Pain Management With Pecfent in the Prevention of Pain Induced by Position in Radiotherapy

Participation to the trial will be proposed to the patient by the investigator in charge of the analgesic irradiation during the preliminary scanner session that will be held before radiotherapy session(s). Patients with a VAS≤ 3 will be excluded. PecFent and Placebo will be delivered by Archimedes Pharma When starting the radiotherapy session(s) (2 days after the preliminary scanner session), the medic will collect the patient signed informed consent, will deliver the treatment 1 dose of fentanyl transmucosal (Pecfent® ) 100µg in naive patients or 1 dose of Pecfent® 200µg in patient with a stable opioid background pain treatment or placebo) and will collect pain intensity value with a patient VAS collected before and at the end of the radiotherapy session. Finally patient \& radiotherapists global satisfaction will be collected An assessment a week the end of the radiotherapy session will be assessed by investigator consisting in a Patient global satisfaction Study follow up: Patients will receive a phone call a week after the radiotherapy session to collect patient global satisfaction score related with the global management of the radiotherapy session