Thyroid

Published by Andy LoCascio at July 6, 2018

Thyroid Cancer

Overview of Thyroid Cancer

Thyroid cancer is a malignancy that originates in the butterfly shaped gland located in the front of the neck. The thyroid is responsible for the regulation of blood pressure, heart rate, body temperature and weight.

Types of Thyroid Cancer:

Papillary thyroid cancer : papillary thyroid cancer is the most common type (70-80%) of thyroid cancers. Papillary thyroid cancer tends to grow slowly and often spreads to lymph nodes in the neck.

Follicular thyroid cancer : follicular thyroid cancer (10-15% of thyroid cancers) tends to occur in older patients and often spreads to the lymph nodes in the neck. Follicular cancer sometimes also spreads to the lungs and bones.

Medullary thyroid cancer : medullary thyroid cancer (5-10% of thyroid cancers) often has a familiar genetic origin. A test for a genetic mutation in the RET proto-oncogene can lead to an early diagnosis of medullary thyroid cancer and curative surgery to remove the thyroid.

Anaplastic thyroid cancer : anaplastic thyroid cancer often presents as advanced and aggressive thyroid cancer that has spread to the lymph nodes of the neck, lungs or bones. Anaplastic thyroid cancer usually requires aggressive treatment, including tracheostomy, surgery, radiation, targeted drugs and chemotherapy.

Treatment for Thyroid Cancer

Thyroid cancer is commonly treated by one or a combination of treatments, including surgery, hormone treatment, radioactive iodine, targeted therapy, radiation therapy and/or chemotherapy.

Surgery: surgery for the removal of the tumor and surrounding tissue is the main treatment for most people with thyroid cancers.

Depending on the size of the nodule, common surgical options include:

Lobectomy: surgery that removes the gland’s lobe with the cancerous nodule. Near-total thyroidectomy: surgery to remove most of the thyroid gland. Total thyroidectomy: surgery that removes the entire thyroid gland.

The discovery of the genetic causes of familial (inherited) medullary thyroid cancer now makes it possible to identify family members carrying the abnormal RET gene and to remove the thyroid to prevent cancer from developing there.

Hormone treatment: patients who are treated with surgery for papillary, follicular, and medullary thyroid cancers usually require thyroid hormone therapy to replace necessary hormones. Thyroid hormone replacement may include levothyroxine, Levothroid, Levoxyl, Synthroid, Tirosint, or Unithroid.

Radioactive iodine (RAI) therapy: RAI Therapy (also called I-131) is a type of radiation therapy using radioactive iodine to find and destroy cancer cells that were not removed by surgery for patients with papillary and follicular thyroid cancer.

Targeted therapies: targeted drugs known as tyrosine kinase inhibitors (TKIs) may help treat thyroid cancer cells with specific gene mutations, such as BRAF and RET/PTC.

In many papillary thyroid cancers, the cells have changes in the BRAF gene, which help cancer cell growth. Drugs that target cells with BRAF gene changes include vemurafenib (Zelboraf®), dabrafenib, and selumetinib, sorafenib (Nexavar®), sunitinib (Sutent®), pazopanib (Votrient®), cabozantinib (Cometriq), motesanib (AMG 706), axitinib (Inlyta®), and vandetanib (Caprelsa®).

New targeted drugs for medullary thyroid cancer (MTC) include Vandetanib and cabozantinib.

Anti-angiogenesis drugs: Anti-angiogenesis drugs work by disrupting the ability of tumors to develop new blood vessels. Some of the TKIs, such as axitinib, motesanib, sunitinib, sorafenib, pazopanib, and cabozantinib, have anti-angiogenic properties. Other anti-angiogenesis drugs being studied for use against thyroid cancer include bevacizumab (Avastin®), lenalidomide (Revlimid®), and lenvatinib.

Chemotherapy: combination therapy of the chemotherapy drug paclitaxel (Taxol®) with the targeted drug efatutazone may be a treatment option for patients with anaplastic thyroid cancer, as well as combination therapy of chemotherapy and radiation.

For anaplastic thyroid cancer, clinical trials are studying combination chemotherapy. One study is comparing the results of either carboplatin (Paraplatin) and paclitaxel (Taxol) alone or with an experimental drug, combretastatin A4 phosphate (CA4P, fosbretabulin, Zybrestat).

Clinical Trials for Thyroid Cancer

National Cancer Institute Clinical Trials for Thyroid Cancer
http://www.cancer.gov/clinicaltrials/search/results?protocolsearchid=10591575

American Thyroid Association
http://www.thyroid.org/thyroid-trials/

Center Watch Thyroid Cancer Trial Resource
https://www.centerwatch.com/clinical-trials/listinhttp://mhony.com/wp-admin/post.php?post=7553&action=edit#gs/condition/641/thyroid-cancer

Thyroid Cancer Clinical Trial Education
http://www.cancer.net/cancer-types/thyroid-cancer/about-clinical-trials

Additional Educational Resources for Thyroid Cancer

The American Thyroid Association
www.thyroid.org

The American Thyroid Association (ATA) is the leading organization focused on thyroid biology and the prevention and treatment of thyroid disorders through excellence and innovation in research, clinical care, education and public health. The ATA Web site features a variety of FAQs and brochures for patients.
www.thyroid.org/patients/index.html

National Cancer Institute
www.cancer.gov

EndocrineWeb is a comprehensive Web site for thyroid, parathyroid and other endocrine disorders intended for the education of patients and their families. All pages were written by physicians who treat these diseases.
www.endocrineweb.com