Pattern of dysphagia after swallowing-sparing intensity-modulated radiotherapy (IMRT) of head and neck cancers: results of a mono-institutional prospective study

Background and purpose: A prospective instrumental assessment of late dysphagia using swallowing organs at risk (SWOARs)-sparing IMRT for nasopharyngeal and oropharyngeal cancers. Materials and methods: Objective instrumental assessment included fiberoptic endoscopic evaluation of swallowing (FEES) and videofluoroscopy (VFS) at baseline, and at 6 and 12 months after treatment. FEES assessed the pharyngeal residue according to the Farneti pooling score (P-score) as follows: 4–5 no dysphagia; 6–7 mild dysphagia; 8–9 moderate dysphagia; 10–11 severe dysphagia. Three different consistencies were tested for the P‑score: liquid (L), semisolid (SS), and solid (S). VFS assessed penetration-aspiration according to the Penetration-Aspiration Scale (PAS) and two different consistencies of the bolus were tested: thin liquid barium (L) and paste barium (S). Results: 38 patients were evaluable. There was a significant worsening of the P‑score at 6 months both for SS (p = 0.015) and S (p < 0.001), which persisted only for S at 12 months (p < 0.0001). Similarly, there was a significant worsening of the PAS score at 6 and 12 months (p = 0.065 and 0.039, respectively) for the S bolus. Overall, 3–7 and 10–14% aspiration after L and S was observed, respectively. Conclusions: Promising results using a SWOARs-sparing IMRT technique are reported. Therefore, treatment plans should be optimized for reducing doses to these structures.