Medullary Thyroid Cancer Diagnosis

Following genetic counseling, once a diagnosis of inherited medullary thyroid cancer is diagnosed in a family, other family members may seek analysis of their blood cells to determine whether they similarly carry the mutation of the gene of their family member. The risk of passing the genetic mutation of the RET gene to subsequent generations is 50%. Specific RET mutations produce different outcomes. For example, some mutations are know to produce medullary thyroid cancers very early in life and others may not produce cancers until much later years. Similarly, some RET mutations are know to produce very aggressive medullary thyroid cancers that may spread to neck lymph nodes in life very early and distant spread to other sites in the body. In these genetic cases of medullary thyroid cancer, thyroid surgery may need to be performed on infants and very young children. Only the most experience thyroid cancer surgeons should every perform these operations.

It is generally recommended that all patients with medullary thyroid cancer be screened for pheochromocytoma (adrenal gland tumors which have the potential to overproduce flight or fight type hormones) prior to surgery since genetic screening results often may not be available until after an operation is planned. These tumors may greatly increase the risk of a serious operation cardiac event if not know prior to the medullary thyroid cancer surgery.

Those individuals whom are found to be genetic carriers of the familial ret mutation, should be evaluated by a medullary thyroid cancer team that is familiar with all aspects of the inherited diseases. There is now much known and further knowledge is being established regarding the specific RET mutations and how they affect the medullary thyroid cancer patient.

Ret Mutations Predict

• invasion outside of the thyroid
• spread to lymph nodes
• risk of spread to distant sites
• age of onset
• mortality

• MEN 2A
  • Medullary thyroid cancer
  • Parathyroid tumors (high calcium and parathyroid hormone levels)
  • Pheochromocytoma tumors (adrenal gland tumor that may produce very high adrenaline like hormones)
• MEN2B
  • Medullary thyroid cancer
  • Pheochromocytoma tumors
  • Mucosal ganglioneuromas
  • Marfanoid habitus (tall stature with long arms)
  • Parathyroid tumors are rarely found
• Hereditary non-MEN Medullary Thyroid Cancer

Medullary thyroid cancers may also produce symptoms of diarrhea. The diarrhea of medullary thyroid cancer is caused by increased gastrointestinal secretions and hypermotility due to the hormones secreted by the medullary thyroid cancer (calcitonin, serotonin, prostaglandins or VIP). Screening and surgical intervention of inherited ret mutation carriers may begin as early as infancy (for example in MEN2B) or later in life based upon the specific RET mutations and the anticipated age of onset of medullary thyroid cancer. Screening of ret mutation family members includes blood calcitonin and CEA levels as well as high resolution neck ultrasound.

If you have been diagnosed with a medullary thyroid cancer, your most important task is to identify an expert in medullary thyroid cancer surgery. This is the most important step! Medullary thyroid cancer in the neck is a surgical disease!!! Medullary thyroid cancer in the neck is cured and controlled with surgery!! Many thyroid surgeons rarely if ever see or operate on medullary thyroid cancers. Occasional thyroid surgeons may have never seen a medullary thyroid cancer. Infants and children who possess ret mutations should only be managed by the most experienced medullary thyroid cancer surgeons!

The following are a list of tests that are frequently used in patients with a diagnosis of medullary thyroid cancer

• Complete Medical History and Physical Examination
• Laryngoscopy (looking at the voice box)
• Genetic counseling
• Genetic testing for inherited mutation of ret gene
• Blood Laboratory studies
  • TSH
  • Free T4
  • Calcitonin
  • CEA
  • Serum metanephrines
  • PTH
  • Ca

• Ultrasound of Neck with FNA (fine needle aspiration of any suspicious lateral neck lymph nodes)
• CT Scan Neck
• CT Scan Chest
• CT Scan Abdomen and Pelvis

• MRI scan as indicated primarily for concern of spine or soft tissue spread
• PET/CT scan as indicated for assessment of metastatic disease (note medullary thyroid cancers may not be “hot” on PET scanning)

Medical history and physical examination is required for all patients with a potential diagnosis of medullary thyroid cancer

If there is a suspicion that you may have a diagnosis of medullary thyroid cancer, 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 medullary thyroid cancer, sudden cardiac death, high blood calcium levels, kidney stones, adrenal tumors, parathyroid tumors... these are all important factors.

Your doctor will examine you to get more information about possible signs of medullary 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. They will look at you eyes and in your mouth as well. Examination of your voice box is part of the physical examination obtained by the surgeon for any thyroid lump. This is called a laryngoscopy and more is written about it at the end of this section.

The Diagnosis of Medullary Thyroid Cancer is Made by Fine Needle Aspiration (FNA) Biopsy

• The diagnosis of medullary thyroid cancer is made with an ultrasound guided small sampling of cells from the thyroid gland or neck lymph nodes (or both in some instances).
• Ultrasound is used to see the thyroid or the lymph node(s) during the biopsy, which helps make sure they are getting FNA samples from the right areas.
• FNA is generally done on all thyroid nodules that are big enough to be felt. This means that they are larger than about 1 centimeter (about 1/2 inch) across.
• FNA biopsies of swollen or abnormal appearing lymph nodes in the neck may be more informative than the thyroid nodule itself in obtaining a diagnosis of medullary thyroid cancer.
• Cells from the suspicious area are removed without an incision or discomfort and looked at under a microscope.
• The process of obtaining this small sampling of cells is called fine needle aspiration (FNA) cytology.
  • This type of biopsy can usually be done in your doctor’s office or clinic.
  • Before the biopsy, local anesthesia (numbing medicine) may be injected into the skin over the thyroid nodule.
  • Your doctor will place a thin, hollow needle directly into the nodule to aspirate (take out) some cells and possibly a few drops of fluid into a syringe.
  • The doctor usually repeats this 2 or 3 more times, taking samples from several areas of the nodule.
  • The content of the needle and syringe are then placed on a glass slide and then the FNA samples are then sent to a lab, where they are looked at under a microscope by the expert Cytologist to see if the cells look cancerous or benign.
• Cytology means looking at just the cells under the microscope.
• Thyroid cytology requires an expert physician (called a Cytologist) trained specifically in the diagnosis of medullary thyroid cancer!!!
• Bleeding at the biopsy site is very rare except in people with bleeding disorders. Even when this occurs, the bleeding is almost always very self limited. Be sure to tell your doctor if you have problems with bleeding or are taking medicines that could affect bleeding, such as aspirin or blood thinners.
• Sometimes an FNA biopsy will need to be repeated because the samples didn’t contain enough cells.
• FNA biopsies can be analyzed either with a special staining of the cells for calcitonin protein or even analyzed similar to a blood sample for calcitonin levels. Both of these approaches can also be used to diagnose medullary thyroid cancer.
• Rarely, the FNA biopsy may come back as benign even though a diagnosis of medullary thyroid cancer is actually present.

This is an example of a cytology slide of a medullary thyroid cancer. Medullary thyroid cancers are a type of neuroendocrine cancer. These small “blue cells” are actually the center of the medullary thyroid cancer cells called the nucleus. The light blue hazy material in the slide is called amyloid. These two findings together produce a diagnosis of medullary thyroid cancer. Special analysis of calcitonin within these cells can also be obtained to further support the diagnosis of medullary thyroid cancer.

This is a pathology slide showing medullary thyroid cancer cells which have been stained with this red marker for calcitonin. Calcitonin is not present in the center of the cell which is called the nucleus. This special staining is basically only seen in the medullary thyroid cancer cells and provides a definitive diagnosis of medullary thyroid cancer.

Diagnosis of Medullary Thyroid Cancer: What If The Diagnosis is Not Clear?

Sometimes FNA results come back as a malignancy or suspicious for malignancy of a “small cell type”. This diagnosis is not likely from a skilled thyroid pathologist. If this happens, the doctor may request the pathologist to do special stains on the cytology such as calcitonin. Additionally, your doctor may request that you get a blood sample and test for both calcitonin and CEA levels. For medullary thyroid cancer, this is critical information. The preferred minimal surgical operation is to remove the entire thyroid gland and the lymph nodes of the central compartment. The operation only takes about one hour in skilled hands but should only be performed by the most skilled thyroid cancer surgeons. Incomplete or complications in this surgery are too common with infrequent thyroid surgeons. Inexperienced surgeons performing medullary thyroid cancer surgery may complicate the ability to ultimately control the medullary thyroid cancer itself and risk long term injury to the nerves of the voice box and glands that control calcium in the body.

If for some reason the diagnosis of medullary thyroid cancer is not clear after an FNA biopsy, you might need a more involved biopsy to get a better microscopic examination of the nodule or thyroid mass. In particular, if the doctor has reason to think the nodule is suspicious for a diagnosis of medullary thyroid cancer based upon the nodule size, symptoms, blood calcitonin levels or ultrasound appearance, the preferred biopsy is a thyroid lobectomy (removal of the half of the thyroid gland that possesses the nodule). Thyroid lobectomies are done in an operating room while you are under general anesthesia (in a deep sleep). The thyroid lobectomy can then be examined while the patient is asleep in the operating room by the pathologist who specializes at looking at surgical specimens that are rapidly frozen in liquid nitrogen, stained, then examined under a microscope. Although special stains for calcitonin cannot be done at that time, the diagnosis of malignancy and the small cells suspicious for medullary thyroid cancer can be obtained while the patient is asleep and the appropriate surgery of removal of all of the thyroid gland (total thyroidectomy) and central compartment dissection completed ...without the patient requiring a second operation!!! Make sure you have an expert medullary thyroid cancer team. This includes your surgeon, pathologist, endocrinologist and oncologist, radiologist, and genetic counselor…just to name a few of the team!

Imaging tests for a Diagnosis of Medullary Thyroid Cancer

Imaging tests may be done for a number of reasons, including to help find suspicious areas that might be cancer, to learn how far cancer may have spread, and to help determine the extent of surgery and the role of other treatments or therapies.

People who have or may have a diagnosis of medullary thyroid cancer will get one or more of the following tests:

Ultrasound

Ultrasound uses sound waves to create pictures inside your neck. The thyroid ultrasound must not only examine the thyroid gland but also must include a comprehensive examination of your neck lymph nodes. For this test, a small, wand-like instrument called a transducer is placed on the skin in front of your thyroid gland and all levels of the neck. It gives off sound waves and picks up the echoes as they bounce off the thyroid (and other underlying neck structures). The echoes are converted by a computer into a black and white image on a computer screen. You are not exposed to any radiation during this test.

This test can help determine if a thyroid nodule is solid or filled with fluid. (Solid nodules are more likely to be cancerous.) It can also be used to check the number and size of thyroid nodules. Further, it can even reveal what the blood supply looks like to these nodules. How a nodule looks on ultrasound can sometimes suggest if it is likely to be a cancer, but ultrasound can’t tell for sure. Importantly, a cystic nodule is most commonly benign (not cancer). However, a cystic lymph node in the bottom half of the neck is most commonly a diagnosis of papillary thyroid cancer.

Ultrasound of the thyroid gland. The yellow arrow points to the breathing tube (trachea). The green arrow points to a nodule in the left side of the thyroid gland (the ultrasound pictures are a mirror image: meaning left side of image is on the patient’s right side and vice versa) which is a FNA biopsy proven diagnosis of medullary thyroid cancer.

For thyroid nodules, ultrasound is used to guide a biopsy needle into the thyroid nodule to obtain a confident sampling of the cells within it.

Expert ultrasound can also help confirm a diagnosis of medullary thyroid cancer which has spread to the lymph nodes of the neck. The expert ultrasonographer will look for multiple changes. Although many unskilled observers would believe that size is a major issue, but in fact it is not. High resolution ultrasound can detect a diagnosis of medullary thyroid cancer spread to lymph nodes as small as 1-2 mm (the size of a tip of a ball point pen). When looking at the lymph nodes in the neck with ultrasound, the following are important criteria which may lead to a FNA needle biopsy to confirm disease.

• Full of rounded lymph nodes
• Displacement or disruption of the normal ultrasonic “architecture” of a lymph node
• Microcalcifications within lymph nodes (small ultrasonic calcifications)
• Disorganized vascular flow to the lymph node
• Larger or asymmetric lymph nodes when comparing one side of the neck to the other
• Location, location, location-the diagnosis of medullary thyroid cancer spread to neck lymph nodes is quite predictable.
• Editorial note: One weakness of ultrasound is that it cannot distinguish cancerous from inflammatory lymph nodes. Both can have very similar appearances however ultrasound guided FNA will provide the necessary microscopic ability to confirm or rule out a diagnosis of medullary thyroid cancer.
• Calcitonin can be analyzed in the FNA of a suspicious lymph node to confirm the diagnosis of metastatic medullary thyroid cancer to a lymph node. (Editorial note: Calcitonin is not produced in normal lymph nodes. Therefore, if a lymph node does not contain medullary thyroid cancer in a patient, the calcitonin level of the lymph node would be a similar level as the medullary thyroid cancer patient’s blood level. A very high level of calcitonin in a lymph node is the same as a medullary thyroid cancer positive cytology.)

We perform an ultrasound on all of our patients ourselves because we have learned that ultrasounds performed elsewhere are not as accurate as we need. The most highly skilled ultrasound will detect abnormalities within lymph nodes within 2 mm. This is approximately the size of a ball point pen head. Your ultrasound should be performed by someone who is specifically dedicated to the ultrasound examination of the thyroid and neck.

The ultrasound study will critically look not only at the thyroid but all the tissues in your neck.  The ultrasound can show whether something is cystic or solid.  It can see the blood supply to a particular area.  It can reveal microscopic calcifications that may indicate a cancer. Ultimately, your ultrasound will determine whether a biopsy with a tiny needle is indicated or whether simple blood test may only be indicated.  Even if you have already had a biopsy, another biopsy may be indicated if:

• The first biopsy did not provide a diagnosis
• The ultrasound shows something that was previously not seen.

If ultrasound with needle biopsy detects that medullary thyroid cancer has spread to neck lymph nodes, other x-rays are indicated.

Ultrasound of the neck lymph nodes. The red arrow points to the carotid artery. The green box displays a 1.5 cm lymph node with the red and blue colors demonstrating disorganized blood flow. The FNA confirms a diagnosis of medullary thyroid cancer spread (metastatic) to a lymph node.

Computed tomography (CT) scan for Medullary Thyroid Cancer

The CT scan of the neck for medullary thyroid cancer is an x-ray test that produces detailed cross-sectional images of your body from the bottom of your brain to the middle of your chest. It can help determine the location and size of the medullary thyroid cancer, whether the cancer has invaded into any nearby structures, and whether they have spread to lymph nodes in nearby areas. A CT scan can also be used to look for spread into distant organs such as the lungs.

A CT scanner has been described as a large donut, with a narrow table in the middle opening. You will need to lie still on the table while the scan is being done. CT scans take longer than regular x-rays, and you might feel a bit confined by the ring while the pictures are being taken.

Instead of taking one picture, like a regular x-ray, a CT scanner takes many pictures while you lie on the table. A computer then combines these pictures into images of slices of the part of your body being studied. A CT scan designed for a diagnosis of papillary thyroid cancer is sliced at 1mm steps. It is an incredibly detailed study that creates very exquisite images.

Before the test, you will be asked to receive an IV (intravenous) line through which a contrast dye is delivered. This helps better outline structures in your body. The injection may cause some flushing (a feeling of warmth, especially in the face). Some people are allergic and get hives. Rarely, more serious reactions like trouble breathing or low blood pressure can occur. Be sure to tell the doctor if you have any allergies or have ever had a reaction to any contrast material used for x-rays.

This is a CT scan of the neck in a patient with a small medullary thyroid cancer of the right thyroid lobe. The dashed arrow points to a small lymph node in the right mid neck. (CT scan images are mirror imaged, meaning the left side of the xray represents the right side of the patient.)

The CT scan for a diagnosis of medullary thyroid cancer provides different information to your doctor than the ultrasound. The ultrasound tells the doctor if there is something abnormal. The CT scan tells the doctor where the abnormality is located! Both studies complement each other. The CT scan of the neck also can look at areas of the neck that the ultrasound cannot study because sounds waves cannot pass effectively through bone, cartilage or air. Specifically, the CT scan can effectively see behind the jaw bone (mandible), collar bone (clavicle) or chest wall and also behind the voice box (larynx), breathing tube (trachea), and swallowing tube (esophagus). In all of these sites, the ultrasound examination can be quite limited and therefore a CT scan may provide valuable additional information regarding where the papillary thyroid cancer is and where it is not. Ultimately, all of these studies will determine the extent of required surgery. In patients with a diagnosis of medullary thyroid cancer, a CT scan of the neck is obtained in every patient! In fact, a CT scan of the neck, chest and abdomen and pelvis is obtained in every patient with a diagnosis of medullary thyroid cancer.

The CT scan of the chest provides an excellent baseline examination (for following) of the lungs and the lymph nodes of the chest, both of these sites the highest risk of distant spread in patients with a diagnosis of medullary thyroid cancer.

The CT scan of the abdomen and pelvis provides an excellent examination of the liver and abdominal lymph nodes and also provides a screening tool for the adrenal gland for potential tumors in patients with a diagnosis of medullary thyroid cancer which may also be the hereditary type until proven otherwise.

Magnetic resonance imaging (MRI) scan

Like CT scans, MRI scans can be used to look for a diagnosis of medullary thyroid cancer in the thyroid, or cancer that has spread to nearby or distant parts of the body. But ultrasound is usually the first choice for looking at the thyroid and neck structures. MRI scans are particularly helpful in looking at the brain and spinal cord.

MRI scans use radio waves and strong magnets instead of x-rays, therefore there is no radiation exposure. The energy from the radio waves is absorbed and then released in a pattern formed by the type of body tissue and by certain diseases. A computer translates the pattern into a very detailed image of parts of the body. A contrast material called gadolinium is often injected into a vein before the scan to better show details.

MRI scans take longer than CT scans – often up to an hour. You may have to lie inside a narrow tube, which can upset people with a fear of enclosed spaces. Newer, more open MRI machines can sometimes be used instead. The machine also makes buzzing and clicking noises, so some centers provide earplugs to block this noise out.

MRI scans are very sensitive to movement and moving during the scanning process produces artifacts that make interpretation difficult. Because people are constantly swallowing and unconsciously moving their voice box and swallowing structures (and therefore their thyroid gland and surrounding lymph nodes, CT of the neck is the preferred cross sectional study of the neck in patients with a diagnosis of medullary thyroid cancer.

Positron emission tomography (PET)/CT scan

For a PET scan, a radioactive substance (usually a type of sugar related to glucose, known as FDG) is injected into the blood. The amount of radioactivity used is very low. Because cancer cells in the body generally utilize sugar as their energy source to grow, they absorb more of the sugar than normal cells. After waiting about an hour, you lie on a table in the PET scanner for about 30 minutes while a special camera creates a picture of areas of radioactivity in the body.

This test can be very useful if you have a diagnosis of medullary thyroid cancer that has:

• Come back (recurred) following one or more surgeries
• Diagnosis of medullary thyroid cancer that has spread to other sites in the body

The PET/CT scan for a diagnosis of medullary thyroid cancer combines images of both a PET and CT scan at the same time. PET images alone are not very detailed. The computer shows the relative amount of radioactivity to a particular area and where the sugar is localized and it appears red or “hot”. The combination of these two images lets the doctor compare an abnormal area on the PET scan with its detailed appearance and location on the CT scan.

Insert PET/CT scan of recurrent medullary thyroid cancer

A PET/CT scan may be able to tell whether you have a diagnosis of medullary thyroid cancer which has spread to other sites of the body. Unfortunately, not all medullary thyroid cancers “light up” with PET imaging. There is no manner currently available to predict whether a PET/CT scan will be a useful imaging study in a diagnosis of medullary thyroid cancer in a particular patient until it is utilized. If a medullary thyroid cancer is shown to not be visualized on PET/CT imaging, further imaging with this x-ray is generally not considered.

Indications for obtaining a PET/CT scan for patient with a diagnosis of medullary thyroid cancer includes:

• Medullary thyroid cancer patient with extensive invasion outside of the thyroid gland itself
• A medullary thyroid cancer patient with extensive lymph node spread in the neck
• Recurrent Diagnosis of Medullary Thyroid Cancer (Cancers that have “come back” or recurred following one or more previous surgeries)
• A Diagnosis of Medullary Thyroid Cancer which has spread to sites outside of the neck (distant spread)
• A Diagnosis of Medullary Thyroid Cancer where the patient has a blood calcitonin or CEA level higher than anticipated for the disease that has been found

Blood tests

Blood tests alone cannot tell the extent of a diagnosis of medullary thyroid cancer. Blood tests are a tool used with other studies, to monitor the adequacy of your thyroid hormone levels produced by your thyroid or by the intake of prescription thyroid hormones.

Unlike papillary and follicular thyroid cancers which originate from thyroid producing cells called follicular cells. The cells that originate the medullary thyroid cancer are called parfollicular cells or C-cells.

Medullary thyroid cancers (and all C-cells for that matter) produce a totally different hormone in the body called calcitonin (or thyrocalcitonin). This hormone has no role in controlling metabolism of the body as does thyroid hormone.

Measurement of calcitonin in the blood of a patient with a diagnosis of medullary thyroid cancer, following surgery, can be used to determine whether the medullary thyroid cancer is still present in the body and still growing. It can be a very effective and minimally invasive monitoring tool in medullary thyroid cancer patients.

Quick Facts

Calcitonin lasts a long time in the body after the medullary thyroid cancer is removed because the hormone lasts very long in the blood. Calcitonin should not be measured in patients with a diagnosis of medullary thyroid cancer until at least three months following their definitive surgery. If the blood test for calcitonin is not low, there are only three possible explanations:

• There are still medullary thyroid cancer cells in the body
• There remains more thyroid tissue (likely in the upper portion of the thyroid gland) which is producing calcitonin that has not been removed.

Importantly, in patients with a diagnosis of medullary thyroid cancer who have undergone total thyroidectomy and neck dissection, if the calcitonin (or CEA) level rises again after being low, it is a sign that the cancer has almost certainly recurred.

This CEA (carcinoembryonic antigen) is another important blood test in the diagnosis of medullary thyroid cancer. This protein is normally found in the tissues of a developing human fetus and lost or minimally detectable in most individuals. Most patients with a diagnosis of medullary thyroid cancer produce significant detectable amounts of CEA in their blood. In fact, some medullary thyroid cancer experts look particularly at the ratio of calcitonin production to CEA and suggest that when the CEA is significantly rising compared to the calcitonin levels, the medullary thyroid cancer may be developing more worrisome aggressive potential. CEA is not specific for the diagnosis of medullary thyroid cancer and may be produced by other malignancies

Thyroid-stimulating hormone (TSH)

These are the main hormones made by the thyroid gland. Levels of these hormones may also be measured to get a sense of overall thyroid gland function. The T3 and T4 levels are usually normal in patients with a previously untreated diagnosis of medullary thyroid cancer. Medullary thyroid cancer does not produce either T3 or T4 hormones. Interesting, even in patients with a diagnosis of medullary thyroid cancers that are quite massive with very little normal appearing thyroid tissue, hypothyroidism is quite infrequent as well.

Other blood tests

You might have other blood tests as well. For example, if you are scheduled for medullary thyroid surgery, tests will be done to check your blood cell counts, to look for bleeding disorders, and to check the function of your liver and kidneys.

Other Tests

Vocal cord exam (laryngoscopy)

Thyroid tumors can sometimes affect the function of your voice box. Even if your voice sounds normal to you and others, this does not mean that your vocal cords are functioning normally. If you are going to undergo a surgery for a diagnosis of medullary thyroid cancer, a procedure called a laryngoscopy will probably be done first to see if the vocal cords are moving normally. For this exam, the doctor looks through the nose or down the throat at the larynx (voice box) with a special thin tube with a light and a lens on the end for looking at the voice box. This special tiny scope is inserted through the nose and there is little to no discomfort associated with the examination.

We have several pages on medullary thyroid cancer surgery, and one specifically on neck dissection for medullary thyroid cancer. If you have recently undergone a thyroid needle biopsy with a diagnosis of medullary thyroid cancer or have undergone a needle biopsy of a lymph node with a diagnosis of medullary thyroid cancer, these pages are for you.

The Diagnosis of Medullary Thyroid Cancer Can Be Associated with Predictable Behavior

• How the diagnosis of medullary thyroid cancer will behave is directly related to the size of the thyroid cancer within the gland itself.
• The diagnosis of papillary thyroid cancers that are less than 1.5 cm in size (less than ½ inch) have the best cure rates.
• The diagnosis of medullary thyroid cancer which is confined to the thyroid gland (no lymph node spread) is associated with a nearly 90% cure rate. The cure rates are less than that for papillary or follicular thyroid cancers, but still favorable.
• Most diagnosis of medullary thyroid cancer are not the hereditary form (75%) and predominated by women 3:2.
• The hereditary form of diagnosis of medullary thyroid cancer may be a preventable malignancy in some individuals undergoing total thyroidectomy.
• The diagnosis of hereditary form of medullary thyroid cancer be made by genetically analyzing the ret gene in at “risk” family members.
• The diagnosis of medullary thyroid cancer is frequently associated with spread to lymph nodes of the neck, in up to in up to 70% of patients. For this reason, high definition ultrasound is required in all patients with suspected or confirmed diagnosis of medullary thyroid cancer.
• The diagnosis of thyroid cancer is rarely associated with high thyroid function (hyperthyroidism) or low thyroid function (hypothyroidism).
• The diagnosis of medullary thyroid cancer which has spread to lymph nodes has a lifetime risk of spreading to distant sites of the body.
• The diagnosis of medullary thyroid cancer can frequently be effectively monitored with blood tests for both calcitonin and CEA

The Diagnosis of Medullary Thyroid Cancer that has spread to lymph nodes is Commonly Associated with Spread to Distant Areas Outside of the Neck (distant sites= distant metastases=spread to other parts of the body)

• The diagnosis of medullary thyroid cancer spread to distant sites of the body requires life-long surveillance.
• When it does spread to other areas of the body, the lungs and then bones are the most commonly found involved locations followed by the liver.
• The diagnosis of medullary thyroid cancer spread to distant sites is serious and requires an interdisciplinary thyroid cancer team that is very knowledgeable about the patient and the cancer itself.
• Distant spread of medullary thyroid cancer can make these cancers behave quite similar to other cancers that we all fear.
• Distant spread of medullary thyroid cancer may be associated with very long periods of very slow to non-detectable growth. (However this pattern can change at any time without explanation or causes).
• The diagnosis of medullary thyroid cancer spread to distant sites significantly increases the risk of dying from this thyroid cancer.
• Importantly, despite the diagnosis of medullary thyroid cancer spread to distant sites, expert surgery remains a critical part of treatment in effectively controlling where the cancer began in the thyroid as well as spread to the neck lymph nodes.
• Total thyroidectomy and central compartment dissection should be performed for all patients with a diagnosis of medullary thyroid cancer whenever feasible.
• The diagnosis of medullary thyroid cancer involving distant sites in the body is frequently associated with cancers that have spread to the neck lymph nodes. We have written several pages and also have videos so that you can understand how effective and well tolerated these comprehensive neck surgeries are in treating patients with thyroid cancer.

Diagnosis of Medullary Thyroid Cancers- Pathologic Observations

Medullary thyroid cancer

This is a representative portion of a thyroid gland. These small bluish purple cells throughout all these red encircled areas are medullary thyroid cancer cells. This will be confirmed with special pathologic studies which identify the calcitonin production of these small blue cells.

This is a photo of a lymph node which has been removed. The dark purple cells at the top of the figure are the normal lymphocytes of the lymph node. The purplish cells circled by the red cells are the medullary thyroid cancer cells which have begun to grow within the lymph node itself.

• Good surgery is the mainstay of treatment
• High risk of spread to lymph nodes throughout the neck.
• Significant lifetime risk of lung, liver and bone metastases in patients with medullary thyroid cancer spread to lymph nodes
• Readily diagnosed with fine needle aspiration (FNA) examination
• Develop from the parafollicular C cells of the thyroid.  These cells tend to be in greatest concentration in the upper portions of the thyroid gland
• The genetic defect which causes the medullary thyroid cancer is located in a gene called RET.  Only about 25% of these cancers are hereditary.
• Hereditary forms of medullary thyroid cancers may be associated with other endocrine disorders (see hereditary medullary thyroid cancer)

Diagnosis of Hereditary Medullary Thyroid Cancer

The diagnosis of the hereditary form of medullary thyroid cancer may also be associated with the following:

• A 50% risk of transferring the mutated gene to their offspring
• Predictable behavior of the medullary thyroid cancer based upon the specific RET mutation
• A family history of medullary thyroid cancer
• A family history of adrenal tumors
• A family history of sudden cardiac death
• A family history of kidney stone
• A family history of high calcium
• A family history of hyperparathyroidism or parathyroid tumors
• Editorial note: The diagnosis of papillary thyroid cancer is not commonly associated with any risk factors. (For more information see section on Papillary Thyroid Cancer Genetics and Special Cases)

Diagnosis of Papillary Thyroid Cancer: Risk Factors for Developing this Cancer

The diagnosis of papillary thyroid cancer may also be associated with the following:

• A long standing history of a lumps or nodules in the thyroid gland
• A long standing history of thyroid goiter
• A history of radiation exposure or previous radiation treatment (other than routine x rays)
• A family history of papillary thyroid cancer
• Editorial note: The diagnosis of papillary thyroid cancer is not commonly associated with any risk factors. (For more information see section on Papillary Thyroid Cancer Genetics and Special Cases)