Lymphoid neoplasms with plasmablastic differentiation were classified by the

World Health Organization The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level o ...

, 2017 as a sub-grouping of several distinct but rare lymphomas in which the malignant cells are

B-cell B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted ...

lymphocytes that have become plasmablasts, i.e. immature plasma cells. Normally,

s take up foreign antigens, move to the

germinal center Germinal centers or germinal centres (GCs) are transiently formed structures within B cell zone (follicles) in secondary lymphoid organs – lymph nodes, ileal Peyer's patches, and the spleen – where mature B cells are activated, prolife ...

s of secondary

lymphoid organs The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system, and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphatic or lymphoid o ...

such the

spleen The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes .

and

lymph node A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that inc ...

s, and at these sites are stimulated by

T-cell A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell ...

lymphocytes to differentiate (i.e. change their cell type) into plasmablasts and thereafter mature plasma cells. Plasmablasts, and to a greater extent, plasma cells make and secrete antibodies that bind the antigens to which their predecessor B-cells were previously exposed (see plasma cell differentiation). Antibodies function, in part, to neutralize harmful bacteria and viruses by binding antigens that are exposed on their surfaces. Due to their malignant nature, however, the plasmablasts in lymphoid neoplasms with plasmablastic differentiation do not mature into plasma cells or form antibodies but rather uncontrollably proliferate in and damage various tissues and organs. The individual lymphomas in this sub-group of

malignancies Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

have heterogeneous clinical, morphological, and gene findings that often overlap with other members of the sub-group. In consequence, correctly diagnosing these lymphomas has been challenging. Nonetheless, it is particularly important to diagnose them correctly because they often have very different prognoses and treatments. The lymphoid neoplasms with plasmacytic differentiation are: * 1) Plasmablastic lymphoma: The most common of these lymphoid neoplasms. * 2) Plasmablastic plasma cell lymphoma or plasmablastic plasmacytoma: A lymphoid neoplasm that disseminates widely like the plasma cell lesions in

multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, ane ...

or is localized like the plasma cell lesions in

plasmacytoma Plasmacytoma is a plasma cell dyscrasia in which a plasma cell tumour grows within soft tissue or within the axial skeleton. The International Myeloma Working Group lists three types: solitary plasmacytoma of bone (SPB); extramedullary plasmacy ...

. * 3) Primary effusion lymphoma, human herpes virus-positive: Also termed primary effusion lymphoma, type I; it is usually characterized by manifesting

effusion In physics and chemistry, effusion is the process in which a gas escapes from a container through a hole of diameter considerably smaller than the mean free path of the molecules. Such a hole is often described as a ''pinhole'' and the escape ...

s in body cavities. * 4) Primary effusion lymphoma, human herpes virus-negative: Also termed primary effusion lymphoma, type II; it is characterized by having effusions in body cavities. * 5) Anaplastic lymphoma kinase-positive large B-cell lymphoma: An

anaplastic large cell lymphoma Anaplastic large cell lymphoma (ALCL) refers to a group of non-Hodgkin lymphomas in which aberrant T cells proliferate uncontrollably. Considered as a single entity, ALCL is the most common type of peripheral lymphoma and represents ~10% of all per ...

in which the malignant cells have plasmablastic features and a distinguishing

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, m ...

in the ''

anaplastic lymphoma kinase Anaplastic lymphoma kinase (ALK) also known as ALK tyrosine kinase receptor or CD246 (cluster of differentiation 246) is an enzyme that in humans is encoded by the ''ALK'' gene. Identification Anaplastic lymphoma kinase (ALK) was originally dis ...

'' gene. * 6) Human herpesvirus 8-positive diffuse large B-cell lymphoma, not otherwise specified: This lymphoid neoplasm usually arises from the lymphoproliferative disease,

idiopathic An idiopathic disease is any disease with an unknown cause or mechanism of apparent spontaneous origin. From Greek ἴδιος ''idios'' "one's own" and πάθος ''pathos'' "suffering", ''idiopathy'' means approximately "a disease of its own kind ...

multicentric Castleman disease. Except for human herpesvirus 8-positive diffuse large B-cell lymphoma, not otherwise specified, these lymphoid neoplasms are often associated with Epstein-Barr virus infection of the malignant plasmablastic cells. In cases so infected, the lymphoid neoplasm may result, at least in part, from this viral infection and therefore can be considered as examples of the Epstein-Barr virus-associated lymphoproliferative diseases.

References

{{Reflist Lymphoma Non-Hodgkin lymphoma Epstein–Barr virus–associated diseases Infectious causes of cancer