Human Papillomavirus Oropharynx Carcinoma: Aggressive De-Escalation Of Adjuvant Therapy

Background: Aggressive dose de-escalated adjuvant radiation therapy (RT) in patients with human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC).Methods: Patients with HPV(+)OPSCC on a phase II clinical trial of primary surgery and neck dissection followed by dose de-escalated RT (N = 79) were compared with a cohort of patients who received standard adjuvant therapy (N = 115). Local recurrence-free, regional recurrence-free, distant metastases-free survival, and progression-free survival (PFS) were assessed.Results: Of 194 patients, 23 experienced progression at a median of 1.1 years following surgery (interquartile range [IQR] 0.7-2.0; range 0.3-5.4); 10 patients in the de-escalated cohort and 13 patients in the standard cohort. The 3-year PFS rate for the de-escalated cohort was 87%, and in the standard cohort was 90% (hazard ratio [HR] 1.18, 95% confidence interval (CI) [0.50-2.75]).Conclusion: Patients with HPV(+)OPSCC who undergo surgical resection and neck dissection and meet criteria for adjuvant therapy can undergo aggressive dose de-escalation of RT without increasing risk of progression locally, regionally or at distant sites.