CD79A

So, Burkitt is a mature B cell.

So, it expresses CD19, CD20, CD22, and CD79A.

As second Nick has told us, it's germinal center.

So, it should be CD10 and BCL6 positive.

Remember we talked about the germinal center and the different types of cells that hang out in there.

When we're working up a DLBCL, first we prove it's a B cell, and so that should mean that it expresses CD20, CD22, CD79A, PAX5, surface immunoglobulin, or light chains in some cases.

DLBCL is unfortunately a lot more variable than some of the indolent lymphomas in its surface marker expression because it can come from a variety of locations in the maturation cycle.

it would be nice to know exactly where in the maturation cycle that any given DLBCL came from, because this might tell us how it's going to behave.

To diagnose it, get a core or excisional biopsy, please no FNA, as the architecture is essential for diagnosis.

Send fresh tissue for flow cytometry and formalin-fixed tissue for histopathology, and avoid steroids before biopsy if possible.

Diagnosis should include the usual B-cell markers of CD20, CD79A and PAX5.

The HANDS algorithm by IHC for CD10, BCL6 and MUM1 is a surrogate that splits DOBCL into GCB versus non-GCB subtypes with about 80% accuracy.

So if you can find clonality, that goes a long way to proving a malignant population is present.

In these cases, the immunophenotype of Hispanic marginal zone lymphoma is positivity for B-cell markers, so CD19, CD20, CD22, CD79A, and surface immunoglobulin with light chain restriction showing clonality.

They are negative for CD5, CD10, CD103, CD25, and usually negative or dim CD200 and CD23.

that's probably all that needs to be said about splenic marginal zone lymphoma.