Tislelizumab Combined With Chemotherapy in the Treatment of Bone Metastases of Unknown Primary

Inclusion criteria

• ✓. Willing and able to provide written informed consent/consent for the trial.
• ✓. Be at least 18 years old on the day of signing the informed consent.
• ✓. Patients with bone metastases from cancer of unknown primary (BMCUP) diagnosed according to the criteria defined in the clinical practice guidelines of the European Society of Medical Oncology (ESMO) in 2015 and confirmed by imaging and histology to have bone metastases that cannot be completely resected.
• ✓. Did not receive systemic treatment.
• ✓. Have at least one measurable lesion according to RECIST1.1, willing to agree to archived tumor (in formalin fixed paraffin-embedded (FFPE) block) or fresh tumor material (cryogenic refrigerator or liquid nitrogen storage).
• ✓. ECOG performance level 0 or 1 point.
• ✓. The expected survival time is ≥3 months.
• ✓. Adequate organ and bone marrow functions (all screening tests should be performed within 10 days of the start of treatment) :A) Absolute neutrophil count ≥1.5x109 /L.B) Platelet ≥100x109 /L.C) Hemoglobin ≥9g/dL(≥90g/L).D) No blood transfusion or erythropoietin dependence (within 7 days of evaluation).E) Serum creatinine ≤1.5x upper normal limit (ULN) or creatinine level \> 1.5xULn, creatinine clearance ≥60 ml/min (creatinine clearance should be calculated according to institutional criteria).F) Patients with serum total bilirubin ≤1.5xULN or total bilirubin level \> 1.5ULN, direct bilirubin ≤ULN.G) Aspartate aminotransferase ≤2.5xULN(if liver metastasis is present).H) Alanine aminotransferase ≤2.5xULN(if liver metastasis is present).I) Albumin ≥2.5g/dL.J) International standardized ratio (INR) or prothrombin time ≤1.5xULN(if subject is being treated with anticoagulant, prothrombin time or partial prothrombin time should be within the range expected for treatment with anticoagulant).K) Activated partial thrombin time ≤1.5xULN(prothrombin time or partial prothrombin time should be within the expected therapeutic range of anticoagulant use).L) Women with reproductive potential should undergo a mandatory serum-negative pregnancy within 72 hours prior to receiving the first dose of the study drug.M) Fertile female subjects must be willing to use appropriate contraceptive methods during the study up to 120 days after the last use of the study drug.Note: Abstinence is acceptable if this is the subject's usual lifestyle and preferred method of contraception.N) Male subjects with reproductive potential must consent to use appropriate contraceptive methods from the first study treatment until 120 days after the last study treatment.