CD20-positive T-cell lymphoma with indolent clinical behaviour

T-cell lymphomas that are positive for CD20 are very rare and most reported cases have demonstrated an aggressive clinical course. An unusual case of a 57-year old female who presented with recurrent enlarged lymph nodes for 12 years is reported. The lymph nodes from both 1995 and 2007 showed effacement of the lymph node architecture by a diffuse and dense infiltrate of small lymphoid cells. In terms of T- and B-cell markers, these small lymphoid cells were immunohistochemically positive for CD2, CD3, CD5, CD43, CD45RO and CD20, and were negative for PAX5, CD79a and cyclin D1. Molecular genetic analysis showed T-cell receptor-gamma chain gene rearrangement. Recognition of this type of CD20-positive T-cell lymphoma is important for ensuring a correct diagnosis so that the patient can be offered the most appropriate therapy. The indolent behaviour of the present case is unusual and awaits further clinical follow-up and laboratory investigation.