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).