Early diagnosis of recurrent diffuse large B-cell lymphoma showing intravascular lymphoma by random skin biopsy.

A 66-year-old man was admitted to our hospital presenting 2 weeks' history of fever of unknown origin with elevated levels of lactate dehydrogenase and C-reactive protein. Six years before this episode, he had developed diffuse large B-cell lymphoma, which had been successfully treated with chemoradiation. While recurrence of diffuse large B-cell lymphoma was suspected, there was neither lymphadenopathy nor tumor formation by the imaging study. Random biopsy from normal-appearing abdominal skin showed extensive infiltration of CD20(+), CD79a(+), CD3(-) atypical lymphoid cells in the lumen of vessels in subcutaneous tissues. These findings led us to the diagnosis of intravascular B-cell lymphoma. Following rituximab plus cyclophosphamide, adriamycin, vincristine and prednisolone therapy, high fever subsided, and lactate dehydrogenase and C-reactive protein levels returned to the normal range. In conclusion, random skin biopsy is useful for the early diagnosis of intravascular B-cell lymphoma.