T-cell/Histiocyte-rich B-cell Lymphoma

Background: T-cell/histiocyterich B-cell lymphoma (T/HRBCL) is an uncommon morphologic variant of diffuse large B-cell lymphoma (DLBCL), representing less than 10% of all DLBCL cases. T/HRBCL has attracted considerable attention as a result of the difficult task of distinguishing it from similar entities, such as nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), classic Hodgkin lymphoma and peripheral T/cell lymphoma, nonspecific.
Case report: We present the case of a 70-year-old female patient addressing her primary care physician for headaches, nausea and a large, painful tumor in her left axilla. The paraclinical examinations revealed minimal deviations of hematological tests, but showed elevated LDH values. Surgery was performed and a specimen, composed of 13 lymph nodes, (the largest one having the surface diameter of 130 mm) was removed and examined histologically. On microscopic evaluation, the HE stain showed portions of lymph node completely effaced and replaced by a vaguely nodular lymphoid proliferation composed of scattered, large cells, with abundant cytoplasm, multilobated vesicular nuclei and proeminent nucleoli, consistent with lymphocytes and histiocytes. The immunohistochemical study proved the proliferative mass to be constituted of a limited number of large, CD20 positive B-cells, with proeminent nucleolus, in a background of CD3 positive T-cells, together with a variable number of histiocytes, highlighted with CD68. The large B-cells were scattered and did not form any clusters or strips. A diagnosis of T/HRBCL was made.
Conclusion: T/HRBCL is a rare variant of DLBCL, with an aggressive clinical outcome. In such cases immunohistochemical analyses are mandatory to reach correct diagnosis.