1: Mature B-Cell Neoplasms
Current WHO standards group a large group of B Cell neoplasms, including many non-Hodgkin's lymphomas, some leukaemias and myeloma under this heading. Their unifying feature is the resemblance of tumour cells to a type of mature B Cell. This resemblance is the basis of subclassification into the well known diffuse large B Cell, follicular, mantle cell and marginal zone lymphomas.
A summary of the epidemiology is given below:
Type | Age | Gender | Geography | Incidence |
---|---|---|---|---|
DLBCL | 60 | Slightly more men | N/A | Most common lymphoma |
Follicular | 50-60 | 70% women | High in West Less in Developing |
20% of all lymphoma |
Burkitt | Children & Young Adults | |||
Mantle Cell | ||||
Marginal Zone | ||||
Myeloma | 65-70 | More men | African descent | 3rd most common lymphoma |
CLL | 60 | 2:1 | Higher in West | Most common adult leukaemia |
A summary of the microscopic appearances is presented below:
Type | Architecture | Cell Size | Cytoplasm | Nucleus |
---|---|---|---|---|
DLBCL | Sheets of cells, no nodularity | Intermediate to large | Eosinophilic | Vesicular |
Follicular | Closely packed follicles Diffuse in high grade cases |
Centrocytes: Small Centroblasts: Intermediate |
Minimal Moderate |
Cleaved nucleus Vesicular, nucleoli |
Burkitt | Diffuse, "Starry Sky" | Intermediate | ||
Mantle Cell | Follicular | Small | Minimal | Cleaved nucleus |
Marginal Zone | ||||
Myeloma | Diffuse | Normal | Perinuclear clearing | Eccentric |
CLL | Diffuse | Small | Scant | Slightly irregular |
A summary of immunohistochemical appearances:
- CD19, CD20 and CD79a are present in almost all B cell lymphomas
- The remaining CD markers are used for distinguishing between certain types.
- CD5 and CD23 are present in mature B cells (CLL)
- marker
Type | CD79a | CD20 | CD19 | CD5 | CD10 | CD15 | CD23 | CD30 | CD34 | Cyclin D1 | Ig | BCL2 | BCL6 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
DLBCL | + | + | +/- | ||||||||||
Follicular | + | + | + | - | + | - | - | - | - | - | + | + | + |
Burkitt | |||||||||||||
Mantle Cell | + | + | + | + | - | - | - | - | - | + | + | ||
Marginal Zone | |||||||||||||
Myeloma | |||||||||||||
CLL | + | + | + | + | - | - | + | - | - | - | + | - | - |
A summary of common chromosomal changes:
Type | Translocations | Other findings |
---|---|---|
DLBCL | ||
Follicular | BCL2/IGH t(14;18) |
|
Burkitt | cMYC/IGH t(8;14) |
|
Mantle Cell | Cyclin D1/IGH t(11;14) |
|
Marginal Zone | MALT/BCL10 t(14;18), t(11;18), t(1;14) |
|
Myeloma | ||
CLL | Rare | Nil |
Mature B Cell Neoplasms
- a) Diffuse Large B Cell Lymphoma (DLBCL)
- b) Follicular Lymphoma
- c) Burkitt Lymphoma
- d) Mantle Cell Lymphoma
- e) Marginal Zone Lymphoma
- f) Plasma Cell Neoplasms
- g) Mature B Cell Leukaemia