A Clinically and Morphologically Challenging Angioimmunoblastic T- cell Lymphoma Case. Anna Sarah Erem, Saja Asakrah

Summary: "Angioimmunoblastic T-cell lymphoma (AITL) is an aggressive subtype of peripheral T-cell lymphoma originating from follicular helper T-cells. AITL is characterized by abnormal immune and inflammatory response with a range of features that mimic inflammatory disorders. Clinicians from different disciplines may be involved in the care of such patients. Effective collaboration among clinicians is essential for rendering an accurate diagnosis. We present a 51-year-old male with a puzzling clinical course. Initially, he presented with multiple skin lesions and pleural effusion. Blood work revealed thrombocytopenia, and plasmacytosis. Imaging showed lymphadenopathy and splenomegaly. The patient underwent multiple inconclusive needle biopsies. Laboratory tests showed hypoalbuminemia, abnormal liver function test, and high levels of ferritin, triglyceride, soluble IL2 receptor, and IL6. Infection workup showed Epstein-Barr Virus (EBV) viremia. During hospitalization, the patient endured acute respiratory distress and cardiac arrhythmia. The patientʼs course instigated many discussions among physicians and raised the possibilities of EBV-associated hemophagocytic lymphohistiocytosis, EBV-driven lymphoma, and multicentric Castleman disease. Morphological evaluation of the subsequent lymph node biopsy confirmed the diagnosis of AITL. It showed partial architecture effacement by lymphohistiocytic infiltrates with frequent EBV positive plasmablasts/immunoblasts. CD4T-cells predominate and express T-follicular helper markers, including BCL6, PD1, and ICOS (Fig-1, A-D). Flow cytometry of the bone marrow biopsy, pleural effusion, and peripheral blood sample showed polytypic plasmablasts. HHV8 was negative. Treatment included CHOEP chemotherapy with excellent clinical response. This is an example of a challenging AITL case requiring extensive laboratory workup and efficient communication among the involved clinicians and pathologists to facilitate an accurate diagnosis."