Inclusion Criteria:

          -  Patients must have FDG-avid and histologically or cytologically proven squamous cell
             carcinoma of the oropharynx (tonsil, base of tongue, oropharyngeal wall, soft palate)
             that is p16 positive by immunohistochemistry or HPV positive by in situ hybridization.

          -  AJCC eighth edition staging stage 1 and stage 2

          -  Appropriate stage for protocol entry, including no distant metastases, based upon the
             following minimum diagnostic workup:

          -  History/physical examination, including documentation of weight within 4 weeks prior
             to registration;

          -  FDG-PET/CT scan for staging and RT plan within 4 weeks prior to registration;

          -  Zubrod Performance Status (A quantification of the functional status of cancer
             patients that runs from 0 to 5, with 0 denoting perfect health and 5 death) 0-1 within
             4 weeks prior to registration;

          -  Age ≥ 18;

          -  Able to tolerate PET/CT imaging required to be performed

          -  CBC/differential obtained within 4 weeks prior to registration on study, with adequate
             bone marrow function;

          -  Serum creatinine within normal institutional limits or a creatinine clearance ≥ 45
             ml/min within 4 weeks prior to registration;

          -  Women of childbearing potential and male participants must agree to use a medically
             effective means of birth control throughout their participation in the treatment phase
             of the study.

          -  The patient must provide study-specific informed consent prior to study entry.

        Exclusion Criteria:

          -  cT4, cN3 or cM1 disease

          -  "Matted nodes" as determined by review with Neuroradiology

          -  Gross total excision of both primary and nodal disease with curative intent; this
             includes tonsillectomy, local excision of primary site, and nodal excision that
             removes all clinically and radiographically evident disease. In other words, to
             participate in this protocol, the patient must have clinically or radiographically
             evident gross disease for which disease response can be assessed.

          -  Carcinoma of the neck of unknown primary site origin (even if p16 positive);

          -  Prior invasive malignancy (except non-melanomatous skin cancer) unless disease free
             for a minimum of 3 years

          -  Any prior therapy for the study cancer; note that prior chemotherapy for a different
             cancer is allowable if > 3 years prior to study;

          -  Prior radiotherapy to the region of the study cancer that would result in overlap of
             radiation therapy fields;

          -  Severe, active co-morbidity;

          -  Pregnancy or women of childbearing potential and men who are sexually active and not
             willing/able to use medically acceptable forms of contraception;

          -  Poorly controlled diabetes