Post Operative Adjuvant Therapy De-intensification Trial for Human Papillomavirus-related, p16+ Oropharynx Cancer

This clinical trial studies the intensity of adjuvant ("helper") therapy required in p16 positive oropharynx cancer patients, who have had all known disease removed surgically by a minimally invasive approach, and who have extracapsular spread in their lymph nodes. Patients can consent to participate in either the randomized (physician chooses radiotherapy arm or radiotherapy \& cisplatin arm) or non-randomized (patient chooses radiotherapy arm or radiotherapy \& cisplatin arm) pathways. After the surgery, receive either radiation alone, or radiation and weekly cis-platinum during therapy. Patients are then followed for cancer, functional and quality of life outcomes.