Lymphoscintigraphy Directed Elective Neck Radiation for p16+ Favorable Risk Oropharynx Cancer

This study is exploring whether a lymph node mapping technique (lymphoscintigraphy) can help doctors better target radiation to only the necessary lymph nodes in the neck — potentially sparing patients with p16-positive throat (oropharyngeal) cancer from unnecessary radiation to both sides of the neck. **You may be eligible if:** - You have been diagnosed with squamous cell carcinoma of the throat (oropharynx), confirmed by biopsy - Your cancer tests positive for p16 (a marker associated with HPV-related cancer) - Based on imaging, cancer has not spread to lymph nodes on both sides of the neck - You are planned to receive radiation to both sides of the neck per standard guidelines - Your tumor is Stage T1 or T2 and is near but does not clearly cross the midline of the throat - You have recent CT/MRI and PET/CT imaging available **You may NOT be eligible if:** - Cancer is found in lymph nodes on both sides of the neck - Your cancer is not p16-positive - Your disease cannot be measured accurately on imaging Talk to your doctor to see if this trial is right for you.