• Patients with histologically or cytologically confirmed advanced NSCLC who require radiotherapy for metastatic lesions;

• At least one measurable lesion;

• Aged 18-70, regardless of gender;

• Disease progression after standard second-line therapy, and more than 2 weeks since the end of the last antitumor treatment;

• Expected survival of ≥3 months;

• ECOG performance status of 0-1;

• Female patients of childbearing age must have a negative pregnancy test and be able to take effective contraceptive measures with no plans for pregnancy within six months of the study;

• Able to undergo all screening period laboratory tests as required by the protocol;

• Normal major organ function, such as heart, liver, and kidney;

• Hematologic parameters: neutrophil count ≥1.5×10\^9/L, hemoglobin ≥10g/dL, platelet count ≥100×10\^9/L, total bilirubin ≤1.5 times the upper limit of normal, AST and ALT ≤2.5 times the upper limit of normal, creatinine and blood urea nitrogen ≤1.5 times the upper limit of normal, activated partial thromboplastin time ≤1.5×ULN, and International Normalized Ratio or prothrombin time ≤1.5×ULN;

• No active hepatitis, AIDS, syphilis, or other infectious diseases;

• Rheumatoid panel: C-reactive protein (CRP) ≤10.0mg/L; Anti-streptolysin O (ASO) \<500U; Erythrocyte sedimentation rate ≤15mm/h (men) or 20mm/h (women);

• Thyroid function tests: 0.27mIU/L ≤ Thyroid-stimulating hormone (TSH) ≤ 4.2mIU/L; 3.1pmol/L ≤ Free triiodothyronine (FT3) ≤ 6.8pmol/L; 12pmol/L ≤ Serum free thyroxine (FT4) ≤ 22pmol/L; 1.3nmol/L ≤ Serum total triiodothyronine (TT3) ≤ 3.1nmol/L; 66nmol/L ≤ Serum total thyroxine (TT4) ≤ 181nmol/L;

• Adrenocorticotropic hormone (ACTH): 1.1-17.6pmol/L;

• Ability to understand and voluntarily sign a written informed consent form.