In March 2019, a 83-year-old Chinese male was admitted to our hospital due to a month history of enlarged lymph nodes in the neck and bilateral inguinal without pain and fever. Computed tomography (CT) scan disclosed generalized lymphadenopathy in the mediastinum, hilum, bilateral inguinal, right lung, right kidney. However, the complete blood count, coagulation markers, albumin, lactate dehydrogenase(LDH), creatinine, β2 -microglobulin and alanine aminotransferase(ALT) were all normal. The laboratory of EBV viral IgM-capsid antigen (VCA) and EBV-DNA were strongly positive. Then, the patient underwent biopsy of left inguinal lymph node, a large number of diffuse large sized proliferation atypical lymphoid cells can be seen under microscope. Immunohistochemically (IHC), the atypical cells were strongly positive for CD20, CD19, PAX-5 and MUM-1, but negative for CD3, CD5, CD10, Bcl-6, CyclinD1, CD138 and TdT (Fig. 1). C-myc and Bcl-2 were expressed by more than 60% and 20% of lymphoma cells. Ki67 was expressed by more than 80% of lymphoma cells. Besides, in situ hybridization for EBV-encoded small RNA (EBER) staining was also strongly positive. Bone marrow aspiration and trephine biopsy showed no infiltration. Based on the above, a pathological diagnosis of EBV-positive DLBCL was made. After the diagnosis of EBV-positive DLBCL, the patient received eight cycles of R-miniCHOP(rituximab, cyclophamide, doxorubicin, vincristine and prednisone) therapy, but his symptoms did not disappear and PET/CT scan showed no signs of complete remission (CR) or partially remission (PR) after treatment. The disease status was stable despite the immune-chemotherapy administration.
In March, 2020, one year after initial diagnosis of EBV-positive DLBCL, the patient was readmitted to our hospital again because of nasopharyngeal discomfort. CT scan revealed multiple enlargements of mediastinum, hilum, bilateral inguinal, right lung, right kidney lymph nodes and thickened nasopharyngeal wall. Bone marrow aspiration was normal. A left inguinal lymph node biopsy was performed, and to our surprise, it revealed ngioimmunoblastic T-cell lymphoma (AITL). Immunohistochemically, the cancer cells were positive for most pan-T cell antigens such as CD3, CD4, CD5, CD7, CD21 and T follicular helper (TFH) biomarkers including CD10, Bcl-6 and CXCL13, but negative for CD20, ALK, PD-1, EMA and Perforin (Fig. 2). Ki67 was expressed in more than 45% of lymphoma cells. EBERs showed strongly positive reaction. A diagnosis of AITL secondary to EBV-positive DLBCL was finally established. Since the patient showed poor response to the previous R-miniCHOP treatment, new strategy of therapy should be considered. So, the histone deacetylase inhibitor Chidamide and prednisolone were administered. The patient ultimately died of disease progression in July 3 2020 after three months when diagnosed AITL. The overall survival time of this patient is fifteen months.