Nasal NK/T-cell lymphoma with cutaneous involvement: a clinicopathologic and immunohistochemical study

Objective To explore the clinicopathological and immunohistochemical features of nasal NK/T-cell lymphoma with cutaneous involvement. Methods 3 cases of NK/T-cell lymphoma in nasal cavity with cutaneous involvement were analyzed by morphological examination and immunohistochemical staining. Results 3 patients presented with secondary cutaneous diseases in several months after diagnosis of nasal NK/T-cell lymphoma, and then died within one year. Both lesions of skin and nasal cavity shared common morphologic features, and their immuno-phenotypes were coincident with that of extranodal nasal type NK/T-cell lymphoma. Tumor cells were positive for LCA, CD56, TIA-1, cytoplasmic CD3 and CD2 , and negative for surface CD3 . Immunostaining showed that some tumor cells were also EBV positive in the 2 cases. The proliferative index of all the 3 cases were beyond 85% according to Ki-67 positive staining. Conclusions Nasal NK/T-cell lymphoma is a high-grade malignancy with obvious tendency to involve the skin and has poor prognosis. Its diagnosis and differential diagnosis may depend on characteristic morphology and immuno-phenotype.