What is a Thyroid?

The thyroid is a butterfly-shaped gland located in the front part of the neck, below the Adam’s apple. In most people it cannot be seen or felt. The thyroid gland takes iodine (a mineral found in iodized salt and some foods) from the diet and blood and uses it to make several of the hormones that it produces and stores. Some of those hormones help regulate heart rate, body temperature, blood pressure and the rate that food is converted into energy.

It consists of two lobes, the right and the left, and is joined by a narrow isthmus. The lobes resemble the wings of a butterfly and the isthmus represents the body. The thyroid is normally larger in women during menstruation and pregnancy.

Thyroid Cancer

Thyroid cancer accounts for approximately 1% of all cancers, with around 12,000 Americans being diagnosed each year.

The thyroid gland contains two main types of cells: C cells, which make a hormone known as calcitonin, and the thyroid follicle cells, which make a thyroid protein called thyroglobulin and do the actually creating and storing of the thyroid hormone.

Cancer develops differently in each cell. Cancer is formed when the body’s cells begin to reproduce in a rapid and haphazard manner, causing an abundance of some and a shortage of others. The excess creates a mass of tissue known as a tumor.

A bump in the neck (thyroid nodule) is often the first sign of a thyroid tumor because the thyroid gland is so close to the skin. They can appear at any age but are found more often in adults.

Most tumors (over 90%) found in the thyroid gland tend to be benign (non-cancerous). Benign thyroid nodules develop from the follicular cells and can be found in both enlarged and normal-sized glands, in multiple numbers or singular. If the gland has more than one nodule, it is called a multinodular goiter.