Clinicopathological findings of systemic Epstein-Barr virus-positive T-lymphoproliferative diseases in younger and older adults

Background Systemic Epstein-Barr virus + T-cell lymphoma (sEBV + TCL) occurs in childhood and young adults, and is exceptionally rare in older adults. Methods We investigated clinicopathological features in 16 patients of various ages with systemic EBV + CD8 + T-lymphoproliferative diseases. Results Eight younger patients and four of eight older adults had sEBV + CD8 + TCL, with invasion by medium-sized to/or large atypical lymphocytes primarily in bone marrow and lymph nodes, hemophagocytic lymphohistiocytosis (HLH), and progressive clinicopathological course. A further two patients demonstrated EBV + node-based CD8 + large TCL without HLH, while the remaining two had the systemic form of chronic active EBV infection (sCAEBV) with CD8 + small lymphocytes. Past history of sCAEBV-like lesions was observed in one sEBV + TCL patient (8.3%). Immunohistologically, in 12 sEBV + TCL patients, atypical lymphocytes were positive for phosphate signal transducer and activator of transcription 3 (66.7%), CMYC (83.3%), and p53 (75%). Strong reactions of programmed cell death-ligand (PD-L)1 + tumor or non-neoplastic cells were detected in nine sEBV + TCL patients (75%). Clonal peaks of the T-cell receptor ( TCR) γ gene were detected in eight sEBV + TCL patients by polymerase chain reaction. Four younger patients in sEBV + TCL (33.3%) are in remission with chemotherapies including etoposide, and three of the four underwent allogeneic stem cell transplantation (SCT). Conclusion sEBV + CD8 + TCL was observed in younger and older adults with less history of sCAEBV. HLH, tumor cell atypia, immunohistological findings, and progressive clinical course were characteristic of sEBV + CD8 + TCL. Prompt chemotherapy and SCT induced tumor regression in sEBV + CD8 + TCL patients.