Doctors described the case of a 68-year-old woman with a rare and aggressive form of thyroid cancer. The cancer, which started in her thyroid, had spread to her lungs and bones. These distant tumors were also producing thyroid hormones, causing her to have hyperthyroidism (an overactive thyroid).
She received two treatments with radioactive iodine (RAI) therapy. This is a standard treatment for some thyroid cancers because thyroid cells absorb iodine. After treatment, her hormone levels shifted from hyperthyroidism to hypothyroidism, which was the intended effect. A follow-up CT scan also showed a significant reduction in the size of the lung tumors.
No safety concerns or side effects from the treatment were reported in this case. The main reason for caution is that this is a report about just one patient. Hyperfunctioning metastases from this type of cancer are very rare. What worked for her might not work for others, and more research is needed.
Readers should understand this is a detailed medical report, not a new standard of care. It highlights that when thyroid cancer spreads, doctors should check if the new tumors are producing hormones. It also shows that RAI therapy can still be an option if the spread tumors absorb iodine, even in aggressive cases.