Clinical analysis of 42 cases of EBV-positive mature T/NK-cell neoplasms.

The pathogenesis of Epstein-Barr virus-positive (EBV) mature T-cell and natural killer (NK)-cell neoplasms is challenging to understand. The clinical features are diverse, with no typical manifestation. Therefore, it is important to analyze the association of the clinical characteristics and prognoses of patients with various factors associated with EBV T/NK-cell neoplasms, particularly extranodal NK/T cell lymphoma, systemic EBV T/NK cell lymphoproliferative disorders, aggressive NK cell leukemia and EBV peripheral T-cell lymphoma. Therefore, 42 cases of EBV T/NK-cell neoplasms with information on age, gender, fever, LDH level, complete blood count (CBC) and immunophenotype (CD5/CD20) were retrospectively analyzed to examine the clinical features, prognoses and related factors. It was found that patients ≤60 years old accounted for 86% of cases. The frequency of stage III/IV disease was higher in groups with pancytopenia (P=0.005), high LDH level (P=0.020), CD5-expression status (P=0.031) and fever (P=0.024). There were significant differences in the mean International Prognostic Index (IPI) scores according to the presence or absence of fever (P=0.022), elevated or normal lactose dehydrogenase (LDH) levels (P=0.001), and pancytopenia or normal complete blood count (CBC; P=0.046). Analysis of overall survival showed that CD5 expression, CBC, IPI scores and LDH levels were factors associated with OS. CD5 expression (P=0.003), CBC (P=0.003) and IPI scores (P=0.017) were identified to be important risk factors on the basis of Cox regression analysis. The mean survival time was longer in the CD5, CD20 and normal CBC groups, and there was no clear difference in survival time according to LDH level or fever. In summary, CD5 and CD20 may be prognostic factors in EBV T/NK lymphoid neoplasms, and CBC and fever are most likely to influence the IPI score and Ann Arbor stage.