Much of the attention presently paid to leukemia is the result of recent progress in understanding and treatment. Chemotherapy of leukemia started in the late 1940s, and combination therapy evolved in the late 1950s. It was at that time that the clonality of leukemia was realized, after the discovery of chromosomal and then biochemical and immunological markers. And now we have the new data on retroviral and cellular oncogenes and the reports on human T -cell lymphoma/ leukemia viruses. Many more steps forward could be enumerated in a field which is so rapidly making the hematological textbooks outdated. In this volume, thirteen in-depth reviews from large multicenter trials in the Federal Republic of Germany summarize the current state of diagnosis and management of leukemias. Childhood ALL and AML adult ALL and AUL were investigated. While cure appears to be achievable for more and more patients with acute leukemia, we still pursue the aim of optimal palliation in chronic leukemias. The management of patients with leukemia therefore varies to a large extent in aggressiveness of therapy. In some situations, rescue from an otherwise lethal disease is provided by bone marrow transplanta tion, which is discussed in two chapters."

Bone marrow transplantation, the goal which integrates hemato logists, immunologists, geneticists, oncologists and specialists of several other fields, has overcome its state of stagnation in recent years. Clinically as well as experimentally new approaches to old problems and new conclusions from recent findings proliferate: bone marrow transplantation in leukemic remission, bone marrow growth in cell culture, bone marrow manipulation with antisera, bone marrow differentiation in histoincompatible hosts, immuno suppression with partial body irradiation to cite just a few. These and other new developments were discussed by experts from 12 countries in and outside the European Community during an international seminar held on March 8-10, 1979 by the "Institut fur Hamatologie, GSF," under the auspices of the European Communities. The editors thank both the contributors to this symposium, who made it a successful meeting and submitted their manuscripts punctually, and the publishers, who have provided a volume of high quality in good time. They are also grateful for the valuable cooperation from numerous colleagues at the Institut fur Hamato logie."

This two-and-a-half-day symposium has concentrated on main aspects of the rapidly expanding field ofleukocyte markers in hematology. While leukemias are already being 'phenotyped' routinely in clinical centers, continued research on the developmental sta ge of cells and cell membranes, expanding into a malignant clone, permits new snap shots on hemopoietic differentiation. Thus the discovery of leukemia-associated anti gens, which so far have not been found on subpopulations of normal cells, has greatly stimulated the discussion on 'differentiation antigens versus tumor antigens'. The proceedings reflect the considerable success which has been achieved very re cently in the classification of hemoblastomas. Consequently the number of leukemias which are unclassifiable by immunological methods have dwindled down to a small mi nority. New facts give rise to new questions. By including the main points of the discussions in the proceedings, we wanted to give the reader an opportunity to get an impression of the questions and conclusions raised and drawn by the participants on the basis of new - and frequently still unpublished - data. The editors thank both the contributors to this symposium, who made it a successful meeting and submitted their manuscripts punctually, and the publishers, who have provided a volume of high quality in good time. They are also grateful for the valuable cooperation from numerous colleages at the Institut fUr Hamatologie.