Prospective Study for the Prognostic and Predictive Role of Circulating Tumor Cells in Patients With Oropharyngeal Squamous Cell Carcinoma: CTCO (Circulating Tumor Cells in the Oropharynx)

"The collection and analysis of CTCs will be carried out in the following 6 steps: A blood sample will be taken: a maximum volume of 30 ml on 3 x 10 ml BD Vacutainer® EDTA tubes is required for the study.~CTCs will be enumerated and characterized by immunofluorescence after immunostaining with the following antibodies: anticytokeratin, anti-CD44, anti-N-cadherin and anti-PD-L1.~• - Secondary criterion(s) : Different tumor and clinical parameters will be analysed to find a correlation with CTC detection Gene expression profiles will be analyzed using the RNAseq single-cell at different times: before treatment, at interim times, and in case of relapse in order to establish correlations between patients at high risk of relapse and their molecular profiles"