Thyroid carcinoma and hyperparathyroidism after radiation therapy for adolescent acne vulgaris.

Thyroid and parathyroid disease after head and neck irradiation in infancy and childhood is well known. Patients irradiated for facial acne were older and received a comparatively lower dose of radiation. These mitigating factors suggest a decreased incidence of thyroid and parathyroid disease in these patients. Over the past 28 years (1961 through 1989), 347 consecutive patients were operated on for radiation-associated thyroid and/or parathyroid disease. One hundred and ten patients in this group were irradiated for treatment for adolescent facial acne vulgaris. The interval between radiation exposure and thyroidectomy ranged from 7 to 57 years (mean, 30 years). The overall incidence of thyroid carcinoma was 31% (34 of 110 patients). Regional metastases in 10 patients (29%) were treated with modified radical neck dissection. Hyperparathyroidism, detected in 31% (34 of 110 patients) of this population, was treated with sub-total parathyroidectomy in all cases. The association of thyroid carcinoma and hyperparathyroidism after adolescent radiation exposure for acne vulgaris appears to be more than coincidental. The incidence of thyroid and parathyroid disease may be independent of the timing and dosage of radiation treatment. These thyroid and parathyroid tumors may develop decades after the initial radiation exposure.