Immunotherapy With Chemotherapy and Chemoradiation for Advanced Squamous Cancer of Nasal Cavity / Paranasal Sinuses (I-NAPA)

This trial (I-NAPA) tests adding immunotherapy to the standard chemotherapy and radiation treatment for squamous cell cancer of the nasal cavity and sinuses that is at an advanced stage. The goal is to improve response rates and survival in a cancer type with limited treatment options. **You may be eligible if...** - You are 18 or older - You have a new diagnosis of Stage II–IVb squamous cell carcinoma of the nasal cavity or paranasal sinuses - You have not received any prior treatment for this cancer - You are in generally good health and have measurable disease on imaging - You are willing to use contraception during and after treatment **You may NOT be eligible if...** - You have received prior treatment for this cancer - You have active autoimmune disease or certain other serious conditions - You are pregnant or breastfeeding - Your organ function does not meet requirements Talk to your doctor to see if this trial is right for you.