Radiotherapy in the Region of the Head and Neck and the Consequential Changes in Normal Tissues / 대한연하장애학회지

ABSTRACT

Radiotherapy is a crucial non-surgical modality for head and neck cancer. With increasing radiation dose, the possibility of tumor control increases but the probability of toxicity to the surrounding normal tissue also increases. The subsequent changes in the normal tissues after radiotherapy can occur within a few minutes, or even several years. The early effects occur in rapidly proliferating tissue and tend to cause inflammation and are usually reversible. The late effects occur in more slowly proliferating tissues and the pathogenesis includes fibrosis, atrophy, and vascular damage. The early and late responses of the normal tissue can be dose-limiting factors in radiotherapy for head and neck cancer, affecting the therapeutic efficacy and quality of life of cancer survivors. Radiation-induced oral mucositis is the major limiting acute toxicity of radiotherapy for head and neck cancers and can lead to treatment interruption and suboptimal disease control. On the other hand, the most problematic late toxicities in the region of the head and neck are decreased secretion of saliva and dysfunction in swallowing. This review investigated the pathophysiology of radiation-induced toxicity: oral mucositis, xerostomia and dysphagia.