Trial of De-Intensified Post-operative Chemoradiation Following Robotic Surgery for HPV-positive Oropharyngeal Cancer

Inclusion Criteria

• •1. AJCC 8th edition T0-3N0-2 p16-positive oropharyngeal (tonsil, base of tongue, glossotonsillar sulcus, soft palate, oropharyngeal wall) squamous cell carcinoma or squamous cell carcinoma of unknown primary involving the cervical lymph nodes. Cytologic diagnosis from a cervical lymph node is sufficient for diagnosis in the presence of clinical evidence of a primary tumor in the oropharynx.
• •2. For patients with pT0 tumors (unknown primary), there must be at least one metastatic lymph node present in cervical level II.
• •3. p16 should be strongly and diffusely positive in the nuclear and cytoplasmic component in greater than 70% of the tumor cells.
• •4. Have undergone or will undergo gross total resection of all known disease in the head and neck via transoral robotic surgery. For patients with unknown primary tumors, a minimum of an ipsilateral tonsillectomy and base of tongue resection is required.
• •5. Have undergone or will undergo neck dissection.
• •6. Have at least one of the following after surgery:
• •* Pathologic stage T3
• •* 2 or more positive lymph nodes
• •* At least one lymph node \>3cm
• •* Lymphovascular invasion
• •* Perineural invasion
• •* Extranodal extension
• •* Close/positive margins: Close margins are considered \<3mm from the peripheral margins and \<1mm from the deep margin on the en bloc specimen, unless the area of close margin is re-resected and without carcinoma.
• •7. Age ≥ 18 years old
• •8. ECOG performance status 0 or 1 within 56 days of start of chemoradiation.
• •9. Women of childbearing potential require a negative serum or urine pregnancy test within 28 days prior to start of chemoradiation.
• •10. Written informed consent obtained from subject and ability for subject to comply with the requirements of the study.
• •11. Adequate hematologic and renal function within 30 days of start of chemoradiation, defined as:
• •* Hemoglobin ≥ 9.0 g/dL
• •* Platelets ≥ 100, 000 cells/mm3
• •* ANC ≥ 1.5 X 109/L
• •* Total bilirubin ≤ 1.5 x upper limit of normal (ULN)
• •* Aspartate aminotransferase/alanine aminotransferase ≤ 3.0 x upper limit of normal (ULN)
• •* Serum creatinine ≤1.5 x upper limit of normal (ULN) OR a calculated creatinine clearance ≥60 mL/min