• Age≥ 18 years.

• Histology or cytology confirmed nasopharyngeal carcinoma.

• Metastatic nasopharyngeal carcinoma of bone that is not suitable for local or radical therapy.

• Distant bone metastases confirmed by imaging (two images) or pathology (plus one image) (AJCC 8th, stage IVB), except for isolated local invasion of the base bone of the skull.

• With or without metastases from other organs, but lesions may be non-measurable distant organ metastases or lymph node lesions (as assessed by RECIST 1.1).

• Bone metastases may contain soft tissue components of osteolytic lesions.

• Patients have not previously received systemic therapy for advanced or metastatic disease, and prior induction chemotherapy, concurrent chemoradiotherapy, or adjuvant chemotherapy must have been completed more than 6 months prior to enrollment. Previous radiotherapy or concurrent chemoradiotherapy should also be completed more than 6 months prior to enrollment.

• Expected survival ≥ 3 months.

• According to the Eastern Cooperative Oncology Group (ECOG) criteria, the performance status score is 0 or 1.

⁃ Good organ function:Hemoglobin \> 8.0 g/dl; Absolute neutrophil count (ANC) \>1,500/mm3; Platelet count\> 100,000/μl; Total bilirubin ≤ 1.5 times the upper limit of normal (ULN); Alanine aminotransferase and glutamate aminotransferase \< 2.5 ULN (upper limit of normal), (alanine aminotransferase and aspartate aminotransferase \< 5 ULN in patients with liver metastases), alkaline phosphatase\< 4 ULN;Prothrombin time (PT) international normalized ratio/prothrombin time (PTT) \< 1.5 ULN, serum muscle；Anhydride\< 1.5ULN.

⁃ Willing and able to comply with planned visits, treatment plans, laboratory tests, and other research procedures.