This study is a retrospective real-world study. In this study, we plan to collect the clinical data of lung metastatic nasopharyngeal carcinoma patients who received PD-1 inhibitors and chemotherapy combined with or without radiotherapy.

Inclusion Criteria:

1. age of at least 18 years;
2. Karnofsky Performance Status (KPS) ≥60;
3. histologically confirmed nasopharyngeal squamous carcinoma;
4. metastatic disease after primary standard treatment (patients who had metastatic diseases over six months after treatment);
5. at least 1 measurable metastatic lesions in lung or mediastinal or pleura (imaging for distant metastases with FDG-PET/CT or chest/abdomen CT with contrast);
6. adequate renal , liver and bone marrow function.

Exclusion Criteria:

1. previous treatment with an immune checkpoint inhibitor;
2. recurrent disease;
3. previous systemic chemotherapy for metastatic disease;
4. symptomatic central nervous system metastases;
5. a history of non-infectious pneumonitis that required glucocorticoids, or active autoimmune disease;
6. severe organ dysfunction or not suitable for chemoradiotherapy;
7. individuals that had serious kidney, heart, blood, nervous system, or liver diseases or psychiatric disorders;
8. individuals that had taken part in any other clinical trials testing other drugs within 3 months of the present study;
9. other patients whom researchers deemed unsuitable to participate in the study.