Summary

T-cell/histiocyte rich large B-cell lymphoma (THRLBCL) is a rare variant of diffuse large B-cell lymphoma (DLBCL) with an aggressive behaviour. Clinically, THRLBCL affects a young, predominantly male population. Pathologically, it is characterised by fewer than 10% of large neoplastic B-cells in a background of abundant T-cells with or without the presence of histiocytes. Differentiating THRLBCL from other lymphoproliferative disorders can be difficult but is achieved by morphologic and immunohistochemical characterisation of the tumour cells in the appropriate stromal microenvironment. Despite these clinical and pathologic differences, treating THRLBCL is not different from treating stage-matched DLBCL and can result in a comparable outcome. Comparative studies, however, on outcome of THRLBCL and DLBCL are methodologically weak and include small numbers of patients. Recently, gene expression profiling showed a predominant role for a distinct host immune response in THRLBCL, leading to tumor tolerance. Targeting specific molecules responsible for this tumour tolerance could lead to novel therapeutic options.

(BELG J HEMATOL 2012;3: 128–133)