This book focuses on the latest progress in chemotherapy for leukemia and related diseases, including still-ongoing but promising studies. The effectiveness of treatment for chronic myeloid leukemia and acute promyelocytic leukemia has been dramatically improved in recent years. This improvement has been made possible with the development of molecular targeted agents such as bcr-abl tyrosine kinase inhibitors and all-trans retinoic acid. The antibody for the unique target of chemokine receptor 4 for adult T-cell leukemia/lymphoma, or FLT3 inhibitors (signaling inhibitors) has been applied to other leukemias.