Dysphagia optimized radiotherapy to reduce swallowing dysfunction severity in patients undergoing treatment for head and neck cancer: A systematized scoping review.

This study involved a systematized scoping review to coalesce current evidence on dysphagia outcomes achieved through active sparing of the swallowing structures in patients receiving radiotherapy for head and neck cancer. Eligible publications between 2007 and 2017 were reviewed and synthesized regarding participant demographics, treatment regimens, swallowing structures chosen for optimization, dosimetric constraints, and dysphagia measures. Nine prospective cohort studies were included. Key structures routinely spared included pharyngeal constrictor muscles (PCMs), glottic larynx (GL), supraglottic larynx (SGL), and esophageal inlet muscle. Shorter enteral feeding times and reductions in Common Terminology Criteria for Adverse Event (CTCAE) grade 3 dysphagia toxicity were observed when dose to the larynx (GL and SGL) and PCMs was constrained to < 50 and < 60 Gy, respectively. Emerging evidence supports "active" sparing of the swallowing structures at the time of radiotherapy planning to reduce dysphagia severity, with no compromise to planning target volumes and locoregional control rates.