Thyroid Nodules
What is a thyroid nodule? Perhaps you didn’t even know you had one until your doctor felt something in your neck. Perhaps you felt it yourself, or a family member or friend notices it. A thyroid nodule is basically a lump of abnormal tissue within an otherwise normal thyroid gland. They are usually benign, but since some of them are malignant, most nodules need to be evaluated to find which ones need more treatment. Nodules in the thyroid gland are more common than most people realize. They are more common the older one gets and the incidence climbs higher in the older population. At age 50, probably 50% of the population has a nodule that could be seen on ultrasound.
Once a nodule is identified, additional studies are usually ordered and you may be referred to a specialist. Fortunately, most nodules do not require surgery.
There are a few questions that need to be addressed before deciding to let it be:
Is the nodule producing excessive thyroid hormone?
This is usually easy to determine. If there is excess hormone being produced, you will usually have symptoms due to an abnormally high metabolism. These symptoms can include: unplanned weight loss, feeling hot when others are comfortable, a fast heart rate, diarrhea, anxiety or tremulousness, menstrual irregularities, among other things. There are simple blood tests to measure the thyroid hormone levels in your body that can answer this question as well. In many cases of overactive thyroid (hyperthyroidism), the gland will be enlarged. If the entire gland is involved, this is most often categorized as Graves’ disease. In other cases, there is a nodule which is responsible for all the excessive hormone production. This is usually categorized as “toxic nodular goiter”, or Plummer’s disease. In either case, it is not healthy to go untreated. There are a variety of treatment options, including medications, surgery, and a special type of radiation therapy. Surgery is most often recommended for patients diagnosed with toxic nodular goiter.
Is the nodule so large that it is causing blockage of the esophagus or trachea (windpipe), or affecting the voice (hoarseness)?
A single nodule is not usually so large as to cause such symptoms. These problems are more common if there are multiple nodules, or if the entire thyroid gland is diffusely enlarged. If you do have a nodule causing such symptoms, in most cases surgery would be recommended on the basis of relieving the symptoms.
Does the nodule contain cancer?
Although this is uncommon, we typically need to be sure that there is no cancer once a thyroid nodule is identified. This usually requires that a biopsy be done with a needle. At DeKalb Surgical Associates, this type of biopsy is usually done at the very first office visit, using ultrasound for guidance.
Needle Biopsy of Thyroid Nodule
A needle biopsy of a thyroid nodule can usually establish whether there is cancer or not. But you should understand the possible findings if a needle biopsy is done. There are about four possible findings:
- The nodule appears completely benign or is purely cystic. This is the result ~60% of the time. In such cases, no further treatment is usually necessary, though a follow-up office visit is typically planned, to see if there has been any change in the size of the nodule, or if any symptoms have developed. Sometimes a repeat biopsy is recommended for added assurance that the nodule is indeed benign.
- The nodule is definitely cancer. This is the result 5-10% of the time. In such cases, surgery will almost always be recommended. And in most cases, the recommended surgery will be a complete removal of the thyroid gland.
- The nodule consists of “follicular cells,” in which case, it may not be possible to tell if the nodule is cancer without surgical removal. These types of thyroid growths, follicular neoplasms, appear very similar whether benign or cancerous (malignant). In order to distinguish the cancerous ones from the benign ones, the pathologist must carefully examine the margins of the nodule under the microscope, and this requires complete removal of the nodule. So this is one of the situations where we still have to recommend surgery without knowing for sure whether you have cancer. Most of these follicular nodules will still be benign, but you will have to undergo surgery to prove this.
- The biopsy does not have enough cellular material to tell if it is cancer or not. The pathologist will call the biopsy “inadequate”, or “nondiagnostic”. In such cases, your doctor may recommend a second needle biopsy in hopes of getting sufficient cellular material. If a second biopsy yields the same result, surgery may be recommended in order to be sure there is no cancer. Fortunately, this result is uncommon, particularly if the biopsy is done by an experienced surgeon or another physician, and if the pathologist reading the slides is also highly experienced in interpreting thyroid biopsies.
Is there any reason to have a higher than usual suspicion of cancer?
There are some circumstances for which there may be a higher suspicion that there may be a cancer, and for which surgery is recommended even though cancer has not been diagnosed before surgery. If a nodule has increased dramatically in size, a recommendation for surgery may be made. If you have a history of radiation to your neck or body in the past, the risk of thyroid cancer in a nodule is increased. This may be the case for patients who might have been treated with radiation to the neck area for some other cancer in the past, such as Hodgkin’s disease, or a throat or breast cancer. Other patients might have been treated with radiation to the face for acne as a child. This was a treatment offered in the 1950’s before the associated risks were realized. And there are some who may have lived in the Chernobyl area when the nuclear meltdown occurred in 1986, exposing the surrounding population to high levels of radiation.
Surgery For a Thyroid Nodule
In most cases in which it is not yet known whether there is cancer, your surgeon will recommend removal of the entire thyroid lobe in which the nodule is contained. Since the thyroid gland is extremely vascular, attempts to remove just a portion of one of the lobes can be risky, mainly because of possible bleeding after surgery. In addition, if cancer is found, the risks for complications from further surgery are higher, if the surgeon has to remove the rest of the lobe from that side. Following the removal of just one of the thyroid lobes, there is no need to take any medication; the remaining lobe will almost always produce enough hormone for your body to have a normal metabolism.
If cancer is found in the nodule, your surgeon may recommend complete removal of the thyroid gland. The diagnosis is not usually confirmed until a few days after your operation, so this would require a return to the operating room. This would typically be done within a few weeks of your first operation. There are situations where furthering surgery will NOT be recommended. Your surgeon will discuss these options with you when necessary.
Your surgeon may recommend complete removal of the thyroid gland if it is known in advance that you have cancer based on the needle biopsy, or in some other cases as well. You may have a number of nodules involving both sides of the gland. You may have symptoms due to the size of the gland or the nodule(s). You may have had radiation to your neck in the past, which raises the suspicion for cancer. Your surgeon will discuss the reasons for his recommendation. Removal of the entire gland will require that you take a supplemental dose of thyroid hormone daily.
Risks of Surgery
There are risks associated with the removal of part or all of the thyroid gland.
- Bleeding. All glands in the body, including the thyroid, have a very rich blood supply. The thyroid gland has blood vessels entering the upper and lower pole of each lobe. These must be securely controlled during surgery to avoid bleeding after surgery.
If bleeding occurs after thyroid surgery, a relatively small amount of blood can cause pressure on the airway, and this, in turn, can make it hard or even impossible to breathe. Even with good control of the blood vessels during surgery, some patients may rarely have trouble breathing in the first 24 hours after surgery due to bleeding. In most such cases, you must go back to the operating room emergently in order to remove the blood and regain control of the blood vessels. This can be a life-threatening event but is fortunately extremely uncommon.
- Injury to nerves to the voice box (larynx). There is a nerve behind each thyroid lobe that travels upward through the neck to innervate the right and left vocal cords. These nerves are directly adjacent to the underside of the thyroid and so they are vulnerable to injury. These nerves are called the recurrent laryngeal nerves.
The likelihood of injury during thyroid surgery is usually quoted as about 1%. If the nerve is actually divided, you almost certainly will have a change in your voice afterward, typically with hoarseness, and inability to speak above a whisper. If both nerves are injured, you will likely have trouble even taking a good breath, because of the floppy vocal cords blocking air flow.Fortunately, such injuries rarely occur, but they can obviously have a major impact on your life. If such an injury occurs, it is usually evident to the surgeon during the operation. There are some techniques to repair the divided nerve, but the results are variable. There are other options to consider at a later date, to help improve the hoarseness, and in some cases, the voice can improve considerably without other intervention, depending on the extent of the injury.
- Injury to the parathyroid glands. There are two tiny glands behind each thyroid lobe called parathyroid glands which control the level of calcium in the bloodstream.
The calcium level in the blood must be maintained within a very tight range in order for many cellular processes to run normally. These tiny glands receive their blood supply from the same blood vessels that supply the thyroid and, therefore, can be injured unintentionally during thyroid surgery. Injury to just one parathyroid gland would not cause a problem with your calcium since each gland by itself could supply enough of its hormone for the body.
If all four glands are injured, your calcium level can drop too low soon after surgery. Since there are two glands on each side, there is really no risk for this problem if only one thyroid lobe is being removed. Even if your entire thyroid is being removed, the risk for this problem is low. If your calcium level drops after surgery, you may experience symptoms of numbness or a tingling around your mouth or in your fingers and toes. If the calcium level drops further you may develop some muscle cramping and spasms, which can even be life-threatening if not treated. The calcium level can easily be checked with a simple blood test after surgery. You may receive some supplemental calcium after surgery to decrease the likelihood of having any of these symptoms. Most patients who have these symptoms after surgery do not have a permanent low calcium problem, and the symptoms if present usually goes away without the need for ongoing calcium supplements.
For the rare patient with a permanent 4 gland parathyroid injury (hypoparathyroidism), your calcium level must be maintained with supplements of calcium and vitamin D every day. The risks of removing just one lobe of the thyroid are clearly less than the risks for removing both lobes so we remove the affected side unless there is clearly a need for total thyroidectomy. In the majority of cases of surgery for a thyroid nodule, this may be the preferred option (even though a second operation could be necessary when cancer is ultimately diagnosed).
Goiter
A goiter is an abnormal enlargement of the thyroid gland in your neck. The word goiter derives from the Latin word “guttur,” which means “throat”. When using the word goiter, it is usually implied that the enlargement of the thyroid is enough to be visible to someone else. In fact, goiters can become absolutely gigantic, but usually people become aware of them when they are much smaller.
Why does the goiter enlarge?
Years ago, goiters were much more common. In days gone by, there were many geographic locations where there was very little iodine in the diet. The thyroid gland needs iodine in order to make thyroid hormone. If there is not enough iodine being absorbed, then another gland, called the pituitary gland, produces a different hormone (“thyroid stimulating hormone, or TSH) that stimulates the thyroid gland to produce more hormone. This TSH also stimulates the growth of the thyroid gland, which can then cause a goiter. If an entire population gets inadequate iodine in their diet, there may be 5% or more of the people who develop a goiter. There are still places in the world where this occurs, usually in secluded mountainous areas. Since seafood typically contains iodine, a deficiency is uncommon in coastal areas.
In the early 1900s, iodide became a standard additive in table salt, and as a result, it is very uncommon to have a deficiency of iodine in the diet in any Western country. Today, a deficiency of iodine could be a problem since certain heart conditions are treated with low salt or no salt diets. If a goiter has developed because of an iodine deficiency, it will usually shrink back with iodine replacement, unless the deficiency has continued for more than about 5 years.
One might think that if the thyroid is so enlarged that it must be making way too much of its hormone, but that is usually not the case. If the thyroid is large because of an iodine deficiency, the hormone production might even be on the low side.
What should be done if you have a goiter?
It might not be necessary to do anything, other than some basic evaluations. Primary care physicians may do an evaluation themselves or they may refer you to an endocrinologist or a surgeon with experience in thyroid disorders.
During the evaluation, you will be asked about any symptoms that might suggest excess or insufficient thyroid hormone production or whether the size of the thyroid is affecting your ability to breathe, swallow, or talk normally. They will examine your neck to see how large the thyroid is, and whether it appears to be compressing your airway. If you have any hoarseness, they will want to examine your vocal cords, which ideally requires the use of a flexible lighted scope placed into the back of your throat.
A goiter can sometimes place pressure on your airway, making it difficult to breathe at times. It can also compress your esophagus, enough to cause food to get held up in your neck for a while before passing through. A goiter can also affect your voice by compressing the nerves that maintain the tautness of your vocal cords. It can also partially occlude the large arteries and veins carrying blood to and from your brain.
An ultrasound of your thyroid gland will likely also be done, which can show the presence or absence of nodules. A blood test will likely be drawn to measure the level of the thyroid hormone, as well as the TSH (thyroid stimulating hormone) in your blood stream. Possible scans may include a chest x-ray of your neck or a CAT scan. This can help determine how large the goiter is; in some cases, the gland can actually grow downward into your chest cavity. This is called a “substernal goiter”, which more often requires surgery. If there are any nodules seen in the goiter, then a needle biopsy may be recommended. A needle biopsy is usually only recommended when one needs to be sure there is no cancer present.
With these tests, a decision can then usually be made as to whether surgery should be done. If you experience no symptoms from the goiter, there is no overactivity in any part of the gland, and no added concern for occult cancer, then it can be left alone. Some patients may not really have any symptoms, but would just prefer to have it removed. This is a reasonable option, but it is important to be aware that no surgical procedure is without risk, and so one needs to consider the risks of the surgery very carefully, more so if the reason for the surgery is really a “cosmetic” one.
If your goiter is overproducing thyroid hormone or if it is causing some of the symptoms described above, then surgery may be recommended as treatment.
Surgery for a Goiter
There are two basic surgical procedures that might be recommended for someone with a goiter. One side of the gland may be removed (thyroid lobectomy) or the entire thyroid may be removed (total thyroidectomy), depending on the size of the goiter and other factors. If the goiter’s enlargement is limited almost completely to just one side of the thyroid, one might consider either option.
Total Thyroidectomy
Advantages:
- There is virtually no risk that you might regrow a goiter on the other side in the future.
- If cancer happens to be found in the gland when the pathologist examines it, there would not be any need to return to the operating room to remove the remaining thyroid gland.
Disadvantages:
- Risk of injury to the two nerves which innervate the two vocal cords, one behind each thyroid lobe.
- Risk of bleeding from the blood vessels on each side of the neck that supplies blood to the thyroid gland.
- Risk of injury to one or more of the parathyroid glands behind the thyroid gland. These parathyroid glands control the calcium level in your body. Just one parathyroid gland can provide enough hormone production for the entire body, but if all four glands are injured, your calcium level can drop dangerously low.
- A thyroid hormone pill is required every day. Without this hormone, your metabolism will become very slow and if untreated can be life-threatening.
Thyroid Lobectomy
Advantages:
- Surgical risks are minimized. The risk of nerve injury is limited to just the side being operated on. The bleeding risk is also limited to just one side. There is virtually no risk for low calcium levels from parathyroid gland injury since there are two glands which will not be at risk of any injury.
- There is rarely any need for thyroid hormone replacement with thyroid lobectomy since the remaining gland usually produces more than enough hormone.
Disadvantages:
- If cancer happens to be found in the removed lobe, it is very likely a second operation is needed to remove the rest of the gland.
- It is possible to develop a new goiter in the remaining thyroid lobe which could eventually require a second operation in the future.
Thyroid Cancer
Fortunately, cancers do not occur in the thyroid gland very often. It is estimated that in the entire US there are about 45,000 patients with newly diagnosed thyroid cancer each year. There are about 1,700 people who die of thyroid cancer each year. Compare these statistics with lung cancer, with over 200,000 people diagnosed each year, and over 150,000 deaths.
It can be common to find small lumps or nodules in the thyroid gland. Most new nodules are NOT cancer, but the only way to know that yours is not cancer is to either have a needle biopsy performed, or have it removed surgically.
There are times when a needle biopsy of a nodule definitely shows cancer and other times when it is necessary to do an operation to know for sure. If you have had a needle biopsy and are told that surgery will be necessary to know for sure, it may be worthwhile to be certain the slides which were made at the time of biopsy have been reviewed by someone who is an expert in “cytopathology.” We have seen cases where surgery was recommended, but after we reviewed the slides, surgery was able to be avoided.
If surgery is necessary, it usually involves staying overnight in the hospital only one night. Depending on the situation, your surgeon may recommend removal of just half of the thyroid gland, or nearly all of it. If it is already known for certain that there is cancer, in most cases all of the thyroid glands will be removed, and you’ll need to be on thyroid replacement medication after the surgery. Fortunately, this is easy to take, with virtually no side effects. But the levels of hormones in your body will have to be checked occasionally to be sure the dose your prescribed is correct. In many cases after thyroid removal for cancer, you may be referred to an endocrinologist to undergo treatment with radioactive iodine. This is the treatment which helps to completely eradicate thyroid cancer cells in the neck or elsewhere in the body.
Thyroid surgery carries some risks, but in most cases, you can go home the next day, and resume your normal activities and 1-2 weeks.
The risks of thyroid surgery are:
- Risk of injury to the two nerves which innervate the two vocal cords, one behind each thyroid lobe (called the “recurrent laryngeal nerves”).
- Risk of bleeding from the blood vessels on each side of the neck that supplies blood to the thyroid gland.
- Risk of injury to one or more of the parathyroid glands behind the thyroid gland. These parathyroid glands control the calcium level in your body. Just one parathyroid gland can provide enough hormone production for the entire body, but if all four glands are injured, your calcium level can drop dangerously low.
- With a total thyroidectomy, a thyroid hormone pill is required every day. Without this hormone, your metabolism will become very slow, and if untreated can be life-threatening.