Cutaneous intravascular NK-cell lymphoma: report of a rare variant associated with Epstein-Barr virus.

Intravascular lymphoma (IVL) is a rare variant of non-Hodgkin lymphoma with a predilection for skin and brain. Except a few cases of T-cell lineage, most of the reported cases were large B-cell lymphomas. We encountered a case of cutaneous IVL in a 71-year-old woman presenting with multiple erythematous patches and nodules on her trunk and extremities. The intravascular large cells showed an immunophenotype of CD3epsilon(+);, CD5(-), CD20(-), CD30(-), CD56(+), and TIA-1(+). The lymphoma cells were also positive for Epstein-Barr virus by Epstein-Barr virus-encoded RNA in situ hybridization test and the T-cell receptor gene was germline. This IVL differs from nasal type NK/T-cell lymphoma only by its intravascular nature. Only 3 cases of intravascular NK-cell lymphoma have been reported before. Because this variant is extremely rare, our case is documented and compared with the 3 previously reported cases.