External irradiation for malignant thyroid tumors.

Thirty-eight patients with residual or recurrent primary thyroid cancers which did not take up 1-131 were treated with external beam irradiation. Excluding 5 patients with malignant lymphoma, there were 23 patients with local disease and 10 with distant metastases. Doses ranged from 3,500 to 7,000 rads (35-70 Gy) among the 23 with local disease; local tumor control was achieved in 8. Six are alive and well 2-11 years later. External beam irradiation should be considered in locally advanced, incompletely resected, recurrent and metastatic thyroid malignancies of all histological types without 1-131 uptake. Reviewed are the age and sex distribution, histology, stage, extent of surgery, and dose and radiotherapy technique as they affect survival and patterns of failure.