Born with Two Faces: Sequential development of Diffuse Large B-cell Lymphoma and Angioimmunoblastic T-cell Lymphoma with EBV positive and TET2 mutation

Abstract

There may be significant histopathological and pathogenetic overlap between Epstein–Barr virus (EBV) -positive diffuse large B cell lymphoma (DLBCL) and other lymphomas, including angioimmunoblastic T-cell lymphoma (AITL). Herein, we reported a rare case of an AITL developing two years after the initial diagnosis of EBV-positive DLBCL. Next-generation sequencing (NGS) is used to study genetic mutations in biopsy samples of DLBCL and subsequent AITL. NGS revealed that TET2 mutated in both DLBCL and AITL, while other differential mutations were also detected, reflecting their own characteristics. Since inherent EBV infection plays a role in both AITL and DLBCL, we evaluated the characteristics of lymphoma associated with EBV infection, including morphology and treatment, etc. We deduce that chronic EBV infection and epigenetic TET2 mutations may alter the immune profile or tumor microenvironment of lymphoma cells, resulting in patients presenting with different tumor types at different times. Patients with AITL secondary to DLBCL have a poor prognosis, and the combination of chidamide and chemotherapy is expected to provide new treatment options for these patients, mainly due to the multiplex antitumor mechanism of chidamide in lymphoma.