Radiation-Induced Fibrosis in Head and Neck Cancer: Challenges and Future Therapeutic Strategies for Vocal Fold Treatments.

Head and neck cancer encompasses a diverse group of malignant neoplasms originating in regions such as the oral cavity, oropharynx, hypopharynx, larynx, sinonasal cavities, and salivary glands. HNC represents a significant public health challenge, and recent reports indicate an increment in the incidence of HNC in young adults. In 2020, approximately 377,700 new HNC cases and 177,800 HNC-related deaths were reported globally. Major risk factors include tobacco smoking, alcohol consumption, and human papillomavirus (HPV) infections. HNC impacts vital functions such as breathing, swallowing, and speech. Treatments for this type of cancer within this complex anatomy include surgery, radiotherapy, and chemotherapy combinations. Radiotherapy is often an essential component of both curative and palliative HNC treatment, balancing tumor control with the preservation of function and appearance. However, its use can damage adjacent normal tissues, causing acute or chronic toxicity. One complication of HNC irradiation is VF fibrosis, which leads to severe voice impairments, significantly affecting patients' quality of life. Fibrosis involves excessive and aberrant deposition of extracellular matrix, driven by factors such as TGF-β1 and inflammatory cytokines, which ultimately impair the flexibility and function of VF. Current radiation-induced fibrosis treatments primarily focus on symptom management and include systemic therapies like corticosteroids, anti-inflammatory drugs, and antioxidants. However, these treatments have limited efficacy. Experimental approaches targeting molecular pathways involved in fibrosis are being explored. Given the limitations of these treatments, advancing research is crucial to develop more effective therapeutic strategies that can significantly improve the quality of life for HNC patients, especially those vulnerable to VF fibrosis.