Chapter 9 - Hematologic Malignancies

Abstract

An immune-centered approach, best exemplified by the use of various monoclonal antibodies and allogeneic hematopoietic cell transplantation, has long been part of the treatment paradigm of many hematologic malignancies. In recent years, our understanding of tumor biology, the role of the tumor microenvironment, and the mechanisms that malignant cells exploit to avoid immune detection has dramatically progressed. This has led to the advent of promising treatment approaches including various types of immune checkpoint inhibitors, cellular therapies, vaccines, costimulatory receptor agonists, and immunomodulatory agents. Based on their impressive efficacy in certain solid tumors, the immune checkpoint inhibitors have been evaluated in various hematologic malignancies. Hodgkin lymphoma, through its genetically determined dependence on the checkpoint pathway for immune evasion, served as a model for this approach. This has indeed shown striking results in the treatment of patients with relapsed or refractory disease. Emerging data also show that the immune checkpoint inhibitors, alone or in combination with targeted therapies or other modalities of immunotherapies, might have promising roles in other types of hematologic malignancies.