ABSTRACT
Immunotherapy, which has been increasingly used in cancer treatment in recent years, has led to groundbreaking developments. Immune checkpoint inhibitors, new monoclonal antibodies for immunotherapy, have totally changed clinical approaches and revealed very unique patterns in medical imaging. The importance of positron emission tomography/ computerized tomography (PET/CT), which allows the metabolic and morphological evaluation of the whole body, has increased for the early and accurate evaluation of both the immunological response and side effects. The use of existing response criteria may be misleading due to immune-related inflammation, and new approaches of assessing are needed. In this review, the role of PET/CT in evaluating immunotherapy response and potential solutions to emerging problems are discussed.
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