Inclusion Criteria:

          1. Pathologically-proven diagnosis of T1-3 (up to 6 cm), N0-2 (AJCC 8th edition) p16
             positive squamous cell carcinoma of the oropharynx (except T1-2N0 as noted in the
             exclusion criteria)

          2. ≤10 pack-year smoking history and not actively smoking

          3. Age ≥18 years

          4. ECOG performance status 0-2

          5. Women of child-bearing potential and men must agree to use adequate contraception
             (hormonal or barrier method of birth control; abstinence) prior to study entry, for
             the duration of study participation, and for 90 days following completion of therapy.
             Should a woman become pregnant or suspect she is pregnant while participating in this
             study, she should inform her treating physician immediately.

          6. Negative serum or urine pregnancy test within 2 weeks before registration for women of
             childbearing potential.

          7. Ability to understand and the willingness to sign a written informed consent.

        Exclusion Criteria:

          1. Distant metastasis

          2. T1-2N0 (AJCC 8th edition) p16 positive squamous cell carcinoma of the oropharynx
             (candidates for definitive RT alone or surgery alone)

          3. Inability to receive concurrent weekly cisplatin due to comorbid conditions

          4. Synchronous non-skin cancer primaries outside of the oropharynx, oral cavity, larynx,
             and hypopharynx except for low- and intermediate-risk prostate cancer and
             well-differentiated thyroid cancer. For prostate cancer, patient should not be
             receiving active treatment. For thyroid cancer, thyroid surgery may occur before or
             after radiation treatment, provided all other eligibility criteria are met.

          5. Prior invasive malignancy with an expected disease-free interval of less than 3 years

          6. Prior radiotherapy to the region of the study cancer that would result in overlap of
             radiation fields

          7. Subjects may not be receiving any other investigational agents for the treatment of
             the cancer under study.

          8. History of allergic reactions attributed to compounds of similar chemical or biologic
             composition to the chemotherapy agents in this study

          9. Uncontrolled intercurrent illness including, but not limited to, ongoing or active
             infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
             arrhythmia, or psychiatric illness/social situations that, in the opinion of the
             investigator, would limit compliance with study requirements

         10. Subjects must not be pregnant or nursing due to the potential for congenital
             abnormalities and the potential of this regimen to harm nursing infants.

         11. History of severe immunosuppression, including HIV, organ or autologous or allogeneic
             stem cell transplant, or active immunosuppressive medication at the time of enrollment