Advancing Education, Research, and Quality of Care for the Head and Neck oncology patient.
Rationale: The ECOG-ACRIN E3311 Phase II trial demonstrated a 95% 2-year progression-free survival rate in 495 patients with resectable HPV-associated oropharyngeal cancer (OPC) who underwent transoral surgery (TOS) followed by de-escalated risk-based post-operative management. Previously, we reported low aspiration rates, significantly better at six months in intermediate-risk patients randomized to 50Gy vs. 60Gy post-operative RT. However, swallow efficiency remains unexplored.
Objective: Here, we report over time and across arms rates of: (i) high-grade pharyngeal residue based on modified barium swallow (MBS) studies, ii) differences in swallow safety and efficiency scores, and iii) a novel “dysphagia summary score” from site clinicians MBS assessments.
Methods: 885 MBS were performed on 314 patients from 56/59 sites at baseline, post-TOS, 6- and 24-months post-RT. Pharyngeal residue (<50% vs ≥50% residue) was recorded by site clinicians for the worst bolus performance in each MBS. DIGEST overall (D), safety (S) and efficiency (E) grades were recorded for a laboratory-graded subset of 414 studies. Site-reported residue rates were compared between arms and across time using Fisher's and McNemar tests. Wilcoxon test compared DIGEST S vs. E rates at each time point. Agreement between site-reported and laboratory-reported high-grade residue (i.e., ≥50% residue vs DIGEST E>2), and high-grade dysphagia (i.e., novel dysphagia summary=2 vs DIGEST D≥2) was assessed using Prevalence Adjusted and Biased Adjusted Kappa (PABAK).
Results: Pooling all arms, high-grade residue was reported in 2% of MBS at baseline, increasing to 15.1% after TOS (p <0.01), and decreasing to 9.3% and 6.2% at 6- and 24-months, respectively. Post-TOS residue rates did not significantly differ between arms (p=0.64). At 6-months, residue rates favored the 50Gy versus 60Gy dose arms (5.1% and 12%), although the difference was not significant (p=0.31). In the 414 lab-rated MBS, DIGEST E scores consistently showed worse outcomes than DIGEST S (p<0.01) at all time points. The novel dysphagia summary score from site-reported MBS results revealed high-grade MBS-detected dysphagia post-TOS in 21% of the entire sample that persisted at 6-months (19%) and improved modestly by 24-months (14%). Kappa agreement between site- and lab-derived results (per DIGEST criteria) was substantial for both high-grade residue (0.83, 95% CI: 0.81-0.86) and dysphagia (0.75; 95% CI: 0.72-0.78).
Conclusions: Like previously reported aspiration results, pharyngeal residue rates significantly increased after TOS but improved despite adjuvant therapy by 6 and 24 months. Residue was consistently more prevalent than aspiration, indicating that inefficiency is a primary concern for swallowing impairment in this population. The novel dysphagia summary score, easily derived from site clinicians’ MBS interpretations, exhibited strong agreement with the validated DIGEST scale, showing potential as an accessible metric in cooperative group settings.