A prospective, proof-of-concept pilot study in patients with metastatic cancers (9 types of cancers are studied) treated at the IUCT-O or possibly in other institutions. Eligible patients will be selected and informed of this study during a medical consultation for their cancer by medical oncologists. Then, with the patient's consent and before the start of anti-cancer treatment (whatever the line), a blood sample will be taken to detect DP-circulating cells by 2 different methods of analysis.

Each patient will participate in the study for one day. The methods of analysis will be: flow cytometry for all patients and either Parsotix® or CellSearch® depending on the type of cancer.

450 patients will be enrolled in total.

Inclusion Criteria:

• 1. Patients with one of the following cancer types: urothelial carcinoma, renal carcinoma, prostate adenocarcinoma, upper aerodigestive tract carcinoma, cervival carcinoma, adenocarcinoma of endometrium, cutaneous melanoma, soft tissue sarcoma, seminomatous and nonseminomatous germ cell tumors
• 2. Metastatic disease for which the treatment (whatever the line) has not been initiated yet
• 3. Age ≥ 18 years
• 4. Patient affiliated to a French Social Security scheme
• 5. Patient having signed his/her informed consent prior to inclusion in the study and prior to any specific procedure for the study.

Exclusion Criteria:

• 1. Patient with localized disease.
• 2. Pregnant or breast-feeding women.
• 3. Any psychological, family, geographical or sociological condition that prevents compliance with the medical monitoring and/or procedures set out in the study protocol.
• 4. Patient who has forfeited his/her freedom by administrative or legal award or who is under legal protection (curatorship and guardianship, protection of justice).