Practical considerations in reducing swallowing dysfunction following concurrent chemoradiotherapy with intensity-modulated radiotherapy for head and neck cancer

Data have emerged that the addition of concurrent chemotherapy to radiation can lead to swallowing dysfunction that may have an impact on patient quality of life and lead to significant morbidities such as poor nutritional status, enteral feeding tube dependence, and aspiration pneumonia. Although intensity-modulated radiation therapy (IMRT) for head and neck cancer was initially developed to spare the parotid gland to reduce xerostomia, attention has recently focused on its utility to selectively decrease radiation dose to specified anatomic structures responsible for a functional swallow. Recent reports have proposed a variety of dose thresholds or constraints to these swallowing-related structures, which may guide IMRT planning with the aim of reducing dysphagia. This critical review of the current literature assesses the feasibility of IMRT to maintain swallowing function and appraises the various dosimetric parameters that have been proposed to help minimize long-term dysphagia.