Angioimmunoblastic T-cell lymphoma
Template:Infobox Disease Angioimmunoblastic T-cell lymphoma (AILT) (also known as "Angioimmunoblastic lymphadenopathy with dysproteinemia":747) is a mature T-cell lymphoma with systemic characterized by a polymorphous lymph node infiltrate showing a marked increase in follicular dendritic cells (FDCs) and high endothelial venules (HEVs) and systemic involvement. It is also known as immunoblastic lymphadenopathy (Lukes-Collins Classification) and AILD-type (lymphogranulomatosis X) T-cell lymphoma (Kiel Classification)
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. AILT comprises 15-20% of peripheral T-cell lymphomas and 1-2% of all non-Hodgkin lymphomas.
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, although some researchers argue that there is a premalignant subtype of this disease. The Epstein Barr virus (EBV) is observed in the majority of cases, and the virus has been found in the reactive B-cells that comprise part of the polymorphous infiltrate of this disease and in the neoplastic T-cells. Immunodeficiency is also seen with this disease, but it is a sequela to the condition and not a predisposing factor.
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.
The classical laboratory finding is polyclonal hypergammaglobulinemia, and other immunoglobulin derrangements are also seen, including hemolytic anemia with cold agglutinins, circulating immune complexes, anti-smooth muscle antibodies, and positive rheumatoid factor.
Sites of involvement
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. Hyperplastic germinal centers and Reed-Sternberg cells can also be seen.
Clonal T-cell receptor gene rearrangements are detected in 75% of cases, 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. Similarly, EBV-related sequences can be detected most cases, usually in B-cells but occasionally in T-cells.. Trisomy 3, trisomy 5, and +X are the most frequent chromosomal abnormalities found in cases. 
- ↑ James, William D.; Berger, Timothy G.; et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. ISBN 0-7216-2921-0.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8  Jaffe E.S., Harris N.L., Stein H., Vardiman J.W. (eds): World Health Organization Classification of Tumors. Pathology and Genetics of Tumours of Haemopoietic and Lymphoid Tissues. IARC Press: Lyon 2001
- ↑ [Expression error: Missing operand for > "A clinical evaluation of the International Lymphoma Study Group classification of non-Hodgkin's lymphoma. The Non-Hodgkin's Lymphoma Classification Project"]. Blood 89 (11): 3909–18. June 1997. PMID 9166827.
- ↑ Frizzera G, Kaneko Y, Sakurai M (January 1989). [Expression error: Missing operand for > "Angioimmunoblastic lymphadenopathy and related disorders: a retrospective look in search of definitions"]. Leukemia 3 (1): 1–5. PMID 2642571.
- ↑ Smith JL, Hodges E, Quin CT, McCarthy KP, Wright DH (February 2000). [Expression error: Missing operand for > "Frequent T and B cell oligoclones in histologically and immunophenotypically characterized angioimmunoblastic lymphadenopathy"]. Am. J. Pathol. 156 (2): 661–9. PMID 10666395.
- ↑ 6.0 6.1 Weiss LM, Jaffe ES, Liu XF, Chen YY, Shibata D, Medeiros LJ (April 1992). [Expression error: Missing operand for > "Detection and localization of Epstein-Barr viral genomes in angioimmunoblastic lymphadenopathy and angioimmunoblastic lymphadenopathy-like lymphoma"]. Blood 79 (7): 1789–95. PMID 1373088.
- ↑ 7.0 7.1 Anagnostopoulos I, Hummel M, Finn T, et al. (October 1992). [Expression error: Missing operand for > "Heterogeneous Epstein-Barr virus infection patterns in peripheral T-cell lymphoma of angioimmunoblastic lymphadenopathy type"]. Blood 80 (7): 1804–12. PMID 1327284.
- ↑ 8.0 8.1 Siegert W, Nerl C, Agthe A, et al. (September 1995). [Expression error: Missing operand for > "Angioimmunoblastic lymphadenopathy (AILD)-type T-cell lymphoma: prognostic impact of clinical observations and laboratory findings at presentation. The Kiel Lymphoma Study Group"]. Ann. Oncol. 6 (7): 659–64. PMID 8664186.
- ↑ Jaffe ES (September 1995). [Expression error: Missing operand for > "Angioimmunoblastic T-cell lymphoma: new insights, but the clinical challenge remains"]. Ann. Oncol. 6 (7): 631–2. PMID 8664181.
- ↑ Quintanilla-Martinez L, Fend F, Moguel LR, et al. (October 1999). [Expression error: Missing operand for > "Peripheral T-cell lymphoma with Reed-Sternberg-like cells of B-cell phenotype and genotype associated with Epstein-Barr virus infection"]. Am. J. Surg. Pathol. 23 (10): 1233–40. doi:10.1097/00000478-199910000-00008. PMID 10524524.
- ↑ Ree HJ, Kadin ME, Kikuchi M, et al. (June 1998). [Expression error: Missing operand for > "Angioimmunoblastic lymphoma (AILD-type T-cell lymphoma) with hyperplastic germinal centers"]. Am. J. Surg. Pathol. 22 (6): 643–55. doi:10.1097/00000478-199806000-00001. PMID 9630171.
- ↑ Feller AC, Griesser H, Schilling CV, et al. (December 1988). [Expression error: Missing operand for > "Clonal gene rearrangement patterns correlate with immunophenotype and clinical parameters in patients with angioimmunoblastic lymphadenopathy"]. Am. J. Pathol. 133 (3): 549–56. PMID 2849301.
- ↑ Lipford EH, Smith HR, Pittaluga S, Jaffe ES, Steinberg AD, Cossman J (February 1987). [Expression error: Missing operand for > "Clonality of angioimmunoblastic lymphadenopathy and implications for its evolution to malignant lymphoma"]. J. Clin. Invest. 79 (2): 637–42. doi:10.1172/JCI112860. PMID 3805286.
- ↑ Kaneko Y, Maseki N, Sakurai M, et al. (August 1988). [Expression error: Missing operand for > "Characteristic karyotypic pattern in T-cell lymphoproliferative disorders with reactive "angioimmunoblastic lymphadenopathy with dysproteinemia-type" features"]. Blood 72 (2): 413–21. PMID 3261178.
- ↑ Schlegelberger B, Zhang Y, Weber-Matthiesen K, Grote W (October 1994). [Expression error: Missing operand for > "Detection of aberrant clones in nearly all cases of angioimmunoblastic lymphadenopathy with dysproteinemia-type T-cell lymphoma by combined interphase and metaphase cytogenetics"]. Blood 84 (8): 2640–8. PMID 7919378.