Functional impact of transoral surgery and risk-based adjuvant therapy in human papillomavirus-associated oropharyngeal cancer: swallowing outcomes from ECOG-ACRIN E3311.

Purpose: The ECOG-ACRIN E3311 Phase II trial demonstrated outstanding disease control (90.6% 54-month PFS) following transoral surgery (TOS) with de-escalated, risk-based postoperative management in resectable HPV-associated oropharyngeal cancer (OPC). The goal of de-escalation was functional preservation. The objective of this work was to evaluate clinician-graded modified barium swallow (MBS) studies from E3311 over time and across arms for: (i) aspiration and high-grade pharyngeal residue rates, (ii) differences in swallow safety and efficiency, and (iii) accuracy of site clinician reporting against central MBS review. Patients and methods: 885 MBS studies were performed on 314 patients from 50/59 sites at baseline, post-TOS, and 6- and 24-months post-RT. Swallow outcomes (aspiration, high-grade residue) were recorded by site clinicians. A subset of 414 MBS studies was centrally graded using penetration-aspiration scale (PAS) scores and Dynamic Imaging Grade of Swallowing Toxicit Results: Aspiration, residue and dysphagia rates significantly increased from baseline to post-TOS (p<0.01) and then decreased modestly at 6- and 24-months. At 6 months, swallow outcomes favored the 50Gy vs. 60Gy arm, with significantly lower aspiration and high-grade dysphagia rates but this difference was not maintained at 24-months. MBS results reported by site clinicians demonstrated substantial agreement with the central laboratory (PABAK: 0.75-0.84, p<0.01). Conclusions: Swallowing worsened after TOS but improved by 6 and 24 months despite adjuvant therapy. De-escalated adjuvant RT at 50 Gy reduced acute aspiration. Site-reported MBS metrics strongly aligned with DIGEST, showing potential as an accessible metric in cooperative group settings.