Symptoms of Thyroid Cancer
Thyroid cancer is the fifth most common cancer in women in the United States, and according to the National Cancer Institute, there will be a total of nearly 54,000 new cases of thyroid cancer occurring in women and men in 2018.
Thyroid cancer most commonly begins as a growth (called a nodule) in the thyroid gland, which is located in the lower, front part of your neck. Usually, the nodule does not cause any symptoms; although if large enough, the thyroid nodule may cause pain or difficulty swallowing or breathing.
Many people with thyroid cancer do not have symptoms. Instead, these cancers are discovered incidentally by a primary care or family doctor during a routine neck examination or by an imaging test performed for other purposes (for example, a CT scan of the neck or a carotid ultrasound).
If symptoms are present, the most common one is the presence of a new thyroid growth or swelling, called a thyroid nodule. While a fine-needle aspiration biopsy is often used to determine if a thyroid nodule is malignant (cancerous) or benign (non-cancerous), certain symptoms and signs may increase the doctor’s suspicion that the nodule is malignant.
These symptoms and signs include:
- The rapid growth of the nodule within a short period of time
- Nodule that feels “stuck” or tightly attached to the surrounding tissue
- Presence of lymph node swelling in the neck on the same side as the nodule
Besides the presence of a thyroid nodule, other potential symptoms of thyroid cancer (although these are not common) include:
- Pain in the front of the neck (where the thyroid gland is located) that may “move” or radiate up to the jaw or ears
- A persistent “tickle in the throat”
- Problems swallowing if the thyroid nodule gets too large and presses on your esophagus (the tube that connects your throat to your stomach)
- Problems breathing if the nodule gets too large and presses on your windpipe
- A persistent cough without other cold symptoms
- Coughing up blood
- Hoarseness, if the cancer invades into the nerve the controls the vocal cords
It’s important to mention that with medullary thyroid cancer, which accounts for only 1 percent to 2 percent of all thyroid cancers, a person may experience symptoms like diarrhea, itching, and flushing (if the cancer has spread throughout the body).
These symptoms occur as a result of the production of calcitonin, which is a hormone made by thyroid “C” cells. Medullary thyroid cancer originates from these “C” cells, unlike the other types of thyroid cancer which originate from thyroid follicular cells (the cells that make thyroid hormone).
Thyroid cancer that spreads (called metastasis) outside of the neck is not typical, but it does happen if the tumor is not detected and treated early.
Moreover, it’s worth mentioning that metastasis is most likely to occur with anaplastic thyroid cancer, which is a very rare, but aggressive type of thyroid cancer, accounting for less than 1 percent of all cases. Symptoms of anaplastic thyroid cancer include a rapidly growing neck lump that is large and firm, as well as hoarseness, problems swallowing and problems breathing.
Lung and Bone Metastasis
If there is any distant spread with thyroid cancer, the most common organs are the lungs and bones. Lung metastasis may cause a variety of symptoms like trouble breathing, shortness of breath, chest pain, or cough, whereas bone metastasis may cause bony pain, fractures, and spinal cord compression.
Even rarer, thyroid cancer may spread to the brain. Experts guess this occurs in 0.1 to 5 percent of all cases of papillary thyroid cancer (the most common type of thyroid cancer).
Symptoms of brain metastasis vary according to where in the brain the metastatic lesion(s) is present. For example, in one case study in Head and Neck Oncology, a 75-year old woman developed gradual dizziness, headache, and vomiting and was found to have metastatic thyroid cancer to an area of her brain called the cerebellum (a region of the brain that helps control movement and coordination).
If you feel a new swelling or lump in your neck, or if an imaging test incidentally reveals a thyroid growth, it’s important to schedule an appointment with your doctor right away.
During your appointment, your doctor will perform a physical examination, including a neck examination, order an ultrasound of your thyroid, and check blood tests for other types of thyroid diseases. These blood tests may include a thyroid stimulating hormone (TSH), free thyroxine (T4), and thyroid antibodies.
Depending on the results of these tests (for example, if a thyroid nodule is found), your primary care or family doctor may refer you a doctor who specializes in thyroid care (called an endocrinologist). An endocrinologist may take another look at the thyroid nodule with an ultrasound in his or her office and perform a fine-needle aspiration (FNA) biopsy to see whether cancer cells are present.
Keep in mind, the incidence of thyroid cancer has been on the rise both in the United States and worldwide, due in large part to the sophistication of high-resolution imaging tests. In other words, these thyroid nodules that would never have been found years ago are now being identified.
Regardless, while the majority of these small nodules end up not being cancer, determining which ones are is key—this is because most thyroid cancers are curable, especially those that are small and have not spread.
On a final note, if you have a family history of medullary thyroid cancer, be sure to talk to your doctor. Through a genetic counselor, you can undergo genetic testing to see if you carry the gene mutations connected to medullary thyroid cancer.