Previous studies of this type of head and necl cancer have shown high rates of cancer control but result in many short and long term side effects when treated with high dose radiation and chemotherapy. Recently, investigators have noticed similar high rates of cancer control in small numbers of patients who receive less intensive treatments using lower doses of radiation, smaller radiation fields with chemotherapy. It is expected that the side effects of treatment with lower doses of radiation would be less.

For this reason this study is looking at a different regimen of reducing the intensity of the treatment.

The purpose of this study is to compare any good and bad effects of using lower dose smaller fields radiation therapy and chemotherapy with published outcomes. This study will allow the researchers to know whether these different approaches are better, the same, or worse than the usual approach. To be better, the study approach should result in the same survival rate of the usual approach (about 85 out of 100 patients alive and free of cancer at 2 years) but with less long-term side effects.

There will be about 30 people taking part in this study. This study has one study group. All the people on the study will receive radiation therapy once a day, 5 days a week (for a total of 55 Gy over 5 weeks) and chemotherapy, cisplatin, (given through the vein for about 30-60 minutes) once a week for 5 weeks.

Medications and saline solutions to prevent side effects of chemotherapy may also be given by vein and may prolong your time in the chemotherapy clinic to as much as 4-6 hours.

Standard regimen not delivered on this study pertains to radiation therapy and chemotherapy, cisplatin in a schedule of 5 treatments a week for a total of 69.96 Gy over 6.5 weeks.

Inclusion Criteria:

• Pathologically proven diagnosis of squamous cell carcinoma of the oropharynx (tonsil, base of tongue, soft palate, or oropharyngeal walls)
• Patients must have clinically or radiographically evident measurable disease at the primary site or at nodal stations.
• P16-positive based on local site immunohistochemical tissue staining
• Clinical stage T1-3, N1-2, M0 (AJCC, 8th ed.)
• Age ≥ 65.
• Normal organ and marrow function within 14 days prior to registration defined as follows:
• Absolute neutrophil count ≥ 1,500/mcL
• Platelets ≥ 100,000/mcL
• Hemoglobin ≥ 8.0 g/dL
• Total bilirubin ≤ 1.5× institutional upper limit of normal (ULN)
• AST(SGOT) or ALT(SGPT) ≤ 3.0 × institutional ULN
• Serum creatinine ≤ 1.5× ULN

Exclusion Criteria:

• Metastatic disease
• Recurrent disease after primary management Cancers with center of mass is outside the oropharyngeal boundaries
• Synchronous double primaries
• Prior radiotherapy for lymphoma or other malignancy
• Prior systemic therapy including immunotherapy
• Severe active comorbidity where life expectancy is <1 year.
• Autoimmune disease
• Uncontrolled HIV