Precision rehabilitation for swallowing dysfunction after radiotherapy in head and neck cancer: current evidence, key controversies, and future perspectives.

Background: Swallowing dysfunction (dysphagia) is a devastating and highly prevalent sequela following radiotherapy (RT) for head and neck cancer (HNC), severely impairing patients' quality of life and nutritional status. While rehabilitation is the cornerstone of management, the translation of evidence into effective clinical practice is hampered by significant heterogeneity in interventions, conflicting outcomes, and poor adherence. Methods: This narrative review critically synthesizes current evidence from systematic reviews, randomized controlled trials, and prospective cohort studies published between January 2015 and March 2025. A structured literature search was conducted in the PubMed, Web of science and Embase databases using combinations of keywords including "head and neck neoplasms," "dysphagia," "radiotherapy," "rehabilitation," "swallowing exercises," "adherence," "frailty," and "precision medicine." The selection focused on high-impact studies that addressed key challenges, controversies, and emerging paradigms in the field. It moves beyond a descriptive summary to evaluate the contradictions in the literature and propose a framework for precision rehabilitation. Results: The efficacy of swallowing exercises is well-documented, but critical controversies persist. These include the optimal timing (prophylactic vs. reactive), the superiority of specific exercise regimens, and the unpredictable impact of radiotherapy dose constraints on functional outcomes beyond traditional pharyngeal constrictors. A pivotal, yet often overlooked, factor is patient adherence, which is multifactorial and can be improved through behavioral change techniques and technology-assisted strategies (e.g., mHealth, wearable sensors). Furthermore, emerging evidence highlights the need to consider specific patient phenotypes, such as pre-treatment frailty and the presence of internal lymphedema, which significantly influence rehabilitation success. The integration of objective assessments (e.g., HRM, DIGEST) is crucial for quantifying dysfunction and tailoring interventions. Conclusion: The field of dysphagia rehabilitation in HNC is evolving from a one-size- fits-all approach towards precision medicine. Future efforts must focus on developing personalized rehabilitation pathways based on individual risk stratification (e.g., frailty, dose to specific musculature), integrating technology for monitoring and motivation, and fostering interdisciplinary collaboration among oncologists, speech-language pathologists, and behavioral scientists to bridge the gap between research evidence and lasting functional recovery.