Abstract
BACKGROUND: Head and neck photoimmunotherapy specifically destroys tumor cells by irradiating them with 690 nm red light after administering cetuximab sarotalocan sodium. The key point in the technique of photoimmunotherapy is to set the irradiation area precisely with a margin added to the target lesion while securing a safety zone with large vessels such as the internal carotid artery. CASE REPORT: At our Institution, we performed photoimmunotherapy in combination with use of a navigation system on a male patient in his 70s with maxillary gingival carcinoma who had a recurrent lesion deep in the lateral pterygoid muscle. Three months after photoimmunotherapy, the superficial lesion had disappeared, the area of contrast within the lateral pterygoid muscle had improved, and the patient was deemed to have a complete response. CONCLUSION: The Navigation System was successfully used in combination with photoimmunotherapy. Additionally, this allowed the location of the internal carotid artery to be confirmed in real time.