EBV-positive nodular lymphocyte predominant Hodgkin lymphoma: a single institution experience

The objective of this study is to characterize the clinicopathologic features of Epstein-Barr virus (EBV)-positive nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) at a single institution. A retrospective review of cases diagnosed with EBV-positive NLPHL was performed and the patients' demographic and pathologic features were collected by chart review. In this study, we identified 17 EBV-positive NLPHL patients whose clinicopathologic features are characterized. EBV was positive in lymphocyte predominant (LP) cells in 6 of 17 cases, whereas the remaining cases showed EBV positivity in background small cells. Immunohistochemical analysis showed that LP cells were positive for CD20 (94.1%) in most cases and positive for OCT2 (100%) in all cases with one case showing weak OCT2 expression, whereas PAX5 and CD79a were weak and/or variable in 9 of 12 and 3 of 7 cases, respectively. CD30 was positive in 7 of 17 cases with 5 cases showing only scattered positive cells. In addition, we report a patient who had a history of EBV-negative NLPHL and showed EBV-positive NLPHL at the time of recurrence. Molecular studies performed on the 2 biopsies in the patient indicated EBV infection involving the NF-kB pathway. Our study shows that EBV-positive NLPHL is rare and may be diagnostically challenging because of atypical immunophenotypic features, such as partial expression of CD30, and weak/variable PAX5 and/or CD79a expression. The overall retention of the B-cell phenotype with strong and diffuse expression of CD20 and OCT2 in LP cells supports the diagnosis of EBV-positive NLPHL.