World Library  
Flag as Inappropriate
Email this Article

Angioimmunoblastic T-cell lymphoma

Article Id: WHEBN0011107385
Reproduction Date:

Title: Angioimmunoblastic T-cell lymphoma  
Author: World Heritage Encyclopedia
Language: English
Subject: International Classification of Diseases for Oncology, Peripheral T-cell lymphoma
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Angioimmunoblastic T-cell lymphoma

Angioimmunoblastic T-cell lymphoma
Classification and external resources
ICD-10 ICD-O: 9705/3[1]
MeSH D007119

Angioimmunoblastic T-cell lymphoma (AITL, sometimes misspelled AILT) (also known as "Angioimmunoblastic lymphadenopathy with dysproteinemia"[2]:747) is a mature T-cell lymphoma of blood or lymph vessel immunoblasts characterized by a polymorphous lymph node infiltrate showing a marked increase in follicular dendritic cells (FDCs) and high endothelial venules (HEVs) and systemic involvement.[1] It is also known as immunoblastic lymphadenopathy (Lukes-Collins Classification) and AILD-type (lymphogranulomatosis X) T-cell lymphoma (Kiel Classification)[1]

Epidemiology

The typical patient with angioimmunoblastic T-cell lymphoma (AILT) is either middle-aged or elderly, and no gender preference for this disease has been observed.[1] AILT comprises 15-20% of peripheral T-cell lymphomas and 1-2% of all non-Hodgkin lymphomas.[3]

Clinical features

Etiology

This disease was originally thought to be a premalignant condition, termed angioimmunoblastic lymphadenopathy, and this atypical reactive lymphadenopathy carried a risk for transformation into a lymphoma. Currently, it is postulated that the originating cell for this disease is a mature (post-thymic) CD4+ T-cell that arises de novo,[1] although some researchers argue that there is a premalignant subtype of this disease.[4][5] The Epstein–Barr virus (EBV) is observed in the majority of cases,[1] and the virus has been found in the reactive B-cells that comprise part of the polymorphous infiltrate of this disease[6] and in the neoplastic T-cells.[7] Immunodeficiency is also seen with this disease, but it is a sequela to the condition and not a predisposing factor.[1]

Clinical presentation

Patients with this disease usually present at an advanced stage and show systemic involvement. The clinical findings typically include a pruritic skin rash and possibly edema, ascites, pleural effusions, and arthritis.[8][9]

Laboratory findings

The classical laboratory finding is polyclonal hypergammaglobulinemia, and other immunoglobulin derangements are also seen, including hemolytic anemia with cold agglutinins, circulating immune complexes, anti-smooth muscle antibodies, and positive rheumatoid factor.[1][8]

Sites of involvement

Due to the systemic nature of this disease, neoplastic cells can be found in lymph nodes, liver, spleen, skin, and bone marrow.

Morphology

Lymph node

The normal architecture of a lymph node is partially effaced by a polymorphous infiltrate and residual follicles are commonly seen. The polymorphous infiltrate consists of lymphocytes of moderate size with pale/clear cytoplasm and smaller reactive lymphocytes, eosinophils, histiocytes, plasma cells, and follicular dendritic cells. In addition, blast-like B-cells are occasionally seen. A classic morphological finding is the aborization and proliferation of high endothelial venules.[1] Hyperplastic germinal centers and Reed-Sternberg cells can also be seen.[10][11]

Molecular findings

Immunophenotype

AILT typically has the phenotype of a mixture of CD4+ and CD8+ T-cells, with a CD4:CD8 ratio greater than unity. Polyclonal plasma cells and CD21+ follicular dendritic cells are also seen.[1]

Genetic findings

Clonal T-cell receptor gene rearrangements are detected in 75% of cases,[12] and immunoglobin gene rearrangements are seen in 10% of cases, and these cases are believed to be due to expanded EBV-driven B-cell populations.[13] Similarly, EBV-related sequences can be detected most cases, usually in B-cells but occasionally in T-cells.[6][7] Trisomy 3, trisomy 5, and +X are the most frequent chromosomal abnormalities found in cases.[14] [15]

See also

References

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.