Paraffin section immunophenotyping of non-Hodgkin's lymphoma, using a panel of monoclonal antibodies

The monoclonal antibodies F8-11-13, 4KB5, MB1, and MB2 recognize largely B-cell-restricted antigenic determinants that resist routine processing. Similarly, MT1, MT2, and UCHL1 react with fixation-resistant T-cell-restricted antigens. In order to evaluate the diagnostic potential of these antibodies, the authors have assessed their immunoreactivity with a series of 81 formalin-fixed and paraffin-embedded non-Hodgkin's lymphomas (48 B-cell, 33 T-cell) encompassing a wide variety of histologic subtypes, which had been fully characterized by frozen-section immunophenotyping. Ninety-six percent of B-cell lymphomas reacted with one or more of the B-cell-associated antibodies, whereas 100% of T-cell lymphomas reacted either with MT1, UCHL1, or both antibodies. MT2 was of no value in distinguishing between B- and T-cell lymphomas. None of the antibodies was entirely lineage specific; furthermore, a proportion of cases failed to react with one or more of the B- or T-cell-associated antibodies. Although these antibodies provide useful information in distinguishing between T- and B-cell lymphomas, the authors suggest that a panel of these antibodies is necessary for accurate determination of the histogenesis of these tumors. As with any immunohistochemical marker, interpretation of the immunostaining must be in the context of the morphologic features.