Immunohistochemical study of diffuse large cell hymphomas using monoclonal and polyclonal antibodies comparing routinely fixed paraffin embedded tissue and frozen sections

Abstract

48 cases of diffuse large cell lymphomas (DLCLs) from Zurich were morphologically classified according to the Kiel Classification of non-Hodgkins lymphomas (NHL) and immunologically into large centrocytic 7 cases, centroblastic 23; B immunoblastic 10, peripheral T cell lymphomas (PTCLs) 6, and true histiocytic sarcoma 2 cases. 73% of the cases were of B cell, 23% of T cell and 4% of true histiocytic origin. Immunohistochemically Anti-leucocyte common antigen (LCA) PD7/26, 2B11 showed concordant immunoreactivity with 66% of DLCLs. LN2 and MB2 proved reliable B cell markers by reacting with 70% and 74% of B cell DLCLs respectively. None of the T cell lymphomas showed reactivity with these antibodies. UCHL1 proved a better T cell marker than MT1 by reacting with 72% of PTCLs against 45% of the latter. In addition 2 true histiocytic sarcomas were identified by immunophenotyping using appropriate markers. Light chain polytypic antibodies did not prove useful in detecting B cell DLCLs. Comparatively, immunophenotyping of 32 cases of DLCLs from Dar es Salaam showed 90% to be of B cell and 10% of T cell origin. Antibody PD 7/26, 2B11 showed immunoreactivity with 50% of the cases. LN1 and LN2 showed much lower percentage of immunoreactivity with B cell DLCLs than Zurich series. 2 of the 3 T cell DLCLs reacted with UCHL1.