Anaplastic Thyroid Cancer Long-Term Follow-Up: Why Do I Need It?
You may have heard or experienced one of the following:
- Anaplastic Thyroid Cancer is one of the worst cancers
- You didn't know you had thyroid anaplastic thyroid cancer until after your thyroid surgery.
- Your anaplastic thyroid cancer was not completely removed (this is called persistent anaplastic thyroid cancer).
- Your anaplastic thyroid cancer has come back! (this is called recurrent anaplastic thyroid cancer).
- Your anaplastic thyroid cancer is located in other sites of your body other than your neck (this is distant spread of your cancer or distant metastases)
- You had an anaplastic thyroid cancer and you underwent removal of half of your thyroid gland -called a thyroid lobectomy.
- You had a anaplastic thyroid cancer and underwent removal of all of your thyroid gland-called a total thyroidectomy.
If you had an anaplastic thyroid cancer and completed all of your treatment(s), life-long follow-up is strongly encouraged among all experts in thyroid cancer for three reasons:
- To make sure that your thyroid hormone levels in your blood are at the right level for you! It is possible you may not require any thyroid hormone pill or supplement, however most anaplastic thyroid cancer patients during follow-up are maintained on thyroid hormone pills. There are several different types of thyroid hormone pills and you should discuss this with your endocrinologist to make sure that you are feeling well and your hormone levels are right for you. Your thyroid hormone should not be too low or too high for your specific needs. The amount of thyroid hormone that you may need may change throughout your lifetime due to many reasons including age, body weight, pregnancy, and more.
- To determine whether all of your anaplastic thyroid cancer was completely removed. If anaplastic thyroid cancer is still evident in your neck following your initial surgery, this is called persistent anaplastic thyroid cancer. Unfortunately, this is more common due to two important factors. First, inexperienced surgeons are not prepared for the surgery and uncomfortable and do not have the experience or skill set to complete the necessary surgery. Second, the anaplastic thyroid cancer patient is not a valid surgical candidate but the inexperience thyroid cancer surgeon is unable to determine this prior to surgery. Persistent anaplastic thyroid cancer may be preventable in many patients but is not a reversible or correctable event following a poorly conceived surgery. We have written a complete section on persistent anaplastic thyroid cancer just for you so you can understand this issue and how best to approach it. Most importantly, don't let it happen to you
- To determine whether your anaplastic thyroid cancer has come back. If your anaplastic thyroid cancer has been gone for a period of time and comes back, this is called recurrent anaplastic thyroid cancer. We have written a complete section on recurrent anaplastic thyroid cancer just for you. Important questions that need to be asked:
- Where has the recurrent anaplastic thyroid cancer been found?
- What treatment (s) have you had for your anaplastic thyroid cancer?
- What is the genetic appearance of your anaplastic thyroid cancer?
Recurrent and metastatic is not curable. We have written an entire section on anaplastic thyroid cancer treatments. If your anaplastic thyroid cancer has recurred, you should be evaluated and treated in a center that specializes in new personalized therapies directed at this most lethal cancer.
Anaplastic Thyroid Cancer Patient Follow-Up:Who Should Do It?
The anaplastic thyroid cancer patient follow-up can be performed by surgeons, endocrinologist, oncologists and others. But what is most important is that those individuals which are following the anaplastic thyroid cancer patient are truly experts in the management, evaluation, and treatment of the disease. The Clayman Thyroid Cancer Center believes that the anaplastic thyroid cancer patient follow-up is best managed by an endocrinologist with defined expertise in the evaluation, management, and follow-up of anaplastic thyroid cancer patients. Communication between the interdisciplinary team of endocrinologists, surgeons, radiologists, and other members of the anaplastic thyroid cancer team is critical. This is the absolute foundation of the Clayman Thyroid Cancer Center approach.
Anaplastic thyroid cancer Follow-Up: What Factors Influence How Often and What Studies Should Be Obtained?
Anaplastic thyroid cancer patients who have completed treatments, the timing of follow-up appointments and the types of studies obtained in the follow up of their anaplastic thyroid cancer depends upon:
- 1. The anaplastic thyroid cancer treatment(s) the patient received.
- 2) The location(s) the anaplastic thyroid cancer was found in the body.
- a. Thyroid gland only
- b. The soft tissues of the neck
- c. The neck lymph nodes (rare)
- d. Sites outside of the neck (distant spread of the anaplastic thyroid cancer).
- 3) Whether the anaplastic thyroid cancer patient was ever considered free of disease.
- 4) The anaplastic thyroid cancer pathology (What was found when looking under the microscope at the anaplastic thyroid cancer surgery specimen)? We have written a whole section on this for you to better understand your anaplastic thyroid cancer. This is called Anaplastic Thyroid Cancer Staging (TNM staging)
- a. Did the anaplastic thyroid cancer grow out of the confines of the thyroid gland itself?
- i. If it did grow out, what did it grow into?
- 1. The muscle which lays over the thyroid gland?
- 2. The breathing tube (trachea)
- 3. The swallowing tube (esophagus)
- b. Did the anaplastic thyroid cancer grow into blood vessels or lymphatic vessels?
- c. Did the anaplastic thyroid cancer grow into nerves or other nearby structures?
- d. Did the anaplastic thyroid cancer spread into neck lymph nodes?
- i. The lymph nodes along the breathing tube or swallowing tube- called the central compartment lymph nodes?
- ii. The lymph nodes on the side of the neck- called the lateral neck?
- iii. The soft tissues of the neck outside of any lymph nodes?
- e. Did the anaplastic thyroid cancer spread to other areas of the body outside of the neck? Meaning is there distant spread of the cancer?
- i. Lungs
- ii. Bone
- iii. Liver
- iv. Other sites
Anaplastic Thyroid Cancer Follow-Up: How Frequent and What Studies Should Be Obtained?
Follow-up of anaplastic thyroid cancer patients is not uniformly agreed upon. In most cases , it is usually accomplished by an endocrinologist every three to four months for the first two years, twice annually for two years and then annually thereafter, if there is no evidence of disease.
Every anaplastic thyroid cancer patient should have the following examinations included in generally every follow-up appointment:
- physical examination: This will include examination of the neck and thyroid bed and examination of the voice box if there is concern over changes in voice or swallowing
- Ultrasound of the neck (see ultrasound of the neck for anaplastic thyroid cancer)
- Blood tests for :
- 1) Free T4 level
This is the blood level of the major hormone normally produced by the thyroid gland. It is also a direct measurement of the most commonly prescribed thyroid hormone pill, levothyroxine. The dose of thyroid hormone pill will be based upon the blood thyroid stimulating hormone (TSH) level described below.
- 2) TSH (Thyroid Stimulating Hormone)
The potential risk of your anaplastic thyroid cancer coming back or spreading will determine the amount of thyroid hormone that will be prescribed to you in the replacement of your thyroid hormone. The American Thyroid Association has guidelines for the blood level of TSH which should be sought based upon the risk of the anaplastic thyroid cancer recurring. That risk may be low, intermediate or high risk and each is associated with a different range of TSH blood levels.
All anaplastic thyroid cancer patients are considered high risk patients. For high-risk patients, the thyroid hormone dose will be high enough to suppress the thyroid stimulating hormone (TSH) below the range that is normal for someone not diagnosed with anaplastic thyroid cancer. The goal is to prevent the growth of anaplastic thyroid cancer cells while providing essential thyroid hormone to the body. At first, TSH levels will probably be suppressed to below 0.1 mU/L. The level may later change to 0.1 to 0.5, depending on your body's response to the treatment and time.
- 3) Thyroglobulin
Thyroglobulin is a protein produced by thyroid cells (both papillary, follicular , and hurthle cell thyroid cancers as well as normal cells) that can be measured in your blood. After removal of the entire thyroid gland, thyroglobulin can be used as a "cancer marker." Its number should be as low as possible. Sometimes this is termed "undetectable." After your surgery with or without radioactive iodine, it may take months or even years for the thyroglobulin number to come down to zero or undetectable.
Generally speaking, most anaplastic thyroid cancers produce little to no detectable thyroglobulin. So for most anaplastic thyroid cancer patients, thyroglobulin is an ineffective blood monitoring approach for the cancer. Depending on the level of thyroglobulin in your blood, your doctor may want to monitor you more closely with other tests or scans and/or prescribe additional treatment.
If you had a thyroid lobectomy rather than a total thyroidectomy, your remaining thyroid lobe will almost always produce some amount of Thyroglobulin. However, it may still be helpful to follow your Thyroglobulin levels over time. If significant changes in Thyroglobulin levels occur over time, your doctor may recommend further imaging studies to locate the source.
Editors Note: Not only do anaplastic thyroid cancers rarely produce thyroglobulin, even the poorly differentiated thyroid cancers (which can often be very difficult to distinguish from anaplastic thyroid cancers) may similarly produce little to no thyroglobulin blood levels. It still may be reasonable to continue to monitor thyroglobulin in patients with anaplastic thyroid cancer just in case recurrent disease occurs that differs in its ability to produce thyroglobulin (although this is unlikely to occur).
- 4) Thyroglobulin antibody
Some people produce a very large protein that for some reason recognizes the normal thyroglobulin protein as being "abnormal". These very large proteins are called anti-thyroglobulin antibodies. These are not harmful but are a sign of an autoimmune disease where the body recognizes itself as being abnormal. The presence of Thyroglobulin antibodies makes Thyroglobulin a largely useless (insensitive) blood test for monitoring anaplastic thyroid cancer. Whenever thyroglobulin is being measured, thyroglobulin antibodies must also be measured as well.
Anaplastic thyroid cancer patients are at high risk of recurring for years following their initial treatment: What Additional Studies Are Indicated at Every Follow-up?
CT scanning of the neck and or chest
CT scanning of the neck is obtained for all anaplastic thyroid cancer patients when there have been surgical or pathology findings of the anaplastic thyroid cancer which suggest a high risk of recurrence in locations that ultrasound has limitations. This includes the voice box (larynx), trachea (breathing tube) and esophagus as well as deeper structures in the neck and below the collar bones or chest wall. CT scan of the neck should be obtained with contrast otherwise its use is extremely limited.
In all anaplastic thyroid cancer patients, a baseline CT scan of the chest should routinely be obtained and periodically re-examined with every subsequent follow-up visit. The baseline CT scan of the chest is used for comparison for every anaplastic thyroid cancer patient
A PET scan is a special imaging study using a specially designed sugar that "lights up" on nuclear imaging and when combined with a CT scan is called a PET/CT scan. PET/CT scan is expectantly useful for all anaplastic thyroid cancer follow-up appointments. It is a quite effective complete analysis of most distant sites at risk of spread of anaplastic thyroid cancer with the exception of the brain and spinal cord itself.
MRI scanning is particularly beneficial for examination of the brain, spinal column, or bones when there has been a history or concern for involvement of anaplastic thyroid cancer in those sites. This study does not produce any radiation effect and is given with an intravenous contrast agent called gadolinium.
Radioactive Iodine (RAI) Whole Body Scanning
RAI scanning is rarely of any use or benefit to patients with anaplastic thyroid cancer. In the rare circumstance that an anaplastic thyroid cancer has distant spread of disease and is producing thyroglobulin, RAI may be considered by some. In my opinion, this should not be the case and such anaplastic thyroid cancer patients should consider new personalized therapy approaches since time is of the essence. See what we have written about anaplastic thyroid cancer treatments.