What are Thyroid Lumps & Cancer?
Thyroid lumps are solid or fluid-filled masses or bumps that develop within your thyroid. Thyroid lumps or bumps are commonly referred to as thyroid nodules. Most thyroid nodules are noncancerous (benign) and only a small percentage of them are cancerous (malignant). Thyroid cancer is a type of cancer that develops in the thyroid gland. Cancer develops when cells begin to grow out of control. People can develop thyroid lumps and cancer at any age, but they occur most often in older adults. Women are more prone to develop thyroid nodules, whereas men are more likely to develop thyroid cancer.
Anatomy of the Thyroid
The thyroid is a small, butterfly-shaped gland located in front of your neck just below the voice box (larynx). It secretes hormones that are instrumental in the proper functioning of various body parts such as the brain, heart, and muscles and help regulate your body’s metabolism such as heart rate, breathing, body temperature, weight, nervous system, blood pressure, and several other body functions. Any abnormality of this gland can cause many physiological and psychological problems in the body.
Causes and Risk Factors of Thyroid Lumps and Cancer
It is not clear what exactly causes thyroid lumps and cancer. However, several conditions can cause nodules to develop in your thyroid, including iodine deficiency, chronic inflammation of the thyroid (Hashimoto’s disease), multinodular goiter, and overgrowth of normal thyroid tissue. Although only a few thyroid nodules are cancerous, certain risk factors such as exposure to high levels of radiation to the head or neck, being male, the nodule is hard or firm, age older than 70 and younger than 20, family history of thyroid cancer, and certain inherited genetic syndromes, such as multiple endocrine neoplasias, may increase the chances of developing cancerous thyroid nodules.
Types of Thyroid Cancer
There are four types of thyroid cancer:
- Papillary thyroid cancer – Cancer that begins in the follicular cells and usually spreads slowly. It is the most common type of thyroid cancer and can be cured especially if an early diagnosis is made.
- Follicular thyroid cancer – Cancer that develops in the follicular cells and usually spreads slowly. Like papillary thyroid cancer, it can be cured with early diagnosis.
- Medullary thyroid cancer – Cancer that arises from C cells of the thyroid gland. It produces abnormally high amounts of the hormone, calcitonin. It tends to grow slowly and can be treated before spreading to the other parts of the body.
- Anaplastic thyroid cancer – Cancer that starts in the follicular cells of the thyroid and grows and spreads quickly to other parts of the body. It is the least common type but the most aggressive form of thyroid cancer.
Signs and Symptoms of Thyroid Lumps and Cancer
Thyroid lumps and cancer do not cause any signs or symptoms at an early stage. However, as the thyroid lump grows larger and cancer progresses, it can compress other structures in the neck and cause pain, swelling, difficulty in swallowing or breathing, hoarseness or change in voice, and goiter (enlargement of the thyroid gland). If the cells in the nodule produce thyroid hormones, the nodule may produce symptoms of hyperthyroidism such as sudden, unexplained weight loss, nervousness, muscle weakness, increased appetite, trouble sleeping, and rapid or irregular heartbeat. Sometimes, thyroid nodules occur in patients with Hashimoto’s disease, causing dry skin, hair loss, swelling in the face, intolerance to cold, fatigue, and unintentional weight gain.
Diagnosis of Thyroid Lumps and Cancer
Since most patients with thyroid nodules do not have symptoms, most nodules are discovered by the doctor during a routine physical examination of the neck or imaging tests. Once a nodule is discovered, your physician may recommend additional diagnostic tests to determine the condition of the nodule. These tests include:
- Fine-needle aspiration (FNA)/Thyroid biopsy: Your doctor will use a very thin needle to withdraw cells from the thyroid nodule which are examined under a microscope. This test helps to distinguish between noncancerous and cancerous thyroid nodules.
- Calcitonin blood test: This test measures the amount of the hormone calcitonin in the blood. This test can help diagnose medullary thyroid cancer as there is a high level of this hormone in the blood in this disease.
- Thyroid scan: A thyroid scan is a nuclear medicine test that allows your doctor to check how well the thyroid gland is functioning. It uses a radioactive tracer and a scanner to measure how much tracer the thyroid gland absorbs from the blood.
- Thyroid ultrasound: It uses sound waves to create images of your body. This test uses a lubricating gel and a transducer rubbed over the neck to look at the size and texture of the thyroid gland. This test can tell whether a nodule is a fluid-filled cyst or a solid mass of tissue or whether it is noncancerous or cancerous.
Treatment for Thyroid Lumps and Cancer
If a thyroid nodule is not cancerous, careful follow-up is the only recommended treatment. This follow-up may involve a repeated thyroid biopsy and an ultrasound after the diagnosis.
Sometimes, a levothyroxine (thyroid hormone) drug may be prescribed to suppress the production of the thyroid hormone if the nodule is noncancerous. Your doctor may use radioactive iodine to reduce the size and activity of the nodule in patients with overactive nodules.
Surgery may be recommended to remove the noncancerous thyroid nodule if it is causing problems with swallowing or breathing. Your physician may also contemplate surgery if you have large multinodular goiters, specifically when the goiters are constricting your airways, blood vessels, or esophagus. Nodules diagnosed as suspicious or undefined by a biopsy also require surgical removal in order to be examined for signs of cancer.
If the thyroid nodule has turned cancerous, then depending upon the type of thyroid cancer present, your doctor may choose one or more of the following thyroid cancer treatment options:
- Radiation therapy: This method uses high beams of radiation to destroy cancer cells. The patient may also take a dose of radioactive iodine to kill thyroid cells.
- Surgery: Generally, surgery is the most common treatment for thyroid cancer. Total thyroidectomy is a surgical procedure to remove all of the thyroid glands. Subtotal or partial thyroidectomy is a surgery to remove part of the thyroid gland. Your doctor may also remove the lymph nodes if cancer has spread to the nearby lymph nodes.
- Chemotherapy: It is a type of cancer treatment that uses drugs to destroy cancer cells. Chemotherapy may be used to cure cancer, slow its growth and spread, and lessen the pain. Chemotherapy is used in patients with cancer that cannot be treated with surgery or is unresponsive to radioactive iodine, as well as for patients with cancer that has spread to other parts of the body.