Complications associated with therapeutic neck radiation

Purpose: This retrospective study of patients who underwent neck radiation as part of their treatment for squamous cell carcinoma of the oral cavity sought to identify and quantify the morbidity associated with this treatment. Patients and Methods: Thirty-five patients who received neck radiation between 1985 and 1992 were randomly recalled for examination. All patients had been treated in a standardized fashion by the Department of Radiation Oncology. The long-term effects of neck radiation on skin changes, thyroid function, and neck range of motion, of atherosclerotic carotid artery disease, xerostomia, and glottic structures were measured. Results: Fifty-seven percent of patients demonstrated grade 1 skin changes. No severe changes were noted, and no development of secondary neoplasia was observed. There was no linear trend observed between radiation dose and skin changes. Hypothyroidism developed in 14.3% of patients within 3.5 years posttreatment. Logistic regression demonstrated a significant association between hypothyroidism and radiation dose. Limitation of neck mobility was the most significant complication with deficits demonstrated in all ranges of motion. Carotid bruits were documented in 14.3% of patients, with a significant association between the higher neck dosage in N+ cases. Xerostomia was found in 68% of patients. There was persistent glottic erythema in 11.4% of patients. Conclusions: The results of this study indicate that there are persistent complications after neck radiation, which include limitation of neck movement, diminished thyroid function, accelerated carotid artery narrowing, and skin and salivary changes.