Translational relevance of liquid biopsy approaches in advanced melanoma

of five patients treated with anti-PD-1 as first line treatment. Our results, although still exploratory, suggest the predictive potential of baseline testing of circulating miR-155-5p as biomarker of response to immunotherapy. With the aim of enhance melanoma CTCs detection we tested the feasibility of the microfluidic system EPISPOT in a DROP (EPIDROP). Using the EPIDROP assay, we developed a panel of markers specific for melanoma CTCs (MCAM, MCSP, MART-1). The 6 use of this panel could improve the identification of CTCs in melanoma patients, thus providing better prognostic information. Finally, we provided a comprehensive analysis of ccfDNA mutations in a metastatic patient who had an exceptional response to immunotherapy. We found several mutated genes associated with response to immunotherapy. In conclusion, we demonstrated the feasibility and usefulness of liquid biopsy in the personalized management of advanced melanoma patients who experience relapse and develop resistance to immunotherapy.