Metastatic tumors in the oral and maxillofacial region: A multicenter retrospective investigation in Japan

Background/purpose Metastatic tumors in the oral and maxillofacial region are rare. The purpose of this study was to investigate the incidence and prognosis of this entity based on a multicenter retrospective analysis. Materials and methods The medical records of patients with metastatic tumors to the oral and maxillofacial region were retrospectively reviewed, and 81 patients with such metastatic tumors were included in this study. The incidence and prognosis of the patients were investigated as endpoints of this study. Results The male to female ratio was 1.8 to 1. The patients’ mean age was 67.4±12.4 years old. The most common primary site was the lungs (25.9%). As for the metastatic sites in the oral and maxillofacial region, the most common site was the lower gingiva (35.8%). Adenocarcinoma was the most common diagnosis (37.0%). The administration of molecular targeted drugs and immune checkpoint inhibitors (ICIs) showed the tendency of better control compared with the non-administration of these drugs. The local resection of the metastatic tumor resulted in significantly better metastatic lesion control than other treatments (HR: 0.259, 95%CI: 0.103-0.650 P