The role of pulmonary metastasectomy for pulmonary metastasis from head and neck cancer.

The incidence rate of distant metastasis from head and neck (HN) cancers is 4.2-58.8%. The lung is the most common site of distant metastasis, and pulmonary metastasectomy (PM) can be performed in selected patients with pulmonary metastasis originating from HN cancers. However, due to the small number of study objectives, the knowledge on PM treatment of pulmonary metastasis from HN cancers remains insufficient, and the optimal management of pulmonary metastasis from HN cancer is unclear. Patients with pulmonary metastasis from HN cancer who underwent PM have a better prognosis than those who did not, with reported 5-year overall survival rates after PM of 20.9-59.4%. A histology of squamous cell carcinoma, incomplete resection, a short disease-free interval (DFI), and the oral cancer have been identified as factors predicting a worse prognosis after PM in this patient population. As a systemic therapy, longer overall survival has been achieved using immune check point inhibitors compared with standard single-agent therapies. Since the clinical and morphological diagnoses of pulmonary metastasis from HN cancers are often difficult, molecular techniques can provide useful information for the differential diagnosis between pulmonary metastasis from HN cancers and primary lung cancers. In cases of suspected pulmonary metastasis from HN cancer, the surgical strategy should be determined based on the patient's clinical background.