A Phase 0 Window of Opportunity Trial of Intratumoral Seasonal Influenza Immunization in Cutaneous Squamous Cell Carcinoma (CSCC) Patients Awaiting Curative Excision

This study is testing whether injecting the seasonal influenza (flu) vaccine directly into a skin squamous cell carcinoma tumor — a type of skin cancer — can trigger an immune response that helps fight the cancer before surgical removal. It is a short "window of opportunity" trial: participants receive the injection and then proceed to their planned cancer surgery. **You may be eligible if...** - You are 18 or older - You have been diagnosed with cutaneous squamous cell carcinoma (skin cancer) confirmed by biopsy - Your skin tumor is between 10 and 39 mm in its longest dimension - You are scheduled for Mohs surgery (a precise type of skin cancer removal) - You are generally in good enough health to participate **You may NOT be eligible if...** - Your skin tumor is smaller than 10 mm or larger than 39 mm - You are not a candidate for Mohs surgery - You are under 18 (this cancer type is extremely rare in children) - You have HIV with a detectable viral load, or uncontrolled hepatitis B or C Talk to your doctor to see if this trial is right for you.