Angelo Castello and Egesta Lopci * Pages 1 - 8 ( 8 )
Background: Immune checkpoint inhibitors (ICI) have achieved astonishing results and improved overall survival (OS) in several type of malignancies, including advanced melanoma. However, due to the peculiar type of anti-cancer activity provided by these drugs, the response patterns during ICI treatment can be completely different from that seen with “old” chemotherapeutic agents.
Objective: To provide an overview of the available literature and potentials of 18F-FDG PET/CT in advanced melanoma during the course of therapy with ICI in the context of treatment response evaluation.
Method: Morphologic criteria, expressed by Response Evaluation Criteria in Solid Tumors (RECIST), immune-related response criteria (irRC), irRECIST, and, more recently, immune-RECIST (iRECIST), along with response criteria based on metabolic parameters with 18F-Fluorodeoxyglucose (18F-FDG), have been explored.
Results: To overcome the limits of traditional response criteria, new metabolic response criteria have been introduced on time and are being continuously updated, such as the PET/CT Criteria for early prediction of Response to Immune checkpoint inhibitor Therapy (PECRIT), the PET Response Evaluation Criteria for Immunotherapy (PERCIMT), and “immunotherapy-modified” PET Response Criteria in Solid Tumors (imPERCIST). The introduction of new PET radiotracers, based on monoclonal antibodies combined with radioactive elements (“immune-PET”), appears of great interest.
Conclusion: Although the role of 18F-FDG PET/CT in malignant melanoma has been widely validated for detecting distant metastases and recurrences, evidences in course of ICI are still scarce and larger multicenter clinical trials are needed.
melanoma, 18F-FDG PET, response evaluation, immunotherapy, multicenter , malignancies
Nuclear Medicine; Humanitas Clinical and Research Hospital, Rozzano, Nuclear Medicine; Humanitas Clinical and Research Hospital, Rozzano