CD30 antigen in non‐Hodgkin's lymphoma

Expression of the CD30 antigen in lymphoid neoplasms and reactive lesions were examined immunohistologically using the monoclonal antibody BerH2. CD30 antigen was expressed in 17 of 18 patients with Hodgkin's disease (HD), all of three anaplastic large cell lymphomas (ALCL), 11 of 52 T‐cell malignant lymphomas (TML) including ALCL, 13 of 153 B‐cell malignant lymphomas (BML) including ALCL, two of three malignant histiocytosis and one of four plasmacytomas, Although a single case of small cell lymphoma was positive, in cases of mixed cellular morphology, neoplastic cells of larger or more pleomorphic nuclei tended to be stained more extensively and intensively. This antigen is expressed in TML significantly more often than in BML (P 0.05). CD30 antigen was expressed less frequently at clinical stage I than those of stages II to IV. There was no significant relationship between CD30 antigen expression and that of proliferating cell nuclear antigen or CD43 antigen in non‐Hodgkin's lymphomas (NHL). The CD30 antigen expression did not affect the prognosis of NHL overall, but in high grade TML, CD30 antigen‐positive individuals tended to have a more favorable prognosis than those that were negative. In reactive diseases, some plasma cells, immunoblasts, interdigitating cells, follicular center cells and histiocytes were stained positively, but not always, and with variable intensity. These results suggest that CD30 antigen is expressed In various cell lineages to some extent and may relate to cellular activation in some instances. When making the histopathologic diagnosis of HO or NHL including ALCL, CD30‐positive cell should be carefully interpreted. The authors believe that the name‘Ki‐1 lymphoma’or‘KM positive lymphoma’as a synonym of ALCL should therefore be abandoned.