Under Whole-course of Immunotherapy, Gradient Fractionated RT with CCT Versus CFRT with CCT for LANPC Who Achieved PR Post Induction Chemotherapy.

This study is comparing two radiation therapy approaches for patients with locally advanced nasopharyngeal cancer (cancer at the back of the nose/throat) who partially responded to initial chemotherapy plus immunotherapy. Both groups continue immunotherapy throughout. The question is whether using a gradual, varying dose schedule (gradient fractionated RT) is better than a standard dose schedule (conventional fractionated RT). **You may be eligible if...** - You have confirmed locally advanced nasopharyngeal carcinoma (stage III–IVA) - You achieved a partial response (shrinkage but not complete disappearance) after 3 cycles of platinum-based chemotherapy plus immunotherapy - You are between 18 and 65 years old - Your general health score (ECOG) is 0 or 1 and your organ function is adequate **You may NOT be eligible if...** - Your cancer did not respond to induction therapy - You have significant heart, liver, or kidney problems - You are pregnant or unwilling to use contraception Talk to your doctor to see if this trial is right for you.