1. Can I prevent thyroid nodules by eating iodized salt?
Most thyroid nodules are caused by iodine deficiency, but a long-term high iodine diet can also stimulate thyroid tissue hyperplasia and nodules by increasing the level of thyroid stimulating hormones in the body. Because iodine is already added to salt, long-term consumption of seafood with high iodine content, such as kelp, can also easily cause thyroid nodules.
2. Why is the incidence of thyroid nodules increasing year by year?
This is related to modern lifestyle, increased nightlife, increased mental stress, excessive iodized salt intake, and also to the increasing resolution of ultrasound, as lesions of 2-3mm can be seen under ultrasound.
3. Do thyroid nodules have a high rate of malignancy? How do you determine whether they are benign or malignant?
Only 5%-15% of thyroid nodules are malignant, i.e. thyroid cancer. The determination of benign and malignant thyroid nodules depends on the ultrasound results, which are based on whether the nodules have gravelly calcifications, whether the boundaries are clear, and whether there is abundant blood flow around them.
In general, if the following descriptions appear on the ultrasound report: a single nodule, gravelly calcifications in the nodule, or a TIRADS blood flow classification greater than IV, then a malignant nodule is highly suspected. On the other hand, thyroid nodules that do not show any of the above on ultrasound are usually benign, but it is still necessary to review the thyroid ultrasound in about six months.
In addition, the size of the nodule is not a criterion for differentiation between benign and malignant. The benignity or malignancy of nodules is not related to the size of nodules, whether the nodules are palpable or not, whether the nodules are single or multiple, or whether the nodules are combined with cystic changes.
4. What are the risks of thyroid nodules?
Most thyroid nodules are harmless and are benign lesions of the thyroid gland, just like a scar or a mole on our skin.
However, if the thyroid nodule is a solitary nodule with blood flow grade IV or higher, and the nodule contains gravel-like calcifications, it may be highly malignant and may gradually turn into thyroid cancer.
5.Does calcification of thyroid nodules indicate seriousness?
At present, it is recognized that only gritty calcifications in thyroid nodules on ultrasound are a sign of thyroid cancer, and about 55%-68% of thyroid cancer patients have these calcifications. The majority of these calcifications are general calcifications formed by inflammation and hematoma absorption.
6. Which thyroid nodules require fine needle aspiration (FNAB)?
Fine needle aspiration of the thyroid gland FNAB is the most reliable and valuable diagnostic method to distinguish benign from malignant nodules. In general, FNAB can be considered for any thyroid nodule > 1 cm in diameter. However, FNAB is not routinely performed in the following cases.
(1) Nodules with “hyperthyroid” manifestations confirmed by thyroid nuclide imaging.
(2) Nodules with ultrasound suggestive of pure cystic nature.
(3) Nodules that are already highly suspected to be malignant based on ultrasound images.
(4) Male.
(5) Rapid nodule growth.
(6) with persistent hoarseness and dysphonia and exclusion of vocal fold pathology (inflammation, polyps, etc.)
(7) With dysphagia or dyspnea.
(8) Irregular shape of the nodule and adhesions to surrounding tissues.
(9) Pathological enlargement of lymph nodes in the neck.
7.What are the methods of thyroid nodule surgery?
At present, most hospitals are using conventional small incision surgery, which is a transverse incision of about 4 cm in the neck. Some hospitals are also doing lumpectomy of thyroid nodules through the breast or axilla.
8. What are the risks of thyroid nodule surgery?
There are three common surgical risks as follows.
(1) Intra-operative and post-operative bleeding. Currently, due to the widespread use of ultrasonic knife in clinical practice, the incidence is generally very low, but once it occurs, especially in the case of post-operative bleeding, secondary surgery is required to stop the bleeding.
(2) Intraoperative injury to the recurrent laryngeal nerve and superior laryngeal nerve, the incidence of which is about 2% at home and abroad, is significantly correlated with the experience of the surgeon. Once injury to the laryngeal nerve occurs, it can lead to postoperative hoarseness and coughing, which is usually difficult to repair.
(3) Parathyroid gland injury, the incidence of which is lower than that of laryngeal nerve injury, is mainly related to the extent of intraoperative resection. The larger the size of the thyroid gland, the more thyroid tissue is removed or if thyroid cancer is diagnosed intraoperatively and the lymph nodes need to be cleared, the incidence is significantly higher.
9.Is it easy to recur after thyroid nodule surgery?
If the surgical excision is not complete, there is a high risk of residual hyperplastic thyroid tissue and microscopic nodules, and postoperative thyroxine suppression therapy has limited effect on the residual lesions, so the recurrence rate after surgery is high. If recurrence requires reoperation, the risk of surgery is 5 to 10 times higher than that of the initial surgery.
In foreign countries, a more aggressive approach is taken to bilateral nodular goiter, with total resection on one side of the main lesion and total or near-total resection on the opposite side, and normal thyroid function can be maintained after surgery with a small dose of thyroxine.
The advantages of this procedure are twofold: firstly, it completely avoids recurrence after surgery, and secondly, it avoids the risk and pain of reoperation for patients whose thyroid cancer is confirmed only after surgery. However, total thyroidectomy requires a high level of surgical requirements, and complete dissection of the bilateral recurrent laryngeal nerves and parathyroid glands is necessary to avoid serious complications.
10.What are the dietary requirements after thyroid nodule surgery?
To reduce recurrence after thyroid nodule surgery, you should eat less seafood and avoid iodine-rich foods, such as kelp, shrimp and nori.