Prospective Longitudinal Swallowing Outcomes After Chemotherapy And Split-Field Imrt For Advanced-Stage T1-2 Oropharyngeal Cancer

Patients with advanced-stage (III-IV) oropharyngeal squamous cell cancers (OPSCC) with small primary tumors (T1-2) are now widely considered candidates for either primary robotic surgery or definitive radiation therapy (RT)-based approaches. The objective of this paper is to provide benchmark data on functional outcomes for patients with T1-T2, N1-2b disease treated with definitive intensity modulated RT (IMRT) who would be considered surgical candidates in current trials (i.e., ECOG-3311). A pooled dataset was analyzed from 2 institutional clinical trials of advanced-stage OPSCC treated with definitive IMRT and chemotherapy. Patients with T1-2, N1-2b classification were included. Prospective videofluoroscopy and functional questionnaires were taken before and 6, 12, and 24 months after treatment. Functional swallowing was defined as eating solid food (PSSHN≥50) without feeding tube supplementation, uncompensated aspiration, lower cranial neuropathy, or stricture. Twenty-five patients were included (median follow-up: 5 years). Tumor subsite was tonsil in 9 (36%) and base of tongue in 16 (64%). Staging distribution was T1 (8), T2 (17), and N1 (1), N2a (5), N2b (19). All patients received chemotherapy: 11 (44%) neoadjuvant/adjuvant, 12 (48%) concurrent, and 2 (8%) had both. All patients received split-field IMRT (median dose: 70 Gy; range: 66-72 Gy) with bilateral neck fields. No patient required tracheostomy or prophylactic gastrostomy. Temporary gastrostomy tubes were needed in 19 (76%) patients during treatment (median duration: 3.7 months). Three (12%) patients developed trace, compensated aspiration at 6 months; 1 recovered and 2 remained stable to 24 months without pneumonia. Overall, 24 (96%) subjects achieved functional swallowing by 1 year. MDADI scores before and 6, 12, and 24 months after chemoradiation were 93±13, 71±15, 80±19, 86±15, respectively, representing an 18% decline in perceived swallowing at 6 months (-17 points, preceding to 6 months, P<.001) that partially recovers by 2 years (+11 points, 6 to 24 months, P<.0001). One (4%) patient developed delayed hypoglossal neuropathy with refractory aspiration and pneumonia at 5 years. Despite high rates of unplanned temporary gastrostomy tube use and a clinically meaningful early drop in perceived swallowing function at 6 months, nearly all patients achieved functional recovery of swallowing by 1 year. While rare, the potential for late onset cranial neuropathies precipitating swallowing deterioration highlights the importance of long-term surveillance. These data provide a benchmark for comparison with emerging treatment approaches such as transoral robotic surgery and/or proton therapy.