Camrelizumab Plus Stereotactic Body Radiotherapy vs Camrelizumab Alone For Oligometastatic Nasopharyngeal Carcinoma

This study is testing whether adding targeted radiation (called stereotactic body radiotherapy, or SBRT) to an immunotherapy drug (camrelizumab) works better than immunotherapy alone for people with nasopharyngeal (throat/nasal) cancer that has spread to a small number of places in the body (called oligometastatic disease). **You may be eligible if...** - You are between 18 and 70 years old - You have nasopharyngeal cancer that has spread to no more than 5 spots total, with no more than 3 spots in any single organ - Your primary cancer site was already treated with radiation at least 3 months ago and is under control - You have already received at least one round of chemotherapy - You are generally in good health and able to carry out daily activities (ECOG 0 or 1) - Your cancer spots are small enough (brain spots under 3 cm, others under 5 cm) to be safely treated with SBRT - You have a life expectancy of more than 12 weeks **You may NOT be eligible if...** - A previous immunotherapy drug (like a PD-1 or CTLA-4 inhibitor) stopped working for you - You have a serious heart condition or irregular heartbeat - You have an active autoimmune disease (such as rheumatoid arthritis or inflammatory bowel disease) - You have active tuberculosis or HIV, or hepatitis B/C at certain levels - You are pregnant or breastfeeding - Your cancer is pressing on your spinal cord, or you need urgent brain surgery - You have taken high-dose steroids or immunosuppressants recently Talk to your doctor to see if this trial is right for you.