In a 79-year-old white woman, a lymphoproliferative disorder that was associated with type 2 Epstein-Barr virus (EBV) infection or reactivation, documented by three subsequent lymph node biopsies, was studied. After an initial phase with features of reactive lymphadenopathy with exhaustion of the follicular germinal centers and depletion of the B-cell lymphoid population, the disease evolved to a T-cell-rich lymphoma in which a clonal cell population of probable B-cell origin was identified. Such clonal cell population harbored the viral genome and expressed EBV latent membrane protein-1 but not EBV nuclear antigen-2. The implications of immunologic interactions between the clonal EBV-infected cells and the reactive T-cell component in the pathogenetic process are discussed.