Prognostic impact of pre-treatment and post-treatment plasma Epstein-Barr virus DNA in peripheral T-cell lymphomas

BACKGROUND: Plasma Epstein-Barr virus (EBV) DNA levels predict the prognosis of extranodal NK/T-cell lymphoma, nasal type (NK/TCL), but its role in other peripheral T-cell lymphomas (PTCL) remains undetermined. This study aimed to determine the prognostic impact of plasma EBV DNA in PTCL patients.

METHODS: We retrospectively enrolled 134 PTCL patients diagnosed between April 2008 and March 2022, with plasma EBV DNA data available at diagnosis in 124 patients and during post-treatment follow-up in 73 patients.

RESULTS: International Prognostic Index or prognostic index for T-cell lymphoma scores > 1 was associated with higher median plasma EBV DNA levels in all analyzed patients. Plasma EBV DNA positivity at the time of diagnosis was not associated with treatment response, overall survival (OS), or progression-free survival (PFS) in non-NK/TCL patients. In NK/TCL patients, an EBV DNA level < 3255 copies/mL at diagnosis was significantly associated with higher five-year PFS (64.2% vs. 16.7%, p  < 0.001) and OS rates (64.4% vs. 20.8%, p  < 0.001). Plasma EBV DNA positivity at the time of complete remission and during post-treatment follow-up was significantly linked to lower PFS and OS rates in NK/TCL patients. Multivariate analysis revealed that advanced-stage disease, elevated β2-microglobulin, and EBV DNA level ≥ 3255 copies/mL at diagnosis were independent predictors for OS and PFS in NK/TCL patients.

CONCLUSIONS: Plasma EBV DNA at diagnosis and during follow-up predict survival for NK/TCL patients but not for patients with other PTCL subtypes. Detection and monitoring of plasma EBV DNA levels at diagnosis and post-treatment follow-up for NK/TCL patients is recommended.