GOITER
The term “goiter” simply refers to the abnormal enlargement of the thyroid gland.
It is important to know that the presence of a goiter does not necessarily mean that the thyroid gland is malfunctioning. A goiter can occur in a gland that is producing too much hormone (hyperthyroidism), too little hormone (hypothyroidism), or the correct amount of hormone (euthyroidism).
A goiter indicates there is a condition present which is causing the thyroid to grow abnormally.
- One of the most common causes of goiter formation worldwide is iodine deficiency.
- Hashimoto’s thyroiditis is common cause of goiter formation. This is an autoimmune condition in which there is destruction of the thyroid gland by one’s own immune system.
- Another common cause of goiter is Graves’ disease. Graves’ disease produces a goiter and hyperthyroidism.
- Multinodular goiters are another common cause of goiters. Individuals with this disorder have one or more nodules within the gland which cause thyroid enlargement.
- In addition to the common causes of goiter, there are many other less common causes. Some of these are due to genetic defects, others are related to injury or infections in the thyroid, and some are due to tumours (both cancerous and benign tumours).
- The diagnosis of a goiter is usually made at the time of a physical examination when an enlargement of the thyroid is found.
- However, the presence of a goiter indicates there is an abnormality of the thyroid gland. Therefore, it is important to determine the cause of the goiter.
- As a first step, you will likely have thyroid function tests to determine if your thyroid is underactive or overactive
- Any subsequent tests performed will be dependent upon the results of the thyroid function tests.
- If the thyroid is diffusely enlarged and you are hyperthyroid, your doctor will likely proceed with tests to help diagnose Graves’ Disease.
- If you are hypothyroid, you may have Hashimoto’s Thyroiditis (see Hypothyroidism) and you may get additional blood tests to confirm this diagnosis.
- Other tests used to help diagnose the cause of the goiter may include a radioactive iodine scan, thyroid ultrasound, or a fine needle aspiration biopsy (see Thyroid Nodule).
- The treatment will depend upon the cause of the goiter.
- If the goiter was due to a deficiency of iodine in the diet. You will be given iodine supplementation given in preparations to take by mouth. This will lead to a reduction in the size of the goiter, but often the goiter will not completely resolve.
- If the goiter is due to Hashimoto’s Thyroiditis, and you are hypothyroid, you will be given thyroid hormone supplement as a daily pill.
- This treatment will restore your thyroid hormone levels to normal, but does not usually make the goiter go completely away. While the goiter may get smaller, sometimes there is too much scar tissue in the gland to allow it to get much smaller.
- However, thyroid hormone treatment will usually prevent it from getting any larger. Although appropriate in some individuals, surgery is usually not routine treatment of thyroiditis.
- If the goiter is due to hyperthyroidism, the treatment will depend upon the cause of the hyperthyroidism (see Hyperthyroidism).
- For some causes of hyperthyroidism, the treatment may lead to a disappearance of the goiter. For example, treatment of Graves’ disease with radioactive iodine usually leads to a decrease or disappearance of the goiter.
- Many goiters, such as the multinodular goiter, are associated with normal levels of thyroid hormone in the blood.
- These goiters usually do not require any specific treatment after the appropriate diagnosis is made. If no specific treatment is suggested, you may be warned that you are at risk for becoming hypothyroid or hyperthyroid in the future.
- However, if there are problems associated with the size of the thyroid per se, such as the goiter getting so large that it constricts the airway, your doctor may suggest that the goiter be treated by surgical removal.
- Whatever the cause, it is important to have regular (annual) monitoring when diagnosed with a goiter.
Hypothyroidism
Hypothyroidism is an underactive thyroid gland. Hypothyroidism means that the thyroid gland can’t make enough thyroid hormone to keep the body running normally.
People are hypothyroid if they have too little thyroid hormone in the blood.
When thyroid hormone levels are too low, the body’s cells can’t get enough thyroid hormone and the body’s processes start slowing down. As the body slows, you may notice that
- you feel colder,
- you tire more easily,
- your skin is getting drier,
- you’re becoming forgetful and depressed,
- and you’ve started getting constipated.
Because the symptoms are so variable and nonspecific, the only way to know for sure whether you have hypothyroidism is with a simple blood test for TSH.
- There is no cure for hypothyroidism, and most patients have it for life.
- There are exceptions: many patients with viral thyroiditis have their thyroid function return to normal, as do some patients with thyroiditis after pregnancy.
- Hypothyroidism may become more or less severe, and your dose of thyroxine may need to change over time.
- You have to make a lifetime commitment to treatment.
- But if you take your pills every day and work with your doctor to get and keep your thyroxine dose right, you should be able to keep your hypothyroidism well controlled throughout your life.
- Your symptoms should disappear and the serious effects of low thyroid hormone should improve.
There can be many reasons why the cells in the thyroid gland can’t make enough thyroid hormone. Here are the major causes, from the most to the least common.
- Autoimmune disease. This is more common in women than men. Autoimmune thyroiditis can begin suddenly or it can develop slowly over years. The most common forms are Hashimoto’s thyroiditis and atrophic thyroiditis.
- Surgical removal of part or all of the thyroid gland.
- Radiation treatment. Some people with Graves’ disease, nodular goiter, or thyroid cancer are treated with radioactive iodine (I-131) for the purpose of destroying their thyroid gland.
- Congenital hypothyroidism (hypothyroidism that a baby is born with).
- Thyroiditis can make the thyroid dump its whole supply of stored thyroid hormone into the blood at once, causing brief hyperthyroidism (too much thyroid activity); then the thyroid becomes underactive.
- Some drugs are most likely to trigger hypothyroidism in patients who have a genetic tendency to autoimmune thyroid disease.
- Too much or too little iodine. Taking in too much iodine can cause or worsen hypothyroidism.
- Damage to the pituitary gland.
The correct diagnosis of hypothyroidism depends on the following:
Symptoms.
- Hypothyroidism doesn’t have any characteristic symptoms.
- One way to help figure out whether your symptoms are due to hypothyroidism is to think about whether you’ve always had the symptom (hypothyroidism is less likely) or whether the symptom is a change from the way you used to feel (hypothyroidism is more likely).
Medical and family history.
- about changes in your health that suggest that your body is slowing down;
- if you’ve ever had thyroid surgery;
- if you’ve ever had radiation to your neck to treat cancer;
- if you’re taking any of the medicines that can cause hypothyroidism
- whether any of your family members have thyroid disease..
Physical exam.
The doctor will check your thyroid gland and look for changes such as:
- dry skin,
- swelling,
- slower reflexes,
- and a slower heart rate.
Blood tests.
- TSH (thyroid-stimulating hormone) test. This is the most important and sensitive test for hypothyroidism. An abnormally high TSH means hypothyroidism.
- T4 tests.
THYROXINE (T4) REPLACEMENT.
- Hypothyroidism can’t be cured.
- But in almost every patient, hypothyroidism can be completely controlled.
- It is treated by replacing the amount of hormone that your own thyroid can no longer make, to bring your T4 and TSH levels back to normal levels.
- So even if your thyroid gland can’t work right, T4 replacement can restore your body’s thyroid hormone levels and your body’s function.
- For the few patients who do not feel completely normal taking a synthetic preparation of T4 alone, the addition of T3 may be of benefit.
SIDE EFFECTS AND COMPLICATIONS.
- The only dangers of thyroxine are caused by taking too little or too much. If you take too little, your hypothyroidism will continue. If you take too much, you’ll develop the symptoms of hyperthyroidism—an overactive thyroid gland.
FOLLOW-UP
- You’ll need to have your TSH checked 6 to 10 weeks after a thyroxine dose change.
- You may need tests more often if you’re pregnant or you’re taking a medicine that interferes with your body’s ability to use thyroxine.
- The goal of treatment is to get and keep your TSH in the normal range.
- Once you’ve settled into a thyroxine dose, you can return for TSH tests about once a year.
YOU NEED TO RETURN SOONER IF ANY OF THE FOLLOWING APPLY TO YOU:
- Your symptoms return or get worse.
- You gain or lose a lot of weight
- You start or stop taking a drug that can interfere with absorbing thyroxine (such as certain antacids, calcium supplements and iron tablets), or you change your dose of such a drug.
- You’re not taking all your thyroxine pills. Tell your doctor honestly how many pills you’ve missed.
Hyperthyroidism
The term hyperthyroidism refers to any condition in which there is too much thyroid hormone produced in the body.
In other words, the thyroid gland is overactive.
Another term that you might hear for this problem is thyrotoxicosis, which refers to high thyroid hormone levels in the blood stream, irrespective of their source.
Thyroid hormone plays a significant role in the pace of many processes in the body. These processes are called your metabolism. If there is too much thyroid hormone, every function of the body tends to speed up. It is not surprising then that some of the symptoms of hyperthyroidism are
- nervousness,
- irritability,
- increased sweating,
- heart racing,
- hand tremors,
- anxiety,
- difficulty sleeping,
- thinning of your skin,
- fine brittle hair
- and weakness in your muscles—especially in the upper arms and thighs.
- You may have more frequent bowel movements, but diarrhoea is uncommon.
- You may lose weight despite a good appetite
- and, for women, menstrual flow may lighten and menstrual periods may occur less often.
- Since hyperthyroidism increases your metabolism, many individuals initially have a lot of energy.
- However, as the hyperthyroidism continues, the body tends to break down, so being tired is very common.
- In Graves’ Disease which is the most common form of hyperthyroidism, the eyes may look enlarged because the upper lids are elevated. Sometimes, one or both eyes may bulge.
- Some patients have swelling of the front of the neck from an enlarged thyroid gland (a goiter).
- The most common cause (in more than 70% of people) is overproduction of thyroid hormone by the entire thyroid gland.
- This condition is also known as Graves’ disease.
- Graves’ disease is caused by antibodies in the blood that turn on the thyroid and cause it to grow and secrete too much thyroid hormone.
- Another type of hyperthyroidism is characterized by one or more nodules or lumps in the thyroid that may gradually grow and increase their activity so that the total output of thyroid hormone into the blood is greater than normal. This condition is known as toxic nodular or multinodular goiter.
- Also, people may temporarily have symptoms of hyperthyroidism if they have a condition called thyroiditis. This condition is caused by a problem with the immune system or a viral infection that causes the gland to leak stored thyroid hormone.
- The same symptoms can also be caused by taking too much thyroid hormone in tablet form.
- In these last two forms, there is excess thyroid hormone but the thyroid is not overactive.
Physical Examination
- If your physician suspects that you have hyperthyroidism, diagnosis is usually a simple matter.
- A physical examination usually detects an enlarged thyroid gland and a rapid pulse.
- The physician will also look for moist, smooth skin and a tremor of your fingers.
- Your reflexes are likely to be fast, and your eyes may have some abnormalities if you have Graves’ disease.
Blood Tests
- The diagnosis of hyperthyroidism will be confirmed by laboratory tests that measure the amount of thyroid hormones— thyroxine (T4) and triiodothyronine (T3)—and thyroid-stimulating hormone (TSH) in your blood.
- A high level of thyroid hormone in the blood plus a low level of TSH is common with an overactive thyroid gland.
- If blood tests show that your thyroid is overactive, your doctor may want to measure levels of thyrotropin receptor antibodies (TRAbs), which when elevated confirm the diagnosis of Grave’s disease.
Imaging
- Your doctor may also want to obtain a picture of your thyroid (a thyroid scan). The scan will find out if your entire thyroid gland is overactive or whether you have a toxic nodular goiter or thyroiditis (thyroid inflammation).
- A test that measures the ability of the gland to collect iodine (a thyroid uptake) may be done at the same time.
No single treatment is best for all patients with hyperthyroidism. The appropriate choice of treatment will be influenced by:
- your age,
- the type of hyperthyroidism that you have,
- the severity of your hyperthyroidism,
- other medical conditions that may be affecting your health,
- and your own preference.
Antithyroid Drugs:
- In about 20% to 30% of patients with Graves’ disease, treatment with antithyroid drugs for a period of 12 to 18 months will result in prolonged remission of the disease.
- For patients with toxic nodular or multinodular goiter, antithyroid drugs are sometimes used in preparation for either radioiodine treatment or surgery.
- Antithyroid drugs cause allergic reactions in about 5% of patients who take them.
- A rarer (occurring in 1 of 500 patients), but more serious side effect is a decrease in the number of white blood cells. Such a decrease can lower your resistance to infection.
- Very rarely, these white blood cells disappear completely, producing a condition known as agranulocytosis, a potentially fatal problem if a serious infection occurs.
- If you are taking one of these drugs and develop a fever or sore throat, you should stop the drug immediately and have a white blood cell count that day.
- Even if the drug has lowered your white blood cell count, the count will return to normal if the drug is stopped immediately.
- Liver damage is another very rare side effect. You should stop the medicine and call your doctor if you develop yellow eyes, dark urine, severe fatigue, or abdominal pain.
Radioactive Iodine:
- Another way to treat hyperthyroidism is to damage or destroy the thyroid cells that make thyroid hormone.
- The radioactive iodine used in this treatment is administered by mouth, usually in a small capsule that is taken just once. once swallowed, the radioactive iodine gets into your bloodstream and quickly is taken up by the overactive thyroid cells.
- Radioactive iodine has been used to treat patients for hyperthyroidism for over 60 years and has been shown to be generally safe.
- Importantly, there has been no clear increase in cancer in hyperthyroid patients that have been treated with radioactive iodine.
- As a result, in the United States more than 70% of adults who develop hyperthyroidism are treated with radioactive iodine.
- More and more children over the age of 5 are also being safely treated with radioiodine.
Surgery:
- Your hyperthyroidism can be permanently cured by surgical removal of all or most of your thyroid gland.
- After your thyroid gland is removed, the source of your hyperthyroidism is gone and you will become hypothyroid.
- As with hypothyroidism that develops after radioiodine treatment, your thyroid hormone levels can be restored to normal by treatment once a day with a thyroid hormone supplement.
Beta-Blockers:
- No matter which of these three methods of treatment are used for your hyperthyroidism, your physician may prescribe a class of drugs known as beta-blockers that block the action of thyroid hormone on your body.
- They usually make you feel better within hours to days, even though they do not change the high levels of thyroid hormone in your blood.
- These drugs may be extremely helpful in slowing down your heart rate and reducing the symptoms of palpitations, shakes, and nervousness until one of the other forms of treatment has a chance to take effect.
Because hyperthyroidism, especially Graves’ disease, may run in families, examinations of the members of your family may reveal other individuals with thyroid problems.
Thyroid Nodules
The term thyroid nodule refers to an abnormal growth of thyroid cells that forms a lump within the thyroid gland.
Although the vast majority of thyroid nodules are benign (noncancerous), a small proportion of thyroid nodules do contain thyroid cancer.
In order to diagnose and treat thyroid cancer at the earliest stage, most thyroid nodules need some type of evaluation.
- Noticing a lump in their neck while looking in a mirror, buttoning their collar, or fastening a necklace.
- Thyroid nodules may produce excess amounts of thyroid hormone causing hyperthyroidism (see Hyperthyroidism).
- However, most thyroid nodules, including those that cancerous, are actually non-functioning, meaning tests like TSH are normal.
- If a nodule is large enough to compress the windpipe or esophagus, it may cause difficulty with breathing, swallowing, or cause a “tickle in the throat”.
- Even less commonly, hoarseness can be caused if the nodule invades the nerve that controls the vocal cords but this is usually related to thyroid cancer.
The important points to remember are the following:
- Thyroid nodules generally do not cause symptoms.
- Thyroid tests are most typically normal—even when cancer is present in a nodule.
- The best way to find a thyroid nodule is to make sure your doctor checks your neck!
- We do not know what causes most thyroid nodules but they are extremely common.
- By age 60, about one-half of all people have a thyroid nodule that can be found either through examination or with imaging.
- Fortunately, over 90% of such nodules are benign.
- Hashimoto’s thyroiditis, which is the most common cause of hypothyroidism (see Hypothyroidism), is associated with an increased risk of thyroid nodules.
- Iodine deficiency, is also known to cause thyroid nodules.
Clinical examination:
- Once the nodule is discovered, your doctor will try to determine whether the rest of your thyroid is healthy or whether the entire thyroid gland has been affected by a more general condition such as hyperthyroidism or hypothyroidism.
- Your physician will feel the thyroid to see whether the entire gland is enlarged and whether a single or multiple nodule are present.
Blood Tests:
- The initial laboratory tests may include measurement of thyroid hormone (thyroxine, or T4) and thyroid-stimulating hormone (TSH) in your blood to determine whether your thyroid is functioning normally.
Since it’s usually not possible to determine whether a thyroid nodule is cancerous by physical examination and blood tests alone, the evaluation of the thyroid nodules often includes specialized tests such as thyroid ultrasonography and fine needle biopsy.
Thyroid Ultrasound:
- Thyroid ultrasound is a key tool for thyroid nodule evaluation.
- This very accurate test can easily determine if a nodule is solid or fluid filled (cystic), and it can determine the precise size of the nodule.
- Ultrasound can help identify suspicious nodules since some ultrasound characteristics of thyroid nodules are more frequent in thyroid cancer than in noncancerous nodules.
- Thyroid ultrasound can identify nodules that are too small to feel during a physical examination.
- Ultrasound can also be used to accurately guide a needle directly into a nodule when your doctor thinks a fine needle biopsy is needed.
- Once the initial evaluation is completed, thyroid ultrasound can be used to keep an eye on thyroid nodules that do not require surgery to determine if they are growing or shrinking over time.
THYROID FINE NEEDLE ASPIRATION BIOPSY (FNA OR FNAB):
- A fine needle biopsy of a thyroid nodule may sound frightening, but the needle used is very small and a local anesthetic may not even be necessary.
- This simple procedure is often done in the doctor’s office.
- Ordinarily, several samples will be taken from different parts of the nodule to give your doctor the best chance of finding cancerous cells if they are present. The cells are then examined under a microscope by a pathologist.
The report of a thyroid fine needle biopsy will usually indicate one of the following findings:
- The nodule is benign (noncancerous).
- This result is obtained in up to 80% of biopsies.
- Generally, benign thyroid nodules do not need to be removed unless they are causing symptoms like choking or difficulty swallowing.
- Follow up ultrasound exams are important.
- Occasionally, another biopsy may be required in the future, especially if the nodule grows over time.
- The nodule is malignant (cancerous) or suspicious for malignancy.
- A malignant result is obtained in about 5% of biopsies and is most often due to papillary cancer, which is the most common type of thyroid cancer.
- A suspicious biopsy has a 50-75% risk of cancer in the nodule.
- These diagnoses require surgical removal of the thyroid after consultation with your Doctor.
- The nodule is indeterminate.
- This is actually a group of several diagnoses that may occur in up to 20% of cases.
- An Indeterminate finding means that even though an adequate number of cells was removed during the fine needle biopsy, examination with a microscope cannot reliably classify the result as benign or cancer.
- The biopsy may be indeterminate because the nodule is described as a Follicular Lesion.
- These nodules are cancerous 20-30% of the time.
- However, the diagnosis can only be made by surgery.
- The biopsy may also be indeterminate because the cells from the nodule have features that cannot be placed in one of the other diagnostic categories.
- This diagnosis is called atypia, or a follicular lesion of undetermined significance.
- Diagnoses in this category will contain cancer rarely, so repeat evaluation with FNA or surgical biopsy to remove half of the thyroid containing the nodule is usually recommended.
- The biopsy may also be nondiagnostic or inadequate.
- This result is obtained in less than 5% of cases when an ultrasound is used to guide the FNA.
- This result indicates that not enough cells were obtained to make a diagnosis but is a common result if the nodule is a cyst.
- These nodules may require re-evaluation with second fine needle biopsy, or may need to be removed surgically depending on the clinical judgment of your doctor.
- All thyroid nodules that are found to contain a thyroid cancer, or that are highly suspicious of containing a cancer, should be removed surgically.
- Most thyroid cancers are curable and rarely cause life-threatening problems (see Thyroid Cancer).
- Thyroid nodules that are benign by FNA or too small to biopsy should still be watched closely with ultrasound examination every 6 to 12 months and annual physical examination by your doctor.
- Surgery may still be recommended even for a nodule that is benign by FNA if it continues to grow, or develops worrisome features on ultrasound over the course of follow up.
Thyroid Cancer
Thyroid cancer is relatively uncommon compared to other cancers.
Thyroid cancer is usually very treatable and is often cured with surgery (see Thyroid Surgery) and, if indicated, radioactive iodine.
Even when thyroid cancer is more advanced, effective treatment is available for the most common forms of thyroid cancer.
Even though the diagnosis of cancer is terrifying, the prognosis for most patients with papillary and follicular thyroid cancer is usually excellent.
Papillary thyroid cancer.
- Papillary thyroid cancer is the most common type, making up about 70% to 80% of all thyroid cancers.
- Papillary thyroid cancer can occur at any age.
- It tends to grow slowly and often spreads to lymph nodes in the neck.
- However, unlike many other cancers, papillary cancer has a generally excellent outlook, even if there is spread to the lymph nodes.
Follicular thyroid cancer.
- Follicular thyroid cancer makes up about 10% to 15% of all thyroid cancers.
- Follicular cancer can spread to lymph nodes in the neck, but this is much less common than with papillary cancer.
- Follicular cancer is also more likely than papillary cancer to spread to distant organs, particularly the lungs and bones.
Medullary thyroid cancer.
- Medullary thyroid cancer (MTC), accounts for approximately 2% of all thyroid cancers.
- Approximately 25% of all MTC runs in families and is associated with other endocrine tumors.
- In family members of an affected person, a test for a genetic mutation can lead to an early diagnosis of medullary thyroid cancer and, as a result, to curative surgery.
Anaplastic thyroid cancer.
- Anaplastic thyroid cancer is the most advanced and aggressive thyroid cancer and the least likely to respond to treatment.
- Anaplastic thyroid cancer is very rare and is found in less than 2% of patients with thyroid cancer.
- Thyroid cancer often presents as a lump or nodule in the thyroid and usually does not cause any symptoms (see Thyroid Nodule).
- Occasionally, patients themselves find thyroid nodules by noticing a lump in their neck while looking in a mirror, buttoning their collar, or fastening a necklace.
- Some patients may complain of pain in the neck, jaw, or ear.
- If a nodule is large enough to compress the windpipe or oesophagus, it may cause difficulty with breathing, swallowing, or cause a “tickle in the throat”. Even less commonly, hoarseness can be caused if a thyroid cancer invades the nerve that controls the vocal cords.
The important points to remember are that cancers arising in thyroid nodules generally
- do not cause symptoms,
- thyroid function tests are typically normal even when cancer is present,
- and the best way to find a thyroid nodule is to make sure that your doctor examines your neck as part of your periodic check-up.
- A diagnosis of thyroid cancer can be suggested by the results of a fine needle aspiration biopsy of a thyroid nodule and can be definitively determined after a nodule is surgically excised (see Thyroid Nodules).
- Although thyroid nodules are very common, less than 1 in 10 will be a thyroid cancer.
Surgery.
- The primary therapy for all types of thyroid cancer is surgery (see Thyroid Surgery).
- The extent of surgery for thyroid cancers (removing only the lobe involved with the cancer- called a lobectomy or the entire thyroid – called a total thyroidectomy) will depend on the size of the tumour and on whether or not the tumour is confined to the thyroid.
Radioactive iodine therapy.
- (Also referred to as I-131 therapy). Thyroid cells and most differentiated thyroid cancers absorb and concentrate iodine. That is why radioactive iodine can be used to eliminate all remaining normal thyroid tissue and potentially destroy residual cancerous thyroid tissue after thyroidectomy.
- The procedure to eliminate residual thyroid tissue is called radioactive iodine ablation. This produces high concentrations of radioactive iodine in thyroid tissues, eventually causing the cells to die.
- Periodic follow-up examinations are essential for all patients with thyroid cancer because the thyroid cancer can return—sometimes several years after successful initial treatment.
- These follow-up visits include a careful history and physical examination, with particular attention to the neck area.
- Neck ultrasound is an important tool to view the neck and look for nodules, lumps or cancerous lymph nodes that might indicate the cancer has returned.
- Blood tests are also important for thyroid cancer patients. TSH and Thyroglobulin.
- In addition to routine blood tests, your doctor may want to repeat a whole-body iodine scan to determine if any thyroid cells remain.
- Overall, the prognosis of thyroid cancer is excellent, especially for patients younger than 45 years of age and those with small cancers.
- Patients with papillary thyroid cancer who have a primary tumor that is limited to the thyroid gland have an excellent outlook.
- Ten-year survival for such patients is 100% and death from thyroid cancer anytime thereafter is extremely rare.
- For patients older than 45 years of age, or those with larger or more aggressive tumours, the prognosis remains very good, but the risk of cancer recurrence is higher.
- The prognosis may not be quite as good in patients whose cancer is more advanced and cannot be completely removed with surgery or destroyed with radioactive iodine treatment.
- Nonetheless, these patients often are able to live a long time and feel well, despite the fact that they continue to live with cancer.
Thyroid Surgery
Your doctor may recommend that you consider thyroid surgery for 4 main reasons:
- You have a nodule that might be thyroid cancer.
- You have a diagnosis of thyroid cancer.
- You have a nodule or goiter that is causing local symptoms – compression of the trachea, difficulty swallowing or a visible or unsightly mass.
- You have a nodule or goiter that is causing symptoms due to the production and release of excess thyroid hormone – either a toxic nodule, a toxic multinodular goiter or Graves’ disease.
The extent of your thyroid surgery should be discussed by you and your Doctor and can generally be classified as a partial thyroidectomy or a total thyroidectomy.
A hemi-thyroidectomy or thyroid lobectomy
- where one lobe (one half) of the thyroid is removed;
An isthmusectomy
- removal of just the bridge of thyroid tissue between the two lobes; used specifically for small tumors that are located in the isthmus.
A total or near-total thyroidectomy
- is removal of all or most of the thyroid tissue.
In experienced hands, thyroid surgery is generally very safe.
Complications are uncommon, but the most serious possible risks of thyroid surgery include:
- bleeding in the hours right after surgery that could lead to acute respiratory distress;
- injury to a recurrent laryngeal nerve that can cause temporary or permanent hoarseness, and possibly even acute respiratory distress in the very rare event that both nerves are injured;
- damage to the parathyroid glands that control calcium levels in the blood, leading to temporary, or more rarely, permanent hypoparathyroidism and hypocalcaemia.
These complications occur more frequently in:
- patients with invasive tumours or extensive lymph node involvement,
- in patients undergoing a second thyroid surgery,
- and in patients with large goiters that go below the collarbone into the top of the chest (substernal goiter).
Overall the risk of any serious complication should be less than 2%.
- For patients with papillary or follicular thyroid cancer, many, but not all, surgeons recommend total or near-total thyroidectomy when they believe that subsequent treatment with radioactive iodine might be necessary.
- For patients with larger (>1.5 cm) or more invasive cancers and for patients with medullary thyroid cancer, local lymph node dissection may be necessary to remove possibly involved lymph node metastases.
- A hemithyroidectomy may be recommended for overactive solitary nodules or for benign one-sided nodules that are causing local symptoms such as compression, hoarseness, shortness of breath or difficulty swallowing.
- A total or near – total thyroidectomy may be recommended for patients with Graves’ Disease (see Hyperthyroidism) or for patients with large multinodular goiters.
- The answer to this depends on how much of the thyroid gland is removed.
- If half (hemi) thyroidectomy is performed, there is an 80% chance you will not require a thyroid pill UNLESS you are already on thyroid medication for low thyroid hormone levels (e.g. Hashimoto’s thyroiditis) or have evidence that your thyroid function is on the lower side in your thyroid blood tests.
- If you have your entire gland removed (total thyroidectomy) then you have no internal source of thyroid hormone remaining and you will definitely need lifelong thyroid hormone replacement.