Leu M‐1 antigen: Comparative expression in hodgkin's disease and T cell lymphoma

Abstract

Expression of the granulocyte antigen Leu M‐1 is characteristic of Reed–Sternberg cells and the related mononuclear cells of Hodgkin's Disease. Leu M‐1 has been proposed as a specific immunological marker for Hodgkin's Disease which may be otherwise difficult to distinguish both morphologically and immunologically from non Hodgkin's lymphomas of peripheral T‐cell type. In the present study the comparative expression of Leu M‐1 in Hodgkin's Disease and peripheral T cell lymphoma was studied in a series of 43 cases including 25 cases of Hodgkin's Disease and 18 cases of immunologically documented peripheral T cell lymphoma. Leu M‐1 staining by avidin‐biotin‐peroxidase complex technique in acetone fixed frozen sections was observed in 22 of 25 cases of Hodgkin's Diseases, (2 of 3 cases of lymphocyte predominant Hodgkin's Disease and 1 case of mixed cellularity were negative) and in 4 of 18 cases of peripheral T cell lymphoma. The pattern of staining in the peripheral T cell lymphomas was indistinguishable from that observed in Hodgkin's Disease in 2 of the cases. Leu M‐1 staining appears to be of limited diagnostic value in the differential diagnosis of Hodgkin's Disease and T cell lymphoma. Absence of Leu M‐1 staining in frozen tissue however, makes a diagnosis of Hodgkin's Disease (with the exception of the lymphocyte predominant form) unlikely.