World Journal of Otorhinolaryngology-Head and Neck Surgery (Mar 2020)
Dysphagia after chemo-radiation for nasopharyngeal cancer: A scoping review
Abstract
Objective: Nasopharyngeal cancer (NPC) has distinct characteristics regarding its global prevalence, initial presentation, management and patient outcomes compared to other subtypes of head and neck cancer (HNC). The mainstay of NPC treatment is chemo-radiation (C/RT) and while dysphagia is a known early and late toxicity of C/RT treatment, the nature of dysphagia post NPC treatment has had limited investigation. The objective of this review is to summarise the existing evidence regarding dysphagia following NPC to inform the future research agenda for this population. Dysphagia incidence, characteristic deficits observed across the phases of swallowing, efficacy of current dysphagia interventions, and effect on quality of life will be explored. Data sources: Databases including MEDLINE, CINAHL, Embase, Scopus and Web of Science were included. Methods: A scoping review was conducted according to PRISMA-ScR guidelines. Two independent reviewers screened selected full text articles. Results: Of the initial 2495 articles found, 28 articles were included. Reports of penetration and aspiration varied widely (0%–91.6%), with high rates of silent aspiration identified in 2 studies (42%, 66%). Oral, pharyngeal and upper esophageal phase impairments were reported. Of these, upper esophageal stasis and multiple pharyngeal stage deficits were most prevalent. The pharyngeal constrictors were found to have a significant dose–effect relationship and shielding to the anterior neck field was effective to preserve swallowing function. Six treatment studies were identified with limited evidence supporting the use of neuromuscular electrical stimulation, dilatation and swallowing exercises. Quality of life was adversely affected. Conclusions: Dysphagia is a prevalent early and late problem post NPC treatment, with impairments across all phases of the swallow. Studies on preventing dysphagia and treatment efficacy remain limited. More systematic study of the nature of dysphagia and the efficacy of treatment in this population is warranted.