Epstein Barr virus involvement in the pathogenesis of Diffuse B Cell Lymphoma in pediatric patients

COHEN, M; VISTAROP A; NARBAITZ, M; METREBIAN, F; PRECIADO MV; PAOLA ANDREA CHABAY

Rio de Janeiro

Congreso; World Society of Pediatric Infectious Diseases Congress 2015; 2015

World Society of Pediatric Infectious Diseases

DLBCL is one frequent malignancy in childhood. In Argentina, children are EBV+ quite early in their life and usually asymptomatic. EBV is associated with early development of lymphomas in our population. EBV-positive diffuse large B-cell lymphoma (EBV+ DLBCL) of the elderly is an entity included in the 2008 WHO classification of lymphoid tumors that occurs in immunocompetent patients >50 years old. It was related to the immunosenescence inherent to the aging process. Current literature does not establish a definitive EBERs cutoff to define an EBV+-DLBCL case. Our aim was to study the role of EBV in DLBCL pathogenesis in pediatric patients from our country and to characterize tumor microenvironment. Twenty-six DLBCL cases were collected. EBERs in situ hybridization and immunohistochemistry for EBNA2, EBNA3A, LMP1, LMP2A and BMRF1 viral antigens and CD4, CD8, Foxp3, GrB, PD-1 and IL-10 cell markers were performed. EBV gene expression, TGF, IL-10, IFN and CCL-20 transcripts were measured using real-time PCR. EBV+ and - cases were compared. EBV+ DLBCL frequency was 35% (9/26) using >20% EBERs+ tumor cells as a cutoff value; the viral latency patterns II-III together with lytic expression were prevalent. GrB+ cells were markedly increased in EBV+ DLBCL cases, in which a trend to lower event-free survival was noticed. In conclusion, EBV+ DLBCL may be an entity that is not only restricted to patients who are older than 50 years of age, in consequence the revision of age cutoff may be a current goal.