A case of CD30+ nasal natural killer/T-cell lymphoma.

Extranodal nasal natural killer (NK)/T-cell lymphoma is a very rare lymphoma characterized by strong association with Epstein-Barr virus infection, very aggressive clinical behavior, and poor prognosis. The typical phenotype of neoplastic natural killer cells in this entity is as follows: CD2+, CD56+, surface CD3-, cytoplasmic CD3epsilon+, and cytotoxic granule-associated protein positive. CD30 expression, a phenotype characteristic of anaplastic large-cell lymphomas, is not a typical feature of nasal NK/T-cell lymphomas. We describe the case of a 42-year-old woman with chronic nasal congestion and septal deviation who presented with progressive generalized tender erythematous plaques. A skin biopsy revealed an atypical angiocentric mononuclear cell infiltrate. Strong CD30 and CD3e immunoreactivities were noted in large atypical mononuclear cells within the infiltrate initially suggestive of a CD30+ T-cell lymphoma. However, flow cytometry of the skin lesion indicated that the cells were CD2+, CD4-, CD8-, and lacked surface CD3 more typical of a neoplasm of natural killer cells. Further studies revealed that the cells were CD56+, T-cell-restricted intracellular antigen-1+, and contained Epstein-Barr virus sequences consistent with a nasal-type NK/T-cell lymphoma. High titers of Epstein-Barr virus in the blood, evidence of sinonasal disease, and absence of a T-cell receptor gene rearrangement were additional features consistent with the diagnosis. The patient had a very aggressive clinical course and, despite combination chemotherapy, died 8 months after the onset of skin lesions. This case represents an example of nasal-type NK/T-cell lymphoma with expression of CD30. When presenting in the skin, the phenotypic and morphologic features of this lymphoma may lead to an erroneous diagnosis of a CD30+ large-T-cell lymphoma.