A thyroid nodule is an abnormal growth of thyroid cells in the thyroid gland. The incidence in adults is now as high as 50%. The chance of having thyroid nodules increases with age, and is more common in women than men.

The exact cause of thyroid nodules is still unclear. Besides the abnormal growth of thyroid cells, some other factors are also responsible for the formation of thyroid nodules, including deficiency of iodine, cysts in the thyroid, and chronic inflammation of the thyroid.

Due to the increased awareness of the need for annual health checks, and the enhanced accuracy of ultrasound imaging, more and more thyroid nodules are being detected. While the frequency of thyroid nodules is high, if one is discovered you should not panic as only a small percentage of thyroid nodules are cancerous.

“A primary characteristic of thyroid nodules is they grow slowly and continuously. Even with cancerous nodules, the growth process is longer compared with other malignant tumors.” said Dr. Lai Yanni, an endocrinologist consulting in Shanghai United Family Hospital.

An ultrasound check is the most convenient method to detect and monitor thyroid nodules. If detected, doctors typically require patients to undergo ultrasound checks of the thyroid gland every 6-12 months to monitor their development. If the nodules remain stable, patients just need regular ongoing checkups.

“The high-frequency ultrasound exam can provide plenty of information about the location, numbers, size, shape, and structure of thyroid nodules.” Dr. Lai said. “However, in order to confirm whether the nodule is benign or not, we need to perform a Fine Needle Aspiration Biopsy (FNAB). ”

“Aspiration means a needle is inserted into the suspicious nodules with the guidance of ultrasound to collect samples. The samples will be sent to a laboratory and analyzed through a microscope and other techniques. The whole process is short and we can apply local anesthetic on the neck to reduce any pain,” she said. “The process is not scary.”

If the pathological findings determine the nodule is cancerous, the patient will be referred to the surgical department for further evaluation and treatment. Currently, surgery is typically the best solution, experts say.

If the biopsy shows noncancerous thyroid nodule(s), overtreatment is not recommended. Patients typically just need regular follow ups. That means having a physical exam, an ultrasound exam, and thyroid function tests at regular intervals. If a benign thyroid nodule remains unchanged, patients may never need treatment, Dr. Lai said.

For a noncancerous thyroid nodule, if the blood tests indicate the thyroid gland isn’t producing enough thyroid hormones, patients may need to begin thyroid hormone therapy. In some cases a noncancerous thyroid nodule may still require surgery. These would include the presence of large nodules that interfere with breathing or swallowing, or with large multi-nodular goiters that can constrict airways, the esophagus, or blood vessels.

Experts maintain that routine medical health checks, including a blood test of the thyroid function and an ultrasound of the thyroid, are necessary to detect thyroid nodules and then determine whether medical intervention or simple ongoing monitoring is recommended.