Objectives We have observed that patients with dysphagia after radiotherapy (RT) for nasopharyngeal carcinoma (NPC) have substantially worse swallowing function than patients treated with RT of other sub-sites. The purpose of this investigation was to describe swallowing dysfunction after RT for NPC and compare swallowing parameters to patients receiving RT for cancer from another site. Methods Fluoroscopic swallowing data of persons with dysphagia after RT for NPC was abstracted from a clinical database. Objective swallowing parameters were compared to age- and gender-matched normal controls and to cancer stage-matched patients treated with RT for oropharyngeal cancer (OPC). Results 13 patients with NPC were compared to 13 controls and 13 patients with OPC. The average duration from RT to fluoroscopic study was 74 months for NPC and 24 months for OPC (p=.06). 62% of NPC and 47% of OPC were gastrostomy tube-dependent. 92% of NPC patients aspirated or penetrated compared to 62% of OPC patients. The maximal average tolerated bolus was 10.6cc for NPC and 22.2cc for OPC (p<.02). Mean hyolaryngeal elevation was 4.02 (±1.27) for normals, 2.96 (±0.86) for OPC, and 2.45 (± 1.17) for NPC (p<.01). Opening of the pharyngoesophageal segment was lower than normal in both NPC and OPC. Pharyngeal constriction was 0.08 (±0.09) for normals, 0.40 (±0.24) for OPC and 0.45 (±0.27) for NPC (p<.001). Conclusions The data suggest that patients with dysphagia after radiotherapy for NPC present at a later date, have significantly less hyolaryngeal elevation, have weaker pharyngeal constriction, and cannot tolerate as large a bolus as patients treated with radiotherapy for OPC.
