The purpose of this study is to evaluate the diagnostic performance of 18F-FDG micro-PET-CT in malignant Head and neck cancer compared to definitive histological analysis (gold standard).

In approximately 20% of cases, surgical margins are considered insufficient. The only tool currently available intraoperatively to assess the quality of surgical resection is the extemporaneous examination. This has a sensitivity of only 10%.

The objective is therefore to evaluate the performance of another tool, available intraoperatively, to help surgeons assess the quality of their resection. Currently, micro-PET-CT allows for the evaluation of surgical specimens (CE marking and FDA approval obtained). Its performance in the evaluation of surgical margins remains to be demonstrated. This is the subject of the present study.

Inclusion Criteria:

• Signed informed consent
• Adult, male or female, aged 18 or over
• Patient with a malignant tumor of the oral cavity, oropharynx, hypopharynx, larynx, sinuses, or salivary glands, regardless of lymph node status (any N) M0, operable
• Member or beneficiary of a social security plan

Exclusion Criteria:

• Child-Pugh C liver failure
• Patients under guardianship, conservatorship, or legal protection
• Patients deprived of their liberty
• Pregnant or breastfeeding women
• Hypersensitivity to 18F-FDG or any of its excipients (ethanol or water for injection)
• Uncontrolled diabetes
• Moderate to end-stage renal failure, stage IIIB to V (glomerular filtration rate less than 44 mL/min/1.73 m²)
• Patients unable to understand the study for any reason or to comply with the trial requirements (language, psychological, or geographical issues).