<b>General</b>

Radiation treatment plays an important role in the management of head and neck cancer.

Cranial irradiation for nasopharyngeal cancers carries a risk of other structures becoming injured by the radiation. Incidental damage to the hypothalamus of the brain can cause hypopituitarism [See Brain.]

Unfortunately several radiation-induced side effects may occur including mucositis, hyposalivation, radiation caries, trismus ['locked' jaw] and radiation bone injury possibly progressing to tooth loss or osteoradionecrosis. It is generally accepted that most side effects can be prevented or reduced in severity. There should be a general protocol for prevention and treatment of oral side effects, and timely referral to a dental team before irradiation starts.

Eustachian tube patency showed deterioration if maximum irradiation dosage for nasopharyngeal cancers was more than 70 Gy. Mucosal reactions were observed in 30-35% of the patients with tumors of the oral mucosa. The most frequent radiation damage in a long-term period was fibrotic changes of the skin and subcutaneous connective tissue.

A study was done on patients with nasopharyngeal carcinoma, to compare accelerated-hyperfractionated radiotherapy with conventional dosing.  In this study, the survival criteria were not significantly different.  However there was significantly increased radiation-induced damage to the CNS.There was more damage to the temporal lobe, cranial nerves, optic nerve, neck soft tissue, and the pituitary gland. And the complications occurred sooner.