Several studies conducted over the past decade have shown that Circulating tumor cells (CTCs) can be used as a marker for predicting disease progression and survival in patients with early or metastatic cancer. A high number of CTCs correlate with aggressive disease, increased metastasis and decreased survival rates.

Knowledge of metastasis mechanisms was mainly obtained from mouse models with CTCs after orthotopic transplants. The only possibility to study the patient's CTC subpopulations is to carry out ex-vivo expansion and develop an animal model with CTC xenograft. Because circulating blood collection is simple and non-invasive, CTCs can be used as a marker to track disease progression and survival in real time. CTCs could also guide therapeutic choice.

COHORT 1

Inclusion Criteria:

• Histologically confirmed cutaneous or mucosal melanoma (per American joint committee on cancer (AJCC) staging system) that is unresectable or metastatic
• No prior systemic anticancer therapy for unresectable/metastatic melanoma or clinical/radiological disease progression (RECIST1.1) if previously treated and before new treatment
• No prior malignancy active within the previous 3 years except for locally curable cancers that have been apparently cured, such as cutaneous carcinoma or cervix)
• followed in Saint Louis Hospital
• Tumor tissue available in Saint Louis Hospital
• Subjects must have signed and approved written informed consent form
• No pregnancy
• Any positive test for hepatitis A virus, hepatitis B virus or hepatitis C virus indicating acute or chronic infection, and/or detectable virus

Exclusion Criteria:

• None

COHORT 2 :

Inclusion Criteria :

• Histologically confirmed cutaneous or mucosal melanoma
• Candidates for sentinel lymph node analysis and surgical recovery (this examination is in practice reserved for melanomas >1mm thick or ulcerated)
• No prior adjuvant anticancer therapy
• followed in Saint Louis Hospital
• Tumor tissue available in Saint Louis Hospital
• Subjects must have signed and approved written informed consent form
• No pregnancy
• Any positive test for hepatitis A virus, hepatitis B virus or hepatitis C virus indicating acute or chronic infection, and/or detectable virus

Exclusion Criteria:

• None

Cohort1: Cohort of patients with stage III unresectable or IV metastatic melanoma patients Cohort 2: Cohort of patients with melanoma candidates for sentinel lymph node analysis