Preoperative Immunotherapy in Patients With Squamous Cell Carcinoma of the Head and Neck

This trial is studying whether giving a single dose of an immune checkpoint drug (pembrolizumab) before surgery — a strategy called neoadjuvant immunotherapy — helps prime the immune system to better fight head and neck squamous cell carcinoma (cancer of the mouth, throat, and related areas), by analyzing how the tumor changes between biopsy and surgical removal. **You may be eligible if...** - You are 18 or older - You have been diagnosed with head and neck squamous cell carcinoma (SCCHN) that is planned for surgical removal - Your cancer has not yet been treated - You are well enough to carry out daily activities (ECOG 0 or 1) - Your blood counts and organ function meet minimum thresholds - A tumor biopsy sample is available (or you agree to have one taken) **You may NOT be eligible if...** - You have an active autoimmune disease that requires immune-suppressing treatment - You have received prior treatment for this head and neck cancer - You are on steroids or other immune-suppressing medications - You are pregnant or breastfeeding - You have a history of severe immune-related reactions to prior immunotherapy Talk to your doctor to see if this trial is right for you.