The Benefit of Adjuvant Radiation in Surgically‐Treated T1‐2 N1 Oropharyngeal Squamous Cell Carcinoma

IMPORTANCE: The benefit of adjuvant radiation in surgically treated T1‐2N1 oropharyngeal cancer without adverse pathologic features remains unclear OBJECTIVES: To compare population‐level survival outcomes in surgically‐treated T1‐2N1 oropharyngeal squamous cell carcinoma (OPSCC) with and without the use of adjuvant radiation. STUDY DESIGN: Retrospective population‐based study using the Surveillance, Epidemiology, and End Results (SEER) registry data from 1998–2011. SETTING: Population‐level study. PARTICIPANTS: Patients with T1‐2N1 OPSCC treated with surgical resection and neck dissection with or without adjuvant radiation. INTERVENTION(S) FOR CLINICAL TRIALS OR EXPOSURE(S) FOR OBSERVATIONAL STUDIES: The use of postoperative adjuvant radiation. MAIN OUTCOME(S) AND MEASURES: Overall and disease‐specific survival. RESULTS: Radiation was utilized in 74% of patients and was positively associated with extracapsular extension and well‐differentiated histology. The use of radiation was associated with improved mean overall survival (124 v. 108 months, p=0.023) and a non‐significant increase in mean disease‐specific survival (138 v. 131 months, p=0.053). CONCLUSIONS AND RELEVANCE: The use of adjuvant radiation is associated with improved survival in surgically‐treated T1‐2N1 squamous cell carcinoma of the oropharynx with unknown HPV status. LEVEL OF EVIDENCE: IV