title: Paraneoplastic phenomena and diagnostic challenges in angioimmunoblastic T-cell lymphoma (AITL): report of two cases and review of the literature.
abstract: BACKGROUND
  Angioimmunoblastic T-cell lymphoma (AITL) is an aggressive subtype of peripheral T-cell lymphoma with unique clinical, pathological and genetic features. Clinical diagnosis is often hampered as typical lymphoma-associated symptoms may not be found at the time of first presentation and only occur later during disease progression. However, as AITL leads to a de-regulated immune system, various paraneoplastic syndromes or autoimmune reactions may represent the first clinical signs, resulting in delayed diagnosis and treatment.
  
  
  METHODS
  We herein describe two AITL cases characterized by a fatal clinical course and the occurrence of unusual paraneoplastic phenomena, including fluid retention and disseminated intravascular coagulation, respectively. Despite multiple diagnostic procedures, both patients died of rapid disease progression and definitive diagnoses could only be established post-mortem.
  
  
  CONCLUSIONS
  These cases underscore the complex diagnostic challenges of AITL and illustrate the requirement for careful clinical evaluation and prompt integration of different diagnostic parameters, including immunohistochemistry, flow cytometry, conventional cytogenetics and molecular genetics, to enable adequate and prompt therapeutic interventions.
authors.affiliation: Department of Internal Medicine V, Medical University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria. andreas.pircher@i-med.ac.at.
authors.forename: Andreas
authors.initials: A
authors.lastname: Pircher
authors.forename: Irmgard
authors.initials: I
authors.lastname: Verdorfer
authors.forename: Andrea
authors.initials: A
authors.lastname: Brunner
authors.forename: Georg
authors.initials: G
authors.lastname: Hopfinger
authors.forename: Michael
authors.initials: M
authors.lastname: Steurer
mesh_terms: D000368:Aged; D001706:Biopsy; D001853:Bone Marrow / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007119:Immunoblastic Lymphadenopathy / Q000473:pathology*; D007150:Immunohistochemistry; D016411:Lymphoma, T-Cell, Peripheral / Q000175:diagnosis* / Q000473:pathology*; D008297:Male; D010257:Paraneoplastic Syndromes / Q000175:diagnosis* / Q000473:pathology*; D049268:Positron-Emission Tomography; D013154:Spleen / Q000378:metabolism / Q000473:pathology
keywords: Angioimmunoblastic T-cell lymphoma (AITL); disseminated intravascular coagulopathy (DIC); paraneoplastic syndromes (PS); syndrome of inappropriate antidiuretic hormone secretion (SIADH)