Paraneoplastic Phenomena and Diagnostic Challenges in Angioimmunoblastic T-Cell Lymphoma (AITL): Report of Two Cases and Review of the Literature

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 auto immune reactions may represent the first clinical signs, resulting in delayed diagnosis and treatment. Case Report: 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. Conclusion: 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.