Lihong Bu*, Yanqiu Sun*, Guang Han*, Ning Tu, Jiachao Xiao and Qi Wang Pages 675 - 687 ( 13 )
Cancer immunotherapy (also known as immuno-oncology), a promising anti-cancer strategy by harnessing the body’s own immune system against cancer, has emerged as the “fifth therapeutic pilla” in the field of cancer treatment since surgery, chemotherapy, radiation and targeted therapy. Clinical efficacy of several immunotherapies has been demonstrated in clinical settings, however, only a small subset of patients exhibit dramatic or durable responses, with the highest reported frequency about 10-40% from single-agent PD-L1/PD-1 inhibitors, suggesting the urgent need of consistent objective response biomarkers for monitoring therapeutic response accurately, predicting therapeutic efficacy and selecting responders. Key elements of therapeutic responses to cancer immunotherapies contain the cancer cell response and the alternation of inherent immunological characteristics.
Here, we document the literature regarding imaging the key elements of therapeutic responses to cancer immunotherapies using PET. We discussed PET imaging approaches according to different response mechanisms underlying diverse immune-therapeutic categories, and also highlight the ongoing efforts to identify novel immunotherapeutic PET imaging biomarkers. In this article, we show that PET imaging of the key elements of therapeutic responses to cancer immunotherapies using PET can allow for more precise prediction, earlier therapy response monitoring, and improved management. However, all of these strategies need more preclinical study and clinical validation before further development as imaging indicators of the immune response.
Positron emission tomography, cancer immunotherapy, therapy response, immune checkpoint blockade, adoptive T cell therapy, tumor vaccine, cytokine.
PET-CT/MRI Center, Faculty of Radiology and Nuclear Medicine, Wuhan University Renmin Hospital, Wuhan, Hubei, Department of Radiology, Qinghai Provincial People's Hospital, Xining, Qinghai, Department of Radiation Oncology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PET-CT/MRI Center, Faculty of Radiology and Nuclear Medicine, Wuhan University Renmin Hospital, Wuhan, Hubei, PET-CT/MRI Center, Faculty of Radiology and Nuclear Medicine, Wuhan University Renmin Hospital, Wuhan, Hubei, The 1st Department of Gastrointestinal Surgery, Wuhan University Renmin Hospital, Wuhan, Hubei