A systematic review and meta-analysis of radiation-induced oral complications in head and neck cancer: Prevalence and clinical outcomes.
BACKGROUND: Radiation-induced oral complications, notably xerostomia and oral mucositis (OM), are common and debilitating in patients with head and neck cancer (HNC), adversely affecting swallowing, nutritional intake, and overall quality of life (QoL). OBJECTIVES: This review aimed to quantify the prevalence of radiation-induced xerostomia and OM and synthesize their impact on dysphagia and nutritional status among HNC patients undergoing radiotherapy (RT). METHODS: A systematic review and meta-analysis were conducted following PRISMA guidelines. Comprehensive searches were performed in MEDLINE, Scopus, SciFinder, Embase, and PubMed for studies published between January 2019 and December 2025. Data from 51 studies were extracted and synthesized. RESULTS: The pooled prevalence was 85% (95% CI: 81.6-87.9%) for xerostomia and 88.3% (95% CI: 73.9-95.3%) for any-grade OM. Severe OM (Grade 3-4) had a prevalence of 39.5% (95% CI: 23.1-58.8%). These complications were strongly interrelated and significantly associated with dysphagia (69.8%; 95% CI: 53.1-83.7%), malnutrition (66.6%; 95% CI: 37.3-95.9%), and poor QoL (pooled mean QoL score: 64.13/100). Studies employing advanced radiation techniques (e.g., IMRT) demonstrated a lower prevalence of xerostomia (OR = 0.58, 95% CI: 0.42-0.80) compared to conventional RT. CONCLUSION: Radiation-induced oral complications (xerostomia & OM) remain prevalent and clinically significant burden in HNC patients, contributing to a cascade of functional impairments and diminished QoL. These findings highlight the need for preventive strategies, symptom management interventions, and the broader adoption of advanced RT techniques. Longitudinal research is warranted to further evaluate long-term outcomes and guide patient-centered care models.