What Is Thyroid Cancer?
Thyroid cancer is a form of cancer that starts in the thyroid gland located in the front, lower portion of the neck. While anyone can develop thyroid cancer, Medline Plus states that certain groups of people are at higher risk for the health condition. Surgery is the most commonly used method for treating cancer of the thyroid gland.
- Individuals between the ages of 25 and 65
- Individuals who have undergone radiation treatments
- Individuals of Asian descent
- Chronic goitre
Surgery is the most common treatment of thyroid cancer – one of the following procedures may be used:
Thyroid Lobectomy – Removal of the lobe in which thyroid cancer is found. Biopsies of lymph nodes in the area may be done to see if they contain cancer
Near-total thyroidectomy – Removal of all but a very small part of the thyroid
Total thyroidectomy – Removal of the whole thyroid
Lymphadenectomy – Removal of lymph nodes in the neck that contain cancer
A thyroid surgeon will be able to determine the most appropriate treatment plan if it is found that you have thyroid cancer or any other thyroid condition. On that note, keep in mind that many thyroid conditions are non-cancerous and can be treated with less invasive methods. Additional treatment methods for cancer of the thyroid include radiation therapy, chemotherapy, targeted therapy, and thyroid hormone therapy. In many cases, individuals are able to beat cancer by taking drugs designed to attack cancerous cells without affecting the healthy cells of the body. Other forms of therapy stop cancerous cells from multiplying. The type of treatment that will work best for you will depend on variables including how extensive the cancer is.
In addition to seeking the professional guidance and care of a thyroid surgeon in Sydney, you can seek the emotional support that you may need through cancer support groups. It is also important to continue taking thyroid hormone replacement medications after surgery and to maintain a healthy lifestyle so that you are able to optimize your overall health. If you have any questions about thyroid symptoms or thyroid surgery, you should speak to your local doctor, who will arrange to contact your thyroid surgeon.
Radiation therapy, including radioactive iodine therapy
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.
Radiation therapy may be given after surgery to kill any thyroid cancer cells that were not removed. Follicular and papillary thyroid cancers are sometimes treated with radioactive iodine (RAI) therapy. Higher doses than the amounts used to diagnose thyroid cancer are used. RAI is taken by mouth and collects in any remaining thyroid tissue, including thyroid cancer cells that have spread to other places in the body. Since only thyroid tissue takes up iodine, the RAI destroys thyroid tissue and thyroid cancer cells without harming other tissue. Before a full treatment dose of RAI is given, a small test-dose is given to see if the tumor takes up the iodine.
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy).
Chemotherapy is not usually used to treat differentiated thyroid cancer. However, certain chemotherapy drugs are useful in combination with external radiation beam therapy for anaplastic thyroid cancers. Chemotherapy is also used sometimes for thyroid cancers that have continued to grow after treatment with radioactive iodine or external beam radiation therapy.
Up to 25% of recurrences and metastases from well-differentiated thyroid cancer may not show I131 uptake. For these patients, other imaging techniques shown to be of value include imaging with thallium-201, magnetic resonance imaging, and PET scanning. When recurrent disease does not concentrate I131, external-beam or intraoperative radiation therapy can be useful in controlling symptoms related to local tumor recurrences. Systemic chemotherapy can also be considered. Chemotherapy has been reported to produce occasional objective responses, usually of short duration.
Targeted therapy can be considered as a type of chemotherapy and a phase II study looked at the activity of sorafenib. Sorafenib is an orally active, multityrosine kinase inhibitor that affects tumor cell proliferation and angiogenesis. In this study the drug was administered to 30 patients with advanced iodine-refractory thyroid cancer. Among 25 assessable patients, there were 7 patients with partial responses and 16 patients with stable disease. The progression-free survival for differentiated thyroid cancer patients was 84 weeks. Further investigation of this approach is warranted.
Thyroid hormone therapy
Hormone therapy is a cancer treatment that removes hormones or blocks their action and stops cancer cells from growing. Hormones are substances made by glands in the body and circulated in the bloodstream. In the treatment of thyroid cancer, drugs may be given to prevent the body from making thyroid-stimulating hormone (TSH), a hormone that can increase the chance that thyroid cancer will grow or recur. Also, because thyroid cancer treatment kills thyroid cells, the thyroid is not able to make enough thyroid hormone. Patients are given thyroid hormone replacement pills.
Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Tyrosine kinase inhibitor (TKI) therapy is a type of targeted therapy that blocks signals needed for tumors to grow. Multityrosine kinase inhibitors may be used to treat patients with advanced iodine-refractory thyroid cancer as part of a clinical trial.
Thyroid cancer treatment summary
- Total thyroidectomy is recommended for papillary (>1.5cm), follicular, Hurtle cell and medullary carcinomas
- Appropriate neck dissection surgery is recommended to address lymph node involvement
- Following surgery patients with papillary or follicular thyroid cancer are usually treated with radioactive iodine to address potential residual disease.
- All patients should be maintained on suppressive doses of thyroid hormone.
- For patients with undifferentiated thyroid cancer treatment usually requires a combination of surgery, chemotherapy and radiotherapy