T1 T2 and T3 OSCC tumor, patients who have a recent evaluation cervico thoracic scanner in their medical files.

We will analyse the pre operative scannographic and MRI (if available) images, and the post operative pathological analyses.

The scanners will be reviewed by 2 well trained clinicians (one head and neck radiologist and one head and neck surgeon).

Then we will analyse the correlation between the radiological and the pathological analysis.

With a Bland Altman analysis we will assess the good correlation between the pre and post operatory mesures of the depth of invasion in the oral squamous cell carcioma