Epstein-Barr virus-positive nodal T/NK-cell lymphoma: an analysis of 15 cases with distinct clinicopathological features.

Nodal peripheral T-cell lymphoma, not otherwise specified, is a heterogeneous entity with variable biologic behavior. We analyze the clinicopathological features of 15 patients with Epstein-Barr virus-positive (EBV+) nodal T/NK-cell lymphoma, including 9 males and 6 females, with a median age of 64 years. All patients presented with multiple lymphadenopathy with common B symptoms (80%, 12/15) at an advanced Ann Arbor stage (III, IV) (87%, 13/15). The International Prognostic Index was high or high/intermediate in 87% (13/15) of patients, and the prognostic index for peripheral T-cell lymphoma was group 3 or 4 in 73% (11/15). Spleen and liver involvement was observed in 73% (11/15) and 60% (9/15) of patients, respectively. In contrast, extranodal involvement was infrequent, with no more than 1 site in 71% (10/15) of patients. Moreover, none had nasal lesions, and only 1 had mucocutaneous involvement. The cell lineage of EBV+ tumor cells was determined to be T cell in all except 1 patient, who was NK-cell lineage. Cytotoxic molecules were expressed in all cases, and 64% (9/14) of patients expressed the αβT-cell receptor. Moreover, most patients (67%, 10/15) showed CD8 positivity, with 2 of them being CD4CD8 double positive; the others were CD4 positive (n = 2) or CD4CD8 double negative (n = 3). The clinical course was very aggressive, with a median survival time of 3.5 months, and 10 patients died within 6 months of diagnosis. Taken together, our data demonstrate that EBV+ nodal T/NK-cell lymphoma is a distinct clinicopathological entity characterized by cytotoxic molecule expression, a frequent CD8-positive αβT-cell lineage, and a very aggressive clinical behavior.