Radiation therapy can damage salivary glands, causing salivary hypofunction and xerostomia. (Refer to the Oral Complications of Head and Neck Radiation section of this summary for more information.) In addition, selected chemotherapeutic agents (singly or in combination) have been implicated in causing salivary dysfunction and xerostomia. However, it has not been possible to draw consistent conclusions about the effects of cancerchemotherapy on salivary gland function.
Cancer prevention is action taken to lower the chance of getting cancer. In 2014, about 1.6 million people will be diagnosed with cancer in the United States. In addition to the physical problems and emotional distress caused by cancer, the high costs of care are also a burden to patients, their families, and to the public. By preventing cancer, the number of new cases of cancer is lowered. Hopefully, this will reduce the burden of cancer and lower the number of deaths caused by cancer.
Difficulties with speaking, eating and drinking, or drooling may affect mental health and put patients and family members in social isolation.
All of these problems, plus the patient perception of swallowing difficulties, significantly decrease health-related quality of life.[3,4]
Dysphagia is most prominent in patients with head and neck cancers but may also develop in patients with other malignancies as a symptom of oropharyngeal or esophageal mucositis or infection. In addition, dysphagia can be associated with graft-versus-host disease.
The prevalence and severity of pretreatment dysphagia associated with head and neck tumors depend on tumor stage and localization. Pretreatment dysphagia is most prevalent in patients with pharyngeal and laryngeal cancers. Surgical interventions for head and neck tumors result in anatomic or neurologic insults with site-specific patterns of dysphagia. In general, the larger the resection, the more swallowing function will be impaired.
The severity of radiation-induced dysphagia depends on the following:
Intensified schedules and the use of chemoradiation therapy have been shown to improve locoregional control and survival but come at the cost of more severe acute and chronic side effects. Intensity-modulated radiation therapy (IMRT) has emerged as an effective technique to deliver the full radiation dose to the tumor and regions at risk while reducing exposure of surrounding healthy tissues. However, the preservation of anatomy does not necessarily translate into the preservation of swallowing function.