Study to Evaluate the Interest of Qutenza in Patients With Head and Neck Cancer in Remission and With Sequelae Neuropathic Pain.

This study aims to compare the analgesic activity of capsaicin patch 8% applications at 3 months interval each on the cervico-facial area versus a reference neuropathic treatment with amitriptyline in patients with head and neck cancer in remission and with sequelae neuropathic pain. In this phase II trial, patients will be assigned in one of the two treatment arms: * Arm A (Experimental arm): Capsaïcin patch (Qutenza®) * Arm B (standard arm): Amitriptyline (Laroxyl®) 130 patients will be included and will be followed during 9 months.