Twenty years ago when Children's Cancer Association of Japan was born, the diagnosis of childhood leukemia amounted to a death sentence. Only 20% or so of children with leukemia survived more than 5 years. Since then, enormous improvements have been achieved regarding our understanding on the etiology, diagnosis, and the treatment of childhood leukemia. Now, 70% of children with leukemia survive and enter adult life. Even though the improved survival rate of children with leukemia represents a medical success story, we now face new problems. The first problem is the fact that we still lose 20-30% of patients with childhood leukemia. To address this problem, we need to understand the etiology, epidemiology, and biology of leukemia; to identify the patients at greater risk; and to develop adequate treatments. The second problem is the treatment itself. Even though efficacious, the modem treatment for leukemia is a grueling experience for children and their families. We should develop a total care system for families and children based on a deep understanding of their needs. The third problem is the aftereffects of the treatment and of cured leukemia. Extensive radiation and chemotherapy have an entirely different spectrum of long-term effects on children than on adults. These treatments in the early stage of life, when the mind and body are developing, create many physical and psychological problems. These are the present problems of childhood leukemia.

I. Biology of Childhood Leukemia.- 1. Etiological mechanisms in childhood acute lymphoblastic leukemia.- 2. The effects of hemopoietic factors on stem cells in vitro.- 3. Bone marrow stromal cells and hematopoiesis.- 4. Gene transfer investigations of oncogenes activated by chromosomal translocations in human lymphomas and leukemias: BCL2 and C-MYC.- 5. Molecular studies of chromosomal translocations in childhood leukemias.- 6. Molecular analysis of chromosomal abnormalities in childhood acute lymphoblastic leukemia.- 7. Immunological properties of hemotopoietic malignancies in childhood.- 8. Polymerase chain reaction studies on chronic myelogenous leukemias and detection of residual Phi1 clone after bone marrow transplantation.- 9. Lineage-specific classification of childhood leukemia and its clinical implications.- II. Epidemiology of Childhood Leukemia.- 10. The epidemiology of leukemia: Results from the Manchester Children's Tumour Registry.- 11. Contribution of Japan Children's Cancer Registry to medical research and care of childhood leukemia and related conditions.- 12. Long-term survivors of leukemia and late effects: A report from the Registry of Long-Term Survivors of Children's Cancer of Japan.- III. Treatment of Childhood Leukemia.- 13. Therapy of childhood leukemia: Understanding success and failure.- 14. Results and significance of six randomized trials in four consecutive ALL-BFM studies.- 15. Pharmacokinetics of commonly used anti-leukemic agents in children.- 16. Treatment of acute nonlymphoblastic leukemia in the Children's Cancer and Leukemia Study Group.- 17. Treatment of childhood acute lymphoblastic leukemia: The results of the Tokyo Children's Cancer Study Group L84-11 treatment protocol study.- 18. Bone marrow transplantation inchildren and adolescents with leukemia.- 19. Bone marrow transplantation in children and quality of life in long-term survivors.- 20. Autologous bone marrow transplantation for children with leukemia.- 21. Peripheral blood stem cell autografts in children with acute leukemia and lymphoma.- 22. Varied problems associated with immunocompromised hosts.- IV. The Total Care and the Patient Support System for Children with Leukemia.- 23. Activities of the Children's Cancer Association of Japan.- 24. Candlelighters: Parents and caregivers, friends and allies, working together for life.- 25. Who helps families of children with cancer? Parent and patient support in the U.K..- 26. The Ronald McDonald House program in the United States.- 27. Total care of the child with cancer.- 28. Home care for children with cancer.