Therapeutic Drug Monitoring of BRAF-mutated Advanced Melanoma

Inclusion Criteria: * Men and women 18 years of age and older * Histologic proven advanced skin melanoma (Stage IV or stage IIIc inoperable) with BRAF V600 mutation * Patient who will treated with combined kinase inhibitors (dabrafenib + trametinib). * Patient able to stand a blood collection of 20 mL * Ability to provide an informed written consent form * Patient must be affiliated to a social security system * Patient's legal capacity to consent to study participation and to understand and comply with the requirements of the study. Exclusion Criteria: * Patient with mucosal melanoma * Patient with non-metastatic skin melanoma (All stages except stage IV and stage III C inoperable) * Patient with another synchronous cancer, or within 3 years * Patient with a contraindication to blood collection of 20 mL * Patient deprived of liberty or under supervision * Patient unable to receive kinase inhibitor therapy * Patient treated with another combined kinase inhibitors than dabrafenib and trametinib * Pregnant or breastfeeding women * Patient (man or woman) of childbearing age who does not agree to use of contraceptive methods validated during the study