Vocal cord palsy: possible late complication of radiotherapy for head and neck cancer.

Cranial nerve palsies are uncommon complications of radiotherapy for head and neck cancer. A review of the literature reveals that cranial nerve damage after radiotherapy has been reported for the optic, oculomotor, trigeminal, abducens, cochlear, vagus, spinal accessory, and hypoglossal nerves. The hypoglossal nerve appears to be the most commonly affected, and the recurrent laryngeal nerve is seldom involved. The case histories of three patients who developed vocal cord palsy from 21 to 34 years after a course of curative or postoperative radiotherapy for carcinoma of the head and neck are presented. Two patients had bilateral palsy, and in the third patient, bilateral damage cannot be excluded. Physical examination and radiographic investigations on admission and on follow-up did not demonstrate any evidence of tumor recurrence, cervical or distant metastases, or second primary tumors. The distinction between irradiation-induced palsy and that due to malignancies is emphasized.