Detection of Circulating Tumor DNA in p16- Locally Advanced Head Neck Squamous Cell Carcinoma

Locally advanced head and neck squamous cell carcinoma (LAHNSCC) is a heterogeneous disease, associated with a poor prognosis and no improvement in overall survival for years. Furthermore, treatments (surgery, radiotherapy, chemotherapy) are frequently associated with acute and late toxicities. Beside p16/HPV + tumors, only TNM classification can help estimating the prognosis of the patients. A better evaluation of the prognosis and of the risk of metastatic spread would help defining the best treatment.

Circulating tumor DNA (ctDNA) has been reported as both a prognostic factor and a non-invasive way to assess tumor relapse in several cancer types. Few data are available in HNSCC, and no data among p16/HPV- cancers. Indeed, ctDNA assessment is usually based on tumor mutation monitoring. But if recurrent mutations are frequent in several cancers types (PIK3CA, KRAS, ESR1, TERT…), there is no recurrent mutation observed in HNSCC. Thus ctDNA assessment in LAHNSCC must be performed after the identification of a tumor specific mutation for each patient.

In that context, the aim of this study is to perform a molecular analysis of primary LAHNSCC, and to look for the amount of ctDNA before surgery, after surgery, and during 18 months of follow up.