Cutaneous
peripheral T-cell lymphoma unspecified is a rare
neoplasm that is infrequently associated with Epstein-Barr virus (
EBV) infection. In contrast, extranodal natural killer (NK)/
T-cell lymphoma, although also rare, is known to be strongly associated with EBV and occurs most commonly in the nasal region. We report the case of a 55-year-old male who presented with
fever and an indurated cutaneous plaque with ulceration. This cutaneous
neoplasm showed diffuse dermal lymphomatous infiltration and
tumor necrosis, with neoplastic cells expressing CD2, cytoplasmic CD3 (CD3ε), CD8, CD16, CD30,
T-cell intracellular antigen-1, and
granzyme B but not CD56, BF1, or
T-cell receptor (TCR) δ1. Furthermore, the
tumor cells were noted to be diffusely positive for EBV by in situ hybridization. A monoclonal TCR gene rearrangement was demonstrated. The disease showed an aggressive
clinical course, and the patient died within 3 weeks of diagnosis without complete staging or
chemotherapy. According to the 2005 World Health Organization/European Organization for Research and Treatment of
Cancer scheme for cutaneous
lymphoma and the 2008 WHO classification for lymphoid
neoplasms, our case would have been classified as a nasal type
extranodal NK/T-cell lymphoma with T-cell lineage. However, the expressions of CD8 and CD16, in addition to a monoclonal TCR gene rearrangement, are unusual findings in NK/
T-cell lymphoma, and we believe such a phenotype/genotype should be more appropriately classified as an EBV-positive
peripheral T-cell lymphoma, unspecified with a cytotoxic phenotype. Detailed clinicopathologic and molecular studies of similar cases may shed light on the prognostic impact of NK vs. T-cell lineage on
extranodal NK/T-cell lymphomas.