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

• Disease-free survival (DFS) [ Time Frame: 2 years ] [ Designated as safety issue: No ]
  Survival probability will be estimated by Kaplan-Meier analysis and survival curves for patients with adjuvant radiotherapy w and w/o chemotherapy will be compared by use of log-rank statistic.
• Locoregional control [ Time Frame: 2 years ] [ Designated as safety issue: No ]
  Rate of patients with no recurrence at original oropharyngeal site or in the neck nodal basins.

• Distant metastasis rates [ Time Frame: Up to 5 years ] [ Designated as safety issue: No ]
  Assessed by biopsy or imaging-detected recurrent disease at sites away from the original primary and cervical zone.
• Disease specific survival [ Time Frame: Up to 5 years ] [ Designated as safety issue: No ]
  Defined as time from surgery to death from recurrent oropharyngeal cancer or treatment-related death.
• Cumulative incidence of complications/acute toxicity [ Time Frame: 4.5 months ] [ Designated as safety issue: Yes ]
  Assessed by the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0.
• Function and quality of life (QOL) [ Time Frame: Up to 24 months ] [ Designated as safety issue: No ]
  Multiplicity corrected tests for trend (i.e., non-parametric Jonckehere-Terpstra test) used to compare patients with adjuvant radiotherapy w/ and w/o chemotherapy at single time points (study entry 1, 3, 6, 12 and 24 months).

This randomized 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. After the surgery, patients are randomized to receive either radiation alone, or radiation and weekly cis-platinum during therapy. Patients are then followed for cancer, functional and quality of life outcomes.

• Radiation: Intensity-modulated radiation therapy (IMRT)
  Patients undergo postoperative IMRT once daily, 5 days a week, for 6 weeks.
• Drug: Cisplatin
  Cisplatin IV on days 1, 8, 15, 22, 29, and 36 of radiation therapy.

• Experimental: Radiotherapy
  Patients undergo postoperative IMRT once daily, 5 days a week, for 6 weeks.
  Intervention: Radiation: Intensity-modulated radiation therapy (IMRT)
• Active Comparator: Radiotherapy, cisplatin
  Patients undergo postoperative IMRT as in Arm I. Patients also receive cisplatin IV on days 1, 8, 15, 22, 29, and 36 of radiation therapy.
  Interventions:

  • Radiation: Intensity-modulated radiation therapy (IMRT)
  • Drug: Cisplatin

Inclusion Criteria:

• Patient must have histologically confirmed p16 positive squamous cell carcinoma of the oropharynx (OPSCC).
• Patient must have undergone transoral resection of their T1-4a oropharynx primary to a negative margin, and a neck dissection(s).
• Patient's disease must be pathological N-stage positive.
• Patient's disease must show extracapsular spread (ECS) in their nodal metastasis verified by central pathologist's review.
• Patients with synchronous primaries are included.
• Patients with unknown primaries are included if the diagnosis of a primary site in the oropharynx is made during the surgery.
• Patients with recent excisional node biopsies/neck dissections are included if material is evaluable for extracapsular spread.
• Patient must be ≥ 21 years of age.
• ECOG performance status ≤ 2 (Karnofsky ≥60%; see Appendix A).
• Patients must have normal organ and marrow function as defined below:
• leukocytes ≥3,000/mcL
• absolute neutrophil count ≥1,500/mcL
• platelets ≥100,000/mcL
• total bilirubin <1.5 X upper normal institutional limit
• AST(SGOT)/ALT(SGPT) ≤2.5 X institutional upper limit of normal
• creatinine within normal institutional limits OR
• creatinine clearance ≥60 mL/min/1.73 m2 for patients with creatinine levels above institutional normal
• Patient (or legally authorized representative) must be able to understand and willing to sign a written informed consent document.

Exclusion Criteria:

• Patient must not have pathologically N stage negative disease.
• Patient must not have outside nodal tissue from previous neck biopsy/neck dissections in which ECS cannot be confirmed or denied.
• Patient must not have a true unknown primary in which permanent section results are negative for malignancy in completely excised ipsilateral oropharyngeal tissue (palatine and lingual tonsil).
• Patient must not have distant metastatic disease at presentation.
• Patient must not have gross residual and/or microscopic disease present after surgery including re-resection(s), per the operative and pathology report.
• Patient must not have a history of prior invasive malignancy (except non-melanomatous skin cancer) unless disease free for a minimum of 3 years; noninvasive cancers (for example, carcinoma in situ of the oral cavity, larynx, breast or cervix are all permissible) are permitted even if diagnosed and treated < 3 years ago.
• Patient must not have had previous systemic chemotherapy for the study cancer. (Note: prior chemotherapy for a different cancer is allowable).
• Patient must not be receiving any other investigational agents.
• Patient must not have had any prior radiotherapy to the region of the study cancer that would result in overlap of radiation therapy fields
• Patient must not have any life-threatening comorbid illnesses e.g. stroke with major sequelae or myocardial infarction/ unstable angina within the preceding 3 months or psychiatric illness/social situations that would limit compliance with study requirements.
• Patient must not be pregnant or breastfeeding. If a woman of childbearing potential, patient must agree to use medically acceptable forms of contraception.

Both men and women and members of all races and ethnic groups are eligible for this trial.