Thyroid cancer is the fastest growing cancer in the United States, mainly due to our ability to detect these cancers with simple neck exams and ultrasounds. In fact, the incidence has doubled since the 1970’s.

Thyroid cancer is the 5^th most common cancer in women. Certainly, the diagnosis is terrifying, but thyroid cancer is very treatable, even in most patients with advanced disease. Thyroid cancer can almost always be cured through thyroid cancer surgery done in expert hands. The diagnosis is the first step in expert evaluation and treatment of thyroid cancer.

Here are the 5 best ways to diagnose thyroid cancer:

Best Way to Diagnose Thyroid Cancer #1: Fine Needle Aspiration Biopsy (FNA or needle biopsy)

Most cases of thyroid cancer have no symptoms—the person is not aware that something is happening. While a complete medical history and physical exam on a regular basis with your primary care doctor are extremely important to identify a lump or nodule in your thyroid, getting a needle biopsy of that lump remains the mainstay in the diagnosis of thyroid cancer.

• Thyroid Needle biopsy is performed by sticking a very small needle into the thyroid lump or nodule. The doctor will use an ultrasound at the same time so he/she can watch the small needle go into the thyroid nodule. When the needle is removed it will contain a small sampling of cells from the thyroid nodule (or neck lymph nodes if the needle was put into a lymph node). Looking at those cells under a microscope is how the pathologist will diagnose the thyroid cancer
• Needle biopsy is generally done on all thyroid nodules that are big enough to be felt. This means that they are larger than about 1 centimeter across (about 1/2 inch).
• Biopsies of big or abnormal appearing lymph nodes in the neck may be more informative than the thyroid nodule itself in obtaining a diagnosis of thyroid cancer.
• The process of needle biopsy (or fine needle aspiration; FNA) to diagnose thyroid cancer is as follows:
• Can usually be done in your doctor’s office or clinic.
• Before the biopsy, local anesthesia (numbing medicine) may be injected into the skin and tissue 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 times, taking samples from several areas of the nodule or lymph node.
• The content of the needle and syringe are then placed on a glass slide and the needle biopsy 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 (non-cancerous).
• Thyroid cytology (looking at cells under the microscope) requires an expert physician (cytologist) trained specifically to be able to diagnose thyroid cancer.
• Unfortunately, the diagnosis of thyroid cancer is frequently missed by unskilled or inexperienced cytologists.
• Bleeding at the biopsy site is very rare except in people with bleeding disorders or people on blood-thinning medications. Even when this occurs, the bleeding is almost always very 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 a needle biopsy will need to be repeated because the samples didn’t contain enough cells.
• Rarely, the needle biopsy may come back as benign even though a diagnosis of thyroid cancer is actually present.
• Sometimes the test results first come back as “suspicious” or “very suspicious” for a diagnosis of thyroid cancer. In such circumstances, the decision making should be in keeping with the management of a diagnosis of thyroid cancer.
• Some needle biopsy results are indeterminate or not conclusive. This means it is not exactly known if the nodule or tumor is benign (non-cancerous) or malignant (cancer). To help patients avoid unnecessary thyroid surgery, new molecular/genetic testing on the cells may be performed to help confirm an accurate diagnosis. Make sure to discuss this testing with your physician.

Browse more information regarding needle biopsy and how to diagnose thyroid cancer here.

Best Way to Diagnose Thyroid Cancer #2: Thyroid Ultrasound

A thyroid ultrasound done by a skilled and experienced team is the foundation in evaluation and diagnosis of thyroid cancer. Often, an excellent ultrasound is enough to make the diagnosis of cancer because some thyroid cancers have a very characteristic appearance on ultrasound. During ultrasound, the technician must thoroughly examine the thyroid and all the areas of lymph nodes in both sides of the neck that can be involved with thyroid cancer. If your ultrasound is not comprehensive and does not include this important component, cancer may be missed and left behind after surgery. This would lead to further surgery and treatment in the future. The best time to treat thyroid cancer is the first time. As such, a thorough evaluation along with ultrasound for diagnosis is paramount.

Ultrasound should be the first imaging test to examine a person for a potential thyroid cancer. CT scan, PET/CT scan, and MRI (very rarely) are occasionally needed as well to evaluate and diagnose if the cancer has spread outside of the thyroid and/or neck area, but those tests are never first—ultrasound is always the first test on thyroid glands. If your doctor is ordering and MRI or PET scan as the first imaging test, you need to get a second opinion from an expert ASAP. Occasionally, a CT scan is needed early in the evaluation phase, but an ultrasound is always a pillar of the diagnosis of thyroid cancer. As noted above, ultrasound is also used to guide and perform a needle biopsy of a nodule to diagnose thyroid cancer.

Best Way to Diagnose Thyroid Cancer #3: Self- Checks or Examination by a Physician

Often times, a nodule or lymph node with thyroid cancer is diagnosed on examination. Regularly performing self-checks of your neck and thyroid, coupled with routine visits to your primary doctor are crucial in diagnosis and monitoring of thyroid cancer. The thyroid is a butterfly- shaped organ that lays in the middle of your neck right above your collar bone.  It sits on top of your windpipe. Cancers that develop within the thyroid gland sometimes cause slight bulges or lumps that you can feel. Thyroid cancers can also spread to lymph nodes in the sides of your neck.  In the same fashion, performing a self-check for thyroid cancer can detect enlarged lymph nodes that have cancer. 

The way to perform a self-check for thyroid cancer would involve moving your fingers around the middle of your neck and near your windpipe, where your thyroid is located.  You also want to move your fingers up and down your neck as well as along both sides of your neck near the muscle you can see and feel that helps turn your head.  Lymph nodes that can harbor thyroid cancer are located anywhere from below your ear to your collar bone on both sides of your neck. Therefore, you would want to make sure that you are feeling the whole front and sides of your neck during your self-check for thyroid cancer. 

Another important method to diagnose thyroid cancer is regular checks with your primary doctor. Your physician will take a complete history and do a thorough physical exam as part of the thyroid cancer screening process.  When your physician is taking your history, you will be asked many questions about recent signs and symptoms. If certain symptoms like a change in voice, difficulty swallowing, or a sense of a lump in your throat are mentioned, then a formal thyroid ultrasound, as noted above, would then be ordered to potentially diagnose thyroid cancer. Learn more about thyroid cancer symptoms.

During your physical exam portion of your visit, your neck would also be felt to detect any lumps or irregularities. While your doctor is feeling your neck, he/she may feel a growth in your thyroid or an enlarged lymph node.  These findings could be indicative of a thyroid cancer and would also prompt a dedicated thyroid ultrasound and possibly a needle biopsy as discussed above. Learn more about thyroid cancer checks and screenings.

Best Way to Diagnose Thyroid Cancer #4: CT Scan

CT scan (computed tomography scan) is used more and more each year to diagnose, follow, and treat numerous medical conditions. Due to widespread, very frequent use, numerous thyroid cancers are found incidentally (or coincidentally) when someone gets a CT scan of their head, neck, and/or chest for another symptom or complaint (i.e. headache, neck pain, or difficulty breathing). CT scans are great for a zoomed- out look or overview of a thyroid cancer in relation to other structures in the neck.

CT scan produces detailed images of your body. The scanner takes many pictures while you lie on the table. A computer then combines these pictures into images or slices of the part of your body being studied (similar to a loaf of bread) from the bottom of your brain to the middle of your chest. This can help diagnose and determine the location and size of thyroid cancers, whether the cancer has invaded into any nearby structures, and whether it 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 or brain. Before the test, you will be asked to receive contrast dye in a vein (intravenous or IV). This helps better outline structures in your body. Be sure to tell the doctor if you have any allergies or have ever had a reaction to any dye used for other imaging studies or scans.

This cannot be stressed enough, but the ultrasound tells the doctor if there is something abnormal in the thyroid (diagnose thyroid cancer). The CT scan can further tell the doctor where the abnormality is located! Both studies complement each other. The CT scan of the neck also can look at areas that the ultrasound cannot study because sound 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 sometimes be quite limited, and therefore a CT scan may provide valuable additional information regarding where the thyroid cancer is located.

Best Way to Diagnose Thyroid Cancer #5: Blood Tests

Only a small percentage of thyroid cancers are diagnosed directly with blood tests. The most common type of thyroid cancer, papillary, which accounts for roughly 85% of cases, cannot be diagnosed with labs. A rarer type, medullary thyroid cancer, can be diagnosed with 2 markers in the blood: calcitonin level, and CEA level (carcinoembryonic antigen). Because medullary thyroid cancer is very infrequent, these blood tests are not routinely used to screen for thyroid cancer. Normal thyroid hormone levels on your labs does not rule out thyroid cancer!

The significance of checking thyroid lab tests during your thyroid cancer screening is that abnormal thyroid levels should always prompt an ultrasound. During this ultrasound, a cancerous thyroid nodule or lymph node could be found. Evaluation and diagnosis of thyroid cancer involves a complete history and physical, as noted above, along with a complete blood panel that includes thyroid labs. You may have heard of another thyroid cancer marker, thyroglobulin, that can be checked or followed after treatment of thyroid cancer. This is a protein made by normal thyroid cells along with thyroid cancer cells in many instances. As such, this level can be followed to diagnose cancer coming back after someone has their entire thyroid gland removed.

Bonus: Best Way to Diagnose Thyroid Cancer #6: MRI, Nuclear Medicine Thyroid Uptake & Scan, and PET/CT Scans

The following imaging tests are used less frequently in diagnosis of thyroid cancer. They are also used in diagnosis of other thyroid conditions. Please read below for brief summaries of these imaging tests.

• MRI (magnetic resonance imaging)
  • Sometimes used instead of CT scan to evaluate the thyroid cancer and if there is spread to other areas or structures in the neck. 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 very detailed images. A contrast dye called gadolinium is often injected into a vein before the scan to better show detailed pictures.

• Nuclear Medicine Thyroid Uptake & Scan (nuclear medicine thyroid scan or radioactive iodine uptake test)
  • This study is done to evaluate the function of the thyroid gland and/or a nodule when there is concern for overactivity. Because the thyroid gland normally takes up iodine in order to make thyroid hormone, measuring how much radioactive iodine is captured by the gland can be a very useful way to measure its function. The dose of radiation with these tests is very small and has no side effects. You will be given radioactive iodine (I-123 or I-131) in liquid or capsule form to swallow. The thyroid uptake will begin several hours to 24 hours later. Often, two separate uptake measurements are obtained at different times. For example, you may have uptake measurements at four to six hours and 24 hours. Thyroid cancers show up as “cold” or underactive nodules on these scans.

• PET (positron emission tomography) Scan or PET/CT scan
  • These imaging tests are done frequently to see if thyroid cancer has spread outside of the neck to other parts of the body or to diagnose thyroid cancer returning. Often the PET scan is combined with a CT scan to get good pictures for the anatomical location of the thyroid cancer. 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 more sugar as their energy source to grow, they absorb more of the sugar than normal cells and this causes them to light up on the PET scan.

Summary

The diagnosis of thyroid cancer starts with a thorough history and physical exam. Self-exam and regular, routine follow-up with your primary doctor are also important to diagnose thyroid cancer. Next, and excellent thyroid ultrasound to examine the thyroid and lymph nodes in the neck is paramount. While thyroid cancer is being diagnosed more frequently, almost everyone with thyroid cancer has normal thyroid levels on blood tests. That is to say, the vast majority of thyroid cancers are not discovered or diagnosed directly by blood tests. Finally, CT scan and PET/CT scan are two other imaging tests to diagnose thyroid cancer. Expert evaluation and diagnosis of thyroid cancer is crucial!

Additional Resources

• Become our patient at www.thyroidcancer.com/become-a-patient
• More about the The Clayman Thyroid Center at thyroidcancer.com/about
• More about the Hospital for Endocrine Surgery
• Scarless Thyroid Surgery for thyroid cancer