What is CD20 positive B cell lymphoma?

A protein found on B cells (a type of white blood cell). It may be found in higher than normal amounts in patients with certain types of B-cell lymphomas and leukemias. Measuring the amount of CD20 on blood cells may help to diagnose cancer or plan cancer treatment.

Is marginal zone lymphoma CD20 positive?

Marginal zone lymphoma (MZL) consists of 3 different subtypes that are all CD19-positive, CD20-positive, CD22-positive, CD5-negative, CD23-negative, and cyclin D1–negative. Combining clinical and pathologic data is necessary to make a diagnosis.

How is Plasmablastic lymphoma diagnosed?

An initial diagnosis of PBL was made with a differential diagnosis of plasmablastic plasmacytoma/myeloma for confirmation by tissue biopsy and other workup due to overlap and similarities between both diseases and other diseases as well as diffuse large B-cell lymphoma (DLBCL) with plasmacytic differentiation.

What percentage of B cells have CD20?

Approximately 25% of B-cell lymphoma patients have the CD20 expression below the cut-off value showing that the low CD20 expression might be more common than presumed from our previous study.

What is a low grade B cell lymphoma?

Low-grade B-cell lymphomas of MALT type may arise in or secondarily involve the skin and subcutaneous tissue and have a tendency to affect middle-aged to older women. These tumors are characterized by multiple extranodal relapses and are associated with long patient survival.

Is marginal zone lymphoma Hodgkin’s or non Hodgkins?

Marginal zone lymphoma (MZL) is the second most common indolent non-Hodgkin’s lymphoma (iNHL).

What type of lymphoma is plasmablastic?

Introduction. Plasmablastic lymphoma (PBL) is a clinicopathological entity that was initially described in 19971 and is now considered a distinct subtype of diffuse large B-cell lymphoma (DLBCL) seen more commonly in patients with HIV infection.

What does anti CD20 mean?

Anti-CD20 monoclonal antibodies (mAbs) are used to achieve B cell depletion, and were initially developed to treat B cell proliferative disorders, including non-Hodgkin’s lymphoma (NHL) and chronic lymphocytic leukemia (CLL).

What is a CD20 negative B cell lymphoma?

Almost all B cell NHLs are positive for CD20. CD20- negative NHLs are rare with a rate of 1–2% of all B cell NHLs [20]. The most common types of these include plasmablastic lymphoma, primary effusion lymphoma, large B-cell lymphoma arising from HHV8-associated multicentric Castleman’s disease, and ALK+ large B cell lymphoma [20, 21].

What is the pathophysiology of malignant plasmablasts of B-cell lymphoma?

The malignant plasmablasts in more than half the cases of PBL are infected with a potentially cancer-causing virus, Epstein Barr virus (EBV), and rare cases of PBL appear due to the plasmablastic transformation of a preexisting low-grade B-cell lymphoma.

What are the plasmablastic cells in anaplastic lymphoma kinase-positive large B-cell lymphoma?

Unlike PBL, the plasmablastic cells in anaplastic lymphoma kinase-positive large B-cell lymphoma strongly express the product of the ACVRL1 gene, i.e. activin receptor-like kinase 1 (ALK1) and are not infected with EBV and therefore do not express this virus’s EBER or BART RNAs.

What is the prognosis of ALK+ DLBCL with CD20 positive lymphoma?

Unlike the common DLBCL, ALK+ DLBCL is usually positive for CD38, CD138, and negative for CD20, CD30, and CD79a [ 28 ]. This type of lymphoma has a median survival of 20 months. In addition to the above rare CD20 negative lymphomas, CD20 positive lymphoma can relapse as CD20 negative lymphoma after CD20 antibody therapy [ 29 ].