[Classification of malignant lymphomas--current status and clinical implications]

New techniques such as cytogenetics, molecular biology and immunology have provided new insights into the pathogenesis and development of malignant lymphomas. By this way they provided a new basis for a classification of lymphoid malignancies which is increasingly oriented on biology and pathogenesis. This process resulted in the 'Revised European-American Lymphoma' (R.E.A.L.) classification, which was recently proposed by an international group of pathologists. This classification comprises a preliminary end point of a continuing process which will require a reevaluation and adaptation to new knowledge in the future again. In order to facilitate the clinical use of this histopathologically and biologically oriented classification, a proposal for a clinical grouping was developed, which divides the R.E.A.L. lymphoma subtypes into the following categories: I. Indolent lymphomas (low risk group). II. Aggressive lymphomas (intermediate risk group). III. Very aggressive lymphomas (high risk group). IV. Morbus Hodgkin. This internationally developed consensus of a histopathologic classification and a clinical grouping is a substantial step forward towards an international cooperation in the management of malignant lymphomas. It is background for cooperative studies and justifies the hope that further advances will be achieved in the treatment of malignant lymphomas and that more effective strategies can be developed in the near future.