SBRT and LDRT Combined With PD-1 Antibody and Chemotherapy in r/m Nasopharyngeal Carcinoma

This study is testing a combination of radiation therapies — targeted high-dose radiation (SBRT) to specific tumors and low-dose radiation (LDRT) to other sites — together with an immunotherapy drug (anti-PD-1 antibody) and chemotherapy for people with nasopharyngeal cancer (a cancer in the back of the nose and throat) that has come back or spread. **You may be eligible if:** - You have been diagnosed with recurrent or metastatic nasopharyngeal cancer (WHO type II or III) - You have not yet received any treatment for the recurrent or metastatic disease - Your physical fitness score (ECOG) is 0 or 1 - At least one tumor can safely receive targeted high-dose radiation - Your blood counts, liver, and kidney function are within acceptable ranges - You are willing to use effective contraception during and 3 months after treatment **You may NOT be eligible if:** - You have already received radiation, chemotherapy, or immunotherapy for this recurrence - You have a contraindication to immunotherapy or radiation - Your blood counts or organ function are too low Talk to your doctor to see if this trial is right for you.