Affiliations: [a] Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Italy | [b] Division of Pathology, Department of Health Sciences (DSS), University of Florence, Italy | [c] Division of Dermatology, Department of Health Sciences (DSS), University of Florence, Italy
Correspondence:
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Corresponding author: Pamela Pinzani, Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, viale Pieraccini 6 50139 Firenze, Italy. Tel.: +39 055 275 8233; E-mail: p.pinzani@dfc.unifi.it.
Abstract: BACKGROUND: Circulating tumor cells (CTCs) and circulating cell free DNA (ccfDNA) represent a liquid biopsy of a tumor allowing real time disease monitoring especially in advanced stages of cancer, but their analysis is technically challenging. OBJECTIVE: We aimed to demonstrate the feasibility of two different technical approaches to detect the BRAFV600E mutation in the liquid biopsy of 20 metastatic melanoma patients by using both the enriched CTC fraction and circulating ccfDNA from the same blood sample. METHODS: We detected CTCs by a filtration method in 20 metastatic melanoma patients and detected the BRAFV600E variant on CTCs and ccfDNA by an allele-specific qPCR assay; the mutated samples were confirmed by ICE-COLD PCR followed by Sanger sequencing. RESULTS: We found CTCs in 70% of the samples, and identified the BRAFV600E variant on CTCs. We correlated the results with those obtained on ccfDNA from the same blood draw. We found some discordant results between CTCs and ccfDNA. CONCLUSIONS: Our results underline the importance of investigating both CTCs and ccfDNA in a liquid biopsy approach to melanoma patients.
