[Immunologic phenotypes of germinal center cell tumors]

A panel of monoclonal antibodies applied to frozen sections of non-Hodgkin's lymphomas was used to establish clear-cut differences among the different entities of malignant lymphomas of germinal centre cell origin. 51 cases (18 centrocytic, 25 centroblastic-centrocytic and 8 centroblastic lymphomas) were included in this study. A clear-cut difference in the expression of the T65 antigen (Leu 1+) and the common acute lymphoblastic leukaemia antigen (CALLA) was found. Thus, centrocytic lymphomas predominantly expressed Leu 1, but not CALLA, whereas centroblastic-centrocytic lymphomas were always positive for CALLA, but not for the T65 antigen. Centroblastic lymphomas are virtually never positive with respect to either antibody. These findings suggest that, perhaps, two different phenotypes of centrocyte exist in centrocytic and centroblastic-centrocytic lymphomas.