What is Thyroid Cancer?

Thyroid cancer is a type of cancer that develops in the thyroid gland. The thyroid gland is present in the front part of the neck just below the Adam's apple (or the thyroid cartilage). It is a butterfly shaped gland, which has 2 lobes (the right lobe and the left lobe). The two lobes are joined by a narrow piece of tissue called the isthmus. The gland is small and hence, in most people, it cannot be seen or felt.

The 2 main types of cells that make the thyroid gland include:

• Thyroid follicular cells: These cells synthesize the important hormone called the thyroid hormone. The hormone plays an important role in regulating a person's metabolism.
• C cells (parafollicular cells): These make a hormone known as calcitonin (the hormone regulates use of calcium in the body).

The less common cells present in the thyroid gland are immune system cells (lymphocytes) and supportive (stromal) cells. Cancer can develop from any of these cells. It is important to identify the type of cell from which the cancer has originated as it affects the extent of cancer that impinges and the type of treatment that may be needed.

Both benign (non-cancerous) and malignant tumors (cancers that can spread into nearby tissues and to other parts of the body) can develop in the thyroid gland. The four major types of thyroid cancer that develop in the thyroid include:

• Papillary carcinoma: 78%.
• Follicular carcinoma:17%.
• Medullary carcinoma:4%.
• Anaplastic carcinoma:1%.

Thyroid cancer occurs more commonly in women as compared with men (it is three times more common in women). The exact cause of thyroid cancer is not known in most cases, but, certain factors are known to increase the risk of thyroid cancer. Risk factors for thyroid cancer include family history of goiter, exposure to high levels of radiation and certain hereditary syndromes.

Most people diagnosed with thyroid cancer in its early stage, do not have symptoms. Some common signs and symptoms of this cancer are a lump or thyroid nodule in the neck, difficulty in swallowing, throat or neck pain, swollen lymph nodes in the neck, cough and change of voice. Similar symptoms, however, can be caused by many non-malignant conditions of the thyroid. The definite way to confirm if the thyroid nodule is cancerous or not is by undergoing a thyroid tissue biopsy (needle biopsy or surgical biopsy).

Treatment options for thyroid cancer include surgery, radiation therapy, chemotherapy and radioactive iodine treatment. Most cases are treated with surgery. Your doctor, after performing examinations and tests, can determine the best treatment option for you. Most cases with thyroid cancer have a good prognosis.