Personalized Circulating DNA Follow-up in Melanoma (PERCIMEL)

Inclusion Criteria: * Adult patient; * ECOG performance status 0-2; * Patient with melanoma stage IIB or IIC, or any stage III, or stage IV that has been resected or is resectable; * Treatment-naïve patient (except for initial excisional biopsy performed for diagnostic purposes); * Patient scheduled to receive adjuvant therapy within 12 weeks following surgery, consisting of anti-BRAF and anti-MEK kinase inhibitors or anti-PD-1 monoclonal antibody immunotherapy, in accordance with marketing authorization; * Patient with stage IIIB, IIIC, IIID, or IV melanoma with macroscopic lesions (clinically or radiologically detectable) eligible for neoadjuvant therapy, surgery, and adjuvant therapy (according to current recommendations: ESMO and NCCN guidelines, and treatment regimens from the SWOG S1801 and NADINA studies); * Biological parameters compatible with the planned treatment; * Patient informed and having provided written informed consent. Exclusion Criteria: * Patient with mucosal melanoma or choroidal (uveal) melanoma; * Patient with another synchronous malignancy or who has been treated for another malignancy within the 3 years preceding informed consent (except carcinoma in situ of the cervix or resected cutaneous carcinoma); * Contraindication to a 30 mL blood sample; * Contraindication to surgery; * Contraindication to the proposed medical treatment (anti-BRAF and anti-MEK targeted therapies or immunotherapy); * Patient participating in another clinical trial involving an investigational medicinal product; * Pregnant or breastfeeding woman; * Patient deprived of liberty (including those under legal guardianship or curatorship).