[1367] Epstein-Barr Virus Expression in Diffuse Large B-Cell Lymphoma in the Immunocompetent
K Kersch, J Hussong, R Alsabeh. Cedars-Sinai Medical Center, Los Angeles, CA
Background: Diffuse large B-cell lymphoma (DLBCL) has been associated with EBV in the settings of chronic inflammation, HIV, and chronic immunosuppression. An entity of EBV positive DLBCL of the elderly has been described in which there is EBV expression without history of immunosuppression. These cases have been attributed to immunologic senescence allowing for the development of an EBV-driven DLBCL, with the majority of data from Asia. In this study, we look at the frequency of EBV expression in DLBCL in a western immunocompetent population.
Design: 131 cases of DLBCL arising in non-immunosuppressed patients were queried for EBV status using a combination of EBER in-situ hybridization and EBV-LMP immunostain. Patients were classified by age (>50 yrs). Patients with HIV, post-transplant, or with history of immunodeficiency were excluded. Cases were reclassified according to the 2008 WHO DLBCL subtype and as germinal center-like/ non-germinal center-like based on immunohistochemistry. The proliferation rate by Ki-67 was also tabulated.
Results: Majority of patients (103/131) were >50 yrs. 3/131 (2.3%) of the cases show EBV expression and all 3 cases were >50 yrs (age 61-88 yrs). None of the DLBCL cases in patients <50 yrs show EBV expression. None of the EBV positive cases were of East Asian descent. 56.2% of the patients >50 yrs had a germinal center-B-cell like (GCB) immunophenotype, in contrast to 73.7% for those <50 yrs. Proliferation rates were the same amongst the groups.
| Subtypes | Cases overall | EBV+ |
|---|---|---|
| DLBCL, NOS | 97/131 | 2/131 |
| Mediastinal | 9/131 | 0/131 |
| Unclassifiable, with features intermediate between DLBCL and Burkitt Lymphoma | 8/131 | 1/131 |
| CNS | 11/131 | 0/131 |
| Unclassifiable, with features intermediate between DLBCL and Classical Hodgkin Lymphoma | 2/131 | 0/131 |
| ALK+ | 1/131 | 0/131 |
| Intravascular | 1/131 | 0/131 |
| Leg type | 1/131 | 0/131 |
| T-Cell rich | 1/131 | 0/131 |
| EBV + | GC-like/total | East Asian | Ave. prolif. rate | |
|---|---|---|---|---|
| Age>50 | 3/103 (2.9%) | 50/89 (56.2%) | 8/103 (7.7%) | 75% n=98 |
| Age<50 | 0/28 (0%) | 14/19 (73.7%) | 1/28 (3.6%) | 76% n=27 |