nodes on same side of diaphragm
- 5-year survival = 90% - Stage II
- Two or more lymph node groups of lymphatic tissues on same side of diaphragm
- 5-year survival = 70% - Stage III
- Involvement of lymphatic tissues on both sides of diaphragm
- 5-year survival = 40% - Stage IV
- Involvement of extranodal sites (e.g. bone marrow, liver, lung, skin)
- 5-year survival = 20%
Definition of Hodgkin Lymphoma
Encompasses a group of lymphoid neoplasms characterized by the presence of neoplastic Reed-Sternberg cells amongst other differences from non-Hodgkin lymphomas; cell of origin is an altered B cell, hence technically rendering Hodgkin lymphomas as B cell lymphomas, but with a very different biology from other types of B cell lymphomas
Pattern of spread in Hodgkin Lymphoma
Orderly spread by anatomical contiguity
Pattern of spread in Non-Hodgkin Lymphoma
Non-contiguous spread
Distribution of nodes involved in Hodgkin Lymphoma
Often localized to a single axial group of nodes (cervical, mediastinal, para-aortic)
Distribution of nodes involved in Non-Hodgkin Lymphoma
Often involves multiple peripheral nodes
Nodes involved in Hodgkin Lymphoma
Mesenteric nodes & Waldeyer’s ring rarely involved
Nodes involved in Non-Hodgkin Lymphoma
Mesenteric nodes & Waldeyer’s ring commonly involved
Extranodal presentation in Hodgkin Lymphoma
Rarely
Extranodal presentation in Non-Hodgkin Lymphoma
Frequently
Types of Hodgkin Lymphoma
- Classical Hodgkin Lymphoma
a. 4 types:
- Nodular sclerosis
- Mixed cellularity
- Lymphocyte rich
- Lymphocyte depleted
b. Features:
- Classical Reed-Sternberg cells residing in a non-
neoplastic inflammatory background
- CD15+, CD30+
- Negative for other B cell markers & CD45
(leukocyte common antigen) - Non-Classical Hodgkin Lymphoma
a. 1 type:
- Nodular lymphocyte predominant
b. Features:
- Lymphocytic & histiocytic (L&H) variant cell (aka popcorn cell)
- CD20+, BCL6+
- CD15-, CD30-
Histology of Nodular sclerosis Hodgkin Lymphoma
- Bands of fibrosis
2. Lacunar variant RS cells in inflammatory background
Frequency of Nodular sclerosis Hodgkin Lymphoma
- 60%
- Female > Male
- EBV uncommon
5-yr survival for Nodular sclerosis Hodgkin Lymphoma
70%
Histology of Mixed cellularity Hodgkin Lymphoma
RS cells in inflammatory background (mixed)
Frequency of Mixed cellularity Hodgkin Lymphoma
- 30%
- Old > Young
- EBV in 70%
5-yr survival for Mixed cellularity Hodgkin Lymphoma
70%
Histology of Lymphocyte rich Hodgkin Lymphoma
RS cells in inflammatory background (many background lymphocytes)
Frequency of Lymphocyte rich Hodgkin Lymphoma
- 5%
2. EBV in 40%
5-yr survival for Lymphocyte rich Hodgkin Lymphoma
90%