cDNA and Residual Disease After Chemoradiotherapy for Locally Advanced Head and Neck Squamous Cell Carcinomas

cDNA detection and objective response one month after the end of chemoradiotherapy

The detection or non detection of cDNA after treatment will be compared with the objective response (complete response versus progression/stability/partial response)

Time frame: 1 month after the end of chemoradiotherapy

Overall survival

The overall survival is defined as the time between the date of inclusion and the date of death from any cause.

Time frame: At the end of the main study (27 months after the end of treatment)

Progression-free survival

The progression-free survival is defined as the time between the date of inclusion and the date of the first progression of the disease (clinical or radiological) or death from any cause.

Time frame: At the end of the main study (27 months after the end of treatment)

cDNA kinetic

cDNA detection at 1 and 3 months after the end of chemoradiotherapy

Time frame: 1- and 3-month after the end of chemoradiotherapy

Concordance of mutational profiles and HPV-HR genotypes between primary tumor, ctDNA at diagnosis and ctDNA

This will be evaluated according to the mutational profile determined by NGS at each timepoint

Time frame: 1- and 3-months after the end of chemoradiotherapy

Determining the most frequent mutations.

That will be evaluated by analysing the results of NGS (among the 194 genes in our panel)

Time frame: 3-months after the end of chemoradiotherapy