BACKGROUND: A considerable proportion of metastatic melanoma (mM) patients do not respond to immune checkpoint inhibitors (ICIs). There is a great need to develop noninvasive biomarkers to detect patients, who do not respond to ICIs early during the course of treatment. The aim of this study was to evaluate the role of early [ PATIENTS AND METHODS: . In this prospective noninterventional clinical study, mM patients receiving ICIs regularly underwent RESULTS: Overall, 71 patients were included. The median follow-up was 37.1 months (952% CI = 30.1-38.0). Three (4%) patients had only baseline scans due to rapid disease progression and death prior to W4 CONCLUSIONS: Evaluation of mM patients with early