Measurement Tools for Radiation‐Induced Fibrosis in Head and Neck Cancer: A Systematic Review

BACKGROUND: Radiation-induced fibrosis is a common, often debilitating late effect of head and neck cancer (HNC) treatment. An updated systematic review is needed to evaluate the reliability, validity, and clinical utility of fibrosis measurement tools. METHODS: Cochrane Library, Medline, Embase.com, and Web of Science were systematically searched. Articles were independently screened by two reviewers using COSMIN checklists for risk of bias assessment, following PRISMA guidelines. RESULTS: Of 4678 articles, 17 studies describing 13 tools met inclusion: six studies assessed four patient-reported outcome measures, two assessed two clinician-reported tools, and nine assessed seven imaging modalities. The Neck Fibrosis Scale, HN-LEF Symptom Inventory, and LENT-SOMA demonstrated validity and reliability. Young's modulus was the only imaging tool demonstrating both. Imaging studies had a higher risk of bias. CONCLUSION: Several subjective tools are reliable and valid for radiation-induced fibrosis assessment in HNC. Young's modulus is the only objective imaging-based tool that provides evidence of both validity and reliability, though methodological limitations remain.