Two months after finishing 60Co external irradiation to treat squamous cell carcinoma of the larynx, a 47-year-old man became hyperthyrold. Although the thyroid gland was not tender, the radioactive iodine uptake was diminished. After subsequent periods of euthyroidism and hypothyroidism, the patient's thyroid function spontaneously returned to normal. The features of this case mimic the syndrome of painless granulomatous thyroiditis. Although hypothyroidism is frequently observed following radiation thyroiditis, hyperthyroidism from external radiation has not been reported. Despite this low frequency, diagnosis is important to permit prompt, symptomatic treatment of the thyrotoxic phase.
Fachnie, J. David and Rao, Sudhaker D.
"Painless Thyroiditis with Hyperthyroidism Following External Irradiation to the Neck,"
Henry Ford Hospital Medical Journal
: Vol. 28
Available at: https://scholarlycommons.henryford.com/hfhmedjournal/vol28/iss2/13