Siobhan T. Pittock, M.B., B.Ch., Pediatric Endocrinology, Mayo Clinic: Hello, I'm Siobhan Pittock, pediatric endocrinologist at Mayo Clinic Children's Center, and today I'd like to talk about thyroid cancer in children. Cancer is a scary word. It's a scary word for everybody but thyroid cancer doesn't need to be as scary as other cancers if treated appropriately. Thyroid cancer is typically looked after by endocrinologists and surgeons rather than by the usual cancer doctors and the treatment for thyroid cancer is really quite different from other treatments of cancers.

How do you know or how would you suspect thyroid cancer? The thyroid gland sits here in the neck. It's a gland that produces thyroid hormone and the majority of thyroid cancers present with a lump either within the thyroid gland itself or in one of the lymph nodes in the neck. So it's essentially a lump in the neck is how most thyroid cancers present. Lumps in the neck are common in children. They occur because of ear infections or sore throats and many, many, many lumps in the neck are entirely normal and they're not in the least concerning. However, if lumps in the neck are very persistent, if they're large, if they are associated with a change in the voice, if they go on for a very long time, they really should be evaluated by your primary care provider who can then decide if your child's lump in the neck is something that's more worrisome than the usual type of lymphadenopathy.

If we are concerned about thyroid cancer, the best test to start figuring out if this is something we should be concerned about is an ultrasound of the neck. It should be done by someone who has a lot of experience. Cancers in the neck look different from regular lymph nodes. Lumps within the thyroid gland themselves, we call those nodules, are very, very common in adults. Many, many adults have what we call benign or harmless nodules in the thyroid gland by the time they are 50 or 60 years of age. Nodules in children are not quite so common so when we see a nodule in the thyroid gland, we have a low threshold for testing that further. The next step, if we see a nodule in the thyroid gland or if we see a lymph node on ultrasound that looks suspicious, is to do what we call a fine needle biopsy, which basically consists of a needle--just the size of a needle that we would take blood from, that size needle--passed into the area, the concerning area either in the thyroid gland or in the lymph node, and drawing out some cells, putting them on a slide and seeing if there is anything concerning looking about them. Teenagers often do this without any anesthetic. Younger children sometimes need a little bit of anesthetic.

If thyroid cancer is diagnosed, the treatment is essentially surgical to remove the thyroid gland. It's very important to work with a surgeon who is very competent in removing thyroid glands. There are a lot of very important structures in the neck which can be damaged if an inexperienced surgeon takes out the thyroid gland, and then sometimes after the surgery, some additional therapy is needed like radioactive iodine. Therapy is not necessary for every patient but it's necessary for some patients who have more extensive disease and the mainstay then of treatment is thyroid hormone replacement, so the same thyroid hormone replacement that an adult or a child who has an underactive thyroid has. It's not chemotherapy. It's just a hormone. We place patients on that for life and then follow-up is accomplished by checking blood tests, by your endocrinologist having regular physical exams--feeling the neck, and also regular ultrasound exams of the neck. There are some newer modalities of treatment that we rarely have to resort to, things like ethanol ablation, and those are also available at specialized centers.

The thyroid cancer is a cancer. It does not need to be as scary as other types of cancers but it is important that if thyroid cancer is diagnosed or if there is concern for thyroid cancer, that appropriate testing happens so the treatment can occur as early in the course as possible.

Jan. 17, 2023