Thyroid cancer may not be as widely talked about as other types of cancer. Still, knowing thyroid cancer symptoms and early warning signs of thyroid gland cancer is important for timely diagnosis and treatment. Here’s what you need to know.
Where Is Your Thyroid Gland?
The thyroid gland is butterfly-shaped. It has two distinctive lobes on either side of the trachea (windpipe) connected by a narrow piece of thyroid tissue called the isthmus.
Located at the front of the neck, your thyroid gland lies directly below your voice box (larynx) and on top of your windpipe (trachea). Its position just below the Adam's apple makes it relatively superficial, meaning it's closer to the skin's surface. As such, it can often be felt or seen as a bulge when enlarged.
Thyroid Hormones and Their Functions
The thyroid gland is an essential organ within the endocrine system. It produces and secretes hormones that help regulate metabolic processes throughout your body.
Hormones Produced by Your Thyroid Gland
The thyroid gland, its functions, and hormones include the following:
Thyroxine (T4): The primary hormone produced by the thyroid gland. T4 is considered a prohormone as it has a weaker hormone activity than T3. However, it serves as a reservoir for producing the more potent T3.
Triiodothyronine (T3): The most active thyroid hormone significantly affecting various bodily functions. Though the thyroid produces some T3 directly, most of the T3 in the body comes from converting T4 into T3 by deiodinase enzymes found in many tissues throughout the body.
Calcitonin: Produced by the C-cells of the thyroid gland, calcitonin is involved in calcium homeostasis. It lowers calcium levels in the blood by inhibiting the activity of cells that break down bone.
Hormones Influenced by Your Thyroid
The hormones produced by the thyroid gland do not act alone; they also interact with other hormones to maintain balance (equilibrium):
- Thyroid-stimulating hormone (TSH): While not produced by the thyroid gland, TSH is released by the pituitary gland and regulates the production of T4 and T3 by the thyroid. It’s part of a feedback system that maintains hormonal balance.
- Thyrotropin-releasing hormone (TRH): Produced by the hypothalamus, TRH stimulates the pituitary gland to release TSH. It's another key component of the regulatory feedback system.
- Insulin and glucagon: Thyroid hormones interact with insulin and glucagon to help regulate blood sugar levels.
- Growth hormones: Thyroid hormones work with growth hormones to ensure proper development and metabolism.
- Sex hormones: Thyroid function can influence the levels of sex hormones, thus affecting various reproductive functions.
- Cortisol: The body’s stress response and metabolism can be affected by the interaction between cortisol and thyroid hormones.
What Are the Early Warning Signs of Thyroid Cancer?
While thyroid cancer symptoms are what a patient feels and describes, thyroid cancer signs are the observable and objective indicators. Both are critical in diagnosing and managing medical conditions, but they differ in their nature and how they are assessed.
Neck lumps: A noticeable lump in the front of the neck is a common early sign of thyroid cancer. The lump may rapidly grow or remain stable in size. Thyroid nodules are neck lumps that specifically form within the thyroid gland. Most thyroid nodules are benign. However, some can be cancerous.
Visible changes in the thyroid gland: The thyroid gland may appear enlarged or asymmetrical, and its surface may be irregular or bumpy.
Voice changes: Hoarseness, persistent cough, or difficulty swallowing can be signs of thyroid cancer if the cancer affects the nerves that control the voice box or esophagus.
Visible changes in the skin: Redness, swelling, or ulceration of the skin over the thyroid gland can be a sign of advanced thyroid cancer that has broken through the skin.
Swollen lymph nodes: In the case of thyroid cancer, the disease can sometimes spread from the thyroid gland to the lymph nodes, which can cause them to become swollen or enlarged. This is known as lymph node metastasis. The lymph nodes in the neck that might be swollen due to thyroid cancer typically include:
- Cervical lymph nodes along the sides of the neck are the most common sites of metastasis for thyroid cancer.
- Supraclavicular lymph nodes are just above the clavicle (collarbone); these can enlarge if cancer spreads in the lymphatic system.
- Pretracheal and paratracheal lymph nodes are located in front of and beside the trachea (windpipe) and can be affected by thyroid cancer.
- Retropharyngeal lymph nodes are behind the pharynx (throat). Although less commonly involved, they can be affected by the spread of thyroid cancer.
Thyroid Cancer Symptoms: What Are the Most Common Red Flags?
Symptoms of thyroid cancer are subjective experiences that you, as a patient, experience and should report to your doctor. These symptoms may include:
Unexplained fatigue: Feeling fatigued or tired all the time can be a sign of thyroid cancer, especially if accompanied by other symptoms.
Neck pain: Pain in the front of the neck, sometimes extending to the ears, can be a sign of thyroid cancer, especially if the cancer is large or has spread to nearby tissues.
Unexplained weight changes: Unexplained weight loss or gain can be a sign of thyroid cancer, particularly if the cancer is affecting the thyroid's production of hormones.
Difficulty swallowing: A sensation of food getting stuck in the throat or neck can be a sign of thyroid cancer if the enlarged thyroid gland is putting pressure on the esophagus.
Difficulty breathing: Difficulty catching your breath or feeling like you're not getting enough air can be a sign of thyroid cancer if the cancer is causing compression of the trachea or other airways.
Changes in menstrual cycle: Irregular menstrual periods, heavier bleeding, or bleeding between periods can be a sign of thyroid cancer in women.
Psychological symptoms: Anxiety, depression, or irritability can be associated with thyroid cancer, particularly if the cancer is causing significant hormonal changes.
What Are Different Types of Thyroid Cancer?
Thyroid cancer categories are based on the types of cells found in the tumor. Each thyroid cancer type can have a different prognosis and may affect thyroid cancer treatment choices.
Papillary thyroid cancer (PTC) accounts for about 80-85% of all thyroid cancer cases. It typically grows very slowly and often affects only one lobe of the thyroid gland. A family history of thyroid cancer can further increase your risk of getting PTC.
Follicular thyroid cancer is the second most common type of thyroid cancer, comprising about 10-15% of all cases. It's more likely to spread and metastasize to distant organs than papillary cancer.
Medullary thyroid cancer (MTC) makes up about 3-4% of thyroid cancers and can be sporadic or inherited. It develops from the C cells of the thyroid and often over-secretes calcitonin. When taken for 2 to 3 years, GLP-1 receptor antagonists for treating type 2 diabetes and weight loss (brand names Mounjaro, Ozempic, and Wegovy) may increase the risk of developing MTC. If you have a family history of MTC, your risks further increase.
Primary thyroid lymphoma is a very rare type of thyroid cancer that originates in the immune system cells in the thyroid and tends to grow quickly. Primary thyroid lymphoma is rare but more likely to occur in people who have Hashimoto's thyroiditis, which is a potential cause of thyroid pain.
Anaplastic thyroid cancer (ATC) is a rare and aggressive form of thyroid cancer in about 2% of thyroid cancer cases. It's one of the fastest-growing and most aggressive cancers. Risk factors are unknown for this type of thyroid cancer, but it’s more common in women ages 60 or older.
What Are the Most Common Risk Factors for All Types of Thyroid Cancer?
Several factors can heighten the risk of developing thyroid cancer. These risk factors include the following.
Radiation exposure: High levels of radiation, such as when radiation is used to treat head or neck cancers, can increase the risk of thyroid cancer later on. This risk is particularly high for children who were exposed to radiation before the age of 10.
Iodine deficiency: Iodine is an essential nutrient the thyroid gland needs to produce hormones. While most people get enough iodine in their diets, about 30% of the world’s population still needs iodine supplementation. Iodine deficiency can lead to an enlarged thyroid gland (goiter), which can increase the risk of thyroid cancer.
Hormonal factors: Women are more likely to develop thyroid cancer than men. This may be due to the effects of estrogen, a female hormone. Pregnancy and menopause can also increase the risk of thyroid cancer.
Diet: Some research suggests that a diet high in processed meats and low in fruits and vegetables can increase the risk of various forms of cancer, including thyroid cancer. However, more research is needed to confirm these findings.
Smoking: Smoking may increase the risk of thyroid cancer. This is likely because smoking can damage cells and DNA.
It’s worth noting that certain genetic syndromes can increase the risk of developing thyroid cancer. Genetic testing may help determine if you have inherited syndromes associated with a higher risk of thyroid cancer.
Some of these genetic conditions include:
- Multiple endocrine neoplasia
- Cowden syndrome
- Familial adenomatous polyposis
- Acromegaly
- Familial adenomatous polyposis
- Li-Fraumeni syndrome
- Cowden syndrome
- Carney complex
- DICER1syndrome
Can Blood Tests Detect Thyroid Cancer?
Blood tests typically monitor levels of thyroid hormones to evaluate thyroid function, but these are not specific to cancer. However, liquid biopsy is a more advanced blood test for finding cancer cells or fragments of DNA from cancer cells (circulating tumor DNA) in the blood. This technique could potentially detect thyroid cancer early in the disease process.
Research is ongoing and this method is not yet standard practice for thyroid cancer diagnosis. However, it represents a significant step forward in cancer care. The ability to detect cancer cells or their DNA through a simple blood draw could allow for earlier and less invasive diagnosis than traditional methods.
Currently, the most reliable method for diagnosing thyroid cancer involves a combination of a physical exam, imaging tests such as a thyroid ultrasound, magnetic resonance imaging (MRI), or computed tomography (CT scans), and ultimately a thyroid biopsy. If a thyroid nodule is detected, a fine needle aspiration biopsy will extract cells from the nodule for examination under a microscope. This is how the presence of cancer cells is confirmed.
Additional tests, such as radioactive iodine scans, can also be conducted to assess whether the cancer has spread to nearby lymph nodes or other areas in the body. Once a cancer diagnosis is established, treatment options may include thyroidectomy (surgical removal of the thyroid gland), hormone therapy to replace or suppress thyroid hormone production, radiation therapy, or radioactive iodine treatment, depending on the type and stage of the cancer.
The American Cancer Society underscores the importance of follow-up after treatment for thyroid cancer to monitor any changes in thyroid hormone levels and manage any potential side effects of treatment.
How Long Can You Have Thyroid Cancer Before You Know It?
When thyroid cancer causes symptoms, it often manifests as a growth (called a "nodule") on the thyroid gland. The thyroid nodule could grow quickly or slowly, which is why it’s important to be vigilant — especially if you have a family history or any risk factors mentioned above. You can also evaluate your risk factors with Ezra’s risk factor calculator which is fast, free, and easy to use.
Here’s the good news: By having a thyroid MRI as part of a larger MRI screening like the Ezra Scan, radiologists can detect abnormalities or changes in your thyroid (by comparing earlier Ezra Scans) before symptoms appear.
Waiting for symptoms to emerge can result in missed opportunities for early detection and treatment. Since thyroid cancer may remain dormant for a considerable period, relying on symptomatic cues is not the most effective strategy for early detection.
By the time any symptoms appear, the cancer may have advanced to a more serious stage, potentially complicating treatment and affecting the prognosis.
Discover the Peace of Mind You Get from Proactive Screening
Early detection of thyroid cancer significantly increases the chances of successful treatment. When caught early, the majority of thyroid cancers are treatable and patients often have more treatment options with fewer complications. Early-stage thyroid cancers can typically be managed with less aggressive treatments and have higher survival rates.
Ezra recognizes the importance of early detection and has developed specialized MRI scans designed for cancer screening purposes. The Ezra Full Body scan can detect abnormalities in the thyroid gland and up to 12 other body parts before symptoms arise.
Book an Ezra scan to be proactive about your health and get the peace of mind you deserve.
