Thyroid Nodule Overview
The Diagnosis, Meaning, and Treatment of Thyroid Nodules
Thyroid nodules are most commonly found when a doctor examines a patient's neck, feeling the thyroid gland. Sometimes thyroid nodules are found when a patient gets x-rays or scans of the neck for some other reason. Sometimes it is a screening x-ray or scan for carotid arteries or neck pain that shows nodules in the thyroid. Thyroid nodules that are large, develop in women with thin necks, or are present in the middle portion of the thyroid gland (called the isthmus) may be visible and discovered as a lump in the neck.
Thyroid Nodule Symptoms: Uncommon but can Happen
Thyroid nodule patients usually have no symptoms, but when they do have symptoms they are most commonly:
- A lump in the neck (thyroid)
- Uncomfortable pressure sensation on the breathing tube (trachea)
- A sense of feeling like they need to swallow something or difficulty swallowing
- Discomfort in the neck
Thyroid nodules may also rarely produce the thyroid hormone, thyroxine, in excess. This is uncommon but the reason why all patients with thyroid nodules should have a blood test for thyroid stimulating hormone (TSH). Thyroid nodules that produce extra thyroid hormone can cause symptoms of hyperthyroidism which include:
- Unexplained weight loss
- Heat intolerance
- Tremor
- Nervousness
- Rapid or irregular heart rate
We have an entire page on thyroid nodule symptoms. It is one of the best pages of this website and discusses the 7 symptoms caused by nodules and what to do about each type of nodule. When you are done reading this page, go to our symptoms of thyroid nodules page!
Most thyroid nodules are benign (non-cancerous), but some thyroid nodules are thyroid cancer
A small percentage of thyroid nodules are malignant (cancer). You can not tell if a thyroid nodule is malignant due to symptoms or lack of symptoms. Those thyroid nodules that are cancer, tend to be very slow growing. The very rare thyroid nodule that is an aggressive thyroid cancer may present with a large thyroid mass, firm or non-mobile mass or even change in vocal quality. Only in these very rare circumstances, when the thyroid nodule is an aggressive thyroid cancer, is there an urgent need for prompt evaluation and thyroid cancer surgery by the most highly experienced thyroid cancer surgeon. Otherwise, thoughtful evaluation and consultation by an expert thyroid cancer surgeon is required for thyroid nodules. In other words, the vast majority of thyroid nodules can be worked up without a sense of urgency. Don't make rash, quick decisions--thyroid nodules in almost all cases provide plenty of time to get figured out. So chill if you are here because you just found out you have a thyroid nodule. Read and understand what this means. And realize that in almost all cases, you have time to figure this out! We have created a Thyroid Nodule and Cancer Guide app to help, you can download the Apple or Android app to better understand your thyroid nodule, determine what you "next steps" are, and examine your risk of thyroid cancer.
Nate's Nodules on YouTube
Dr. Nate Walsh, Senior Surgeon at the Clayman Thyroid Center & Hospital for Endorine Surgery, has an entire YouTube channel dedicated to thyroid nodules. Dr. Walsh operates on a significant number of patients with thyroid nodules, and on his channel he covers frequently asked questions, interesting cases, and more. Check out the Nate's Nodules YouTube Channel here.Watch a video at https://www.youtube.com/embed/92gv34o-46A
Thyroid Nodules: Potential Causes
Several conditions may cause or predispose to the development of thyroid nodules including:
Iodine deficiencyDiets deficient in iodine can predispose individuals for the development of thyroid nodules. Portions of the world continue to lack iodine in their diets however in the United States, the presence of iodine in our daily diets makes this an unlikely cause for thyroid nodules.
Overgrowth of normal thyroid tissueThe reason why these thyroid nodules occur is not well understood. These thyroid nodules are commonly called follicular adenomas or thyroid adenomas. (the follicular cell is a normal appearing thyroid cell). Follicular adenomas are clearly not cancerous and are not worrisome and do not require removal except if they are symptomatic due to their size. The rare follicular adenoma or thyroid adenoma will overproduce thyroid hormone and be the cause of hyperthyroidism. For some reason these excessive thyroid hormone producing adenomas lose their ability to be regulated by the pituitary glands production of Thyroid Stimulating Hormone (TSH).
Thyroid cystsThyroid cysts are fluid filled cavities caused by degenerating thyroid adenomas, congenital cysts, or overproduction of a fluid produced by the thyroid called colloid.
Inflammatory diseases of the thyroid (called thyroiditis)Hashimoto’s thyroiditis or Hashimoto’s disease is a chronic inflammatory condition of the thyroid gland caused by an autoimmune event where the patient develops antibodies to thyroglobulin (a normal protein produced by the thyroid gland). Long standing Hashimoto’s thyroiditis is frequently associated with diseased thyroid hormone production call hypothyroidism. Hashimoto’s thyroiditis may also be associated with thyroid pseudo-nodule formation. These pseudo nodules are not concerning thyroid nodules. Pseudo nodules found on ultrasound in thyroiditis patients will come and go based upon unknown issues.
Multinodular disease of the thyroid (also called Multinodular Goiter or just “Goiter”)Multinodular goiter is a thyroid gland which contains multiple thyroid nodules. The cause of multinodular goiter is not known but in some instances there may be a strong family history of goiters. Multinodular goiters can be quite massive and extend throughout the neck and well into the chest cavity.
Thyroid CancerAlthough the likelihood that a thyroid nodule is a cancer is quite low, the following are associated with an increased malignant risk:
- Age less than 30 years of age
- Age greater than 50 years of age
- Men greater than women
- A positive family history of thyroid cancer
- A positive family history of other endocrine cancers
- A history of radiation exposure
- Larger thyroid nodules
- Vocal cord paralysis (hoarseness)
Thyroid Nodule: Evaluation and Tests
The following are a list of tests that are required in the evaluation of a patient with a thyroid nodule.
- Complete Medical History and Physical Examination
- Ultrasound
- Blood Tests
- TSH
- T3 and T4
- Thyroglobulin (we obtain but not all doctors do so)
- Thyroglobulin Antibody (we obtain because it lets us know if there is an underlying inflammatory condition of the thyroid)
- Laryngoscopy (looking at the voice box)
- Ultrasound guided Fine Needle Aspiration (FNA)
If there is a suspicion that you may have a thyroid nodule, your health care professional will want to know your complete medical history. You will be asked questions about your possible risk factors, symptoms, and any other health problems or concerns. If someone in your family has had a diagnosis of thyroid cancer or other endocrine cancer, these are important factors.
Your doctor will examine you to get more information about possible signs of thyroid cancer and other health problems. During the exam, the doctor will pay special attention to the size and firmness of your thyroid and any enlarged lymph nodes in your neck. Examination of your voice box is part of the physical examination obtained by the surgeon for any thyroid lump. A small lighted microscope is used to look at the voice box to determine how the vocal cords of the voice box are functioning. Even though a patient does not report change in their voice does not insure that the vocal cords are working normally. A vocal cord that is paralyzed greatly increases the concern that a thyroid nodule may be a cancer.
Thyroid Nodule: When is a Radioiodine Scan Ordered?
Only in instances where the blood test to examine the thyroid nodule patient demonstrates that hyperthyroidism is present in addition to the presence of the thyroid nodule, is a radioiodine scan (thyroid scan) indicated. In these cases, the thyroid stimulating hormone (TSH) will be very low. The thyroid nodule patient may or may not have recognized symptoms of hyperthyroidism. If the TSH level is normal, there is absolutely no contemporary indication for a thyroid scan.
During the thyroid scan, the patient will be given a small amount of radioactive iodine in their vein and a special imaging camera is utilized to determine how much iodine is taken up by the thyroid gland and if the nodule takes up iodine relative to the remainder of the thyroid gland (this is called a “hot nodule”). If the nodule has less iodine uptake than the rest of the thyroid gland, then the thyroid nodule is called a “cold nodule”.
Hot nodules are almost always non-cancerous but the preferred management of hot nodules is frequently surgery since it is a clear, safe and 100% effective therapy for the hyperthyroidism. Cold nodules have a higher incidence of malignancy than hot nodules but still most are benign.