Thyroid Cancer Treatment Hormone

Surgery for thyroid cancer involves either partially or completely removing the thyroid gland. Following this procedure, patients need hormone treatment to maintain adequate thyroid hormone levels. Thyroid hormone treatment has two primary goals:

  • Replacement therapy: Replaces missing thyroid hormones
  • Suppression therapy: Prevents growth of thyroid cells and a recurrence of thyroid cancer.

Hormone Replacement Therapy

Thyroid hormones regulate the body’s metabolism and are essential for overall health. When all or a portion of the thyroid is removed as part of the treatment plan for thyroid cancer, the body stops producing enough of the hormones and thyroid levels can go too low. The signs and symptoms of hypothyroidism — abnormally low thyroid hormone levels — can result, including:

  • Dry skin and hair
  • Fatigue
  • Physical slowness
  • Weight gain.

Thyroid hormone treatment helps restore metabolic balance to your body. Your doctor will work with you to determine the proper dose of synthetic thyroid hormone needed to get your thyroid hormone levels back to normal. Thyroxine, or T4, is the most commonly prescribed thyroid hormone replacement.

Suppression Therapy: How Thyroid Stimulating Hormone (TSH) Works

Thyroid hormone treatment not only stabilizes your thyroid levels, it can also help prevent thyroid cancer recurrences. Thyroid growth is promoted by TSH (thyroid stimulating hormone), which is produced by the pituitary gland depending on how much thyroid hormone is in the blood. If thyroid hormone levels are low, TSH production ramps up to kick the thyroid into gear. Doctors have found that by keeping thyroid hormone levels high, they can keep TSH levels low, which slows the growth of potentially cancerous thyroid cells.

Once the correct dose of thyroid hormone is determined, thyroid hormone treatment generally has few side effects. However, some physicians are concerned about the possible long-term effects of maintaining elevated thyroid hormone levels. These can include an increased risk of:

  • Decreased bone density
  • Exacerbated chest pain
  • Fast, irregular heart rate.

Monitoring Thyroid Levels

Thyroid hormone treatment is usually administered in the form of a pill taken once a day. Many patients take their medication at the same time every day to get into the habit of taking their meds regularly.

Most patients who start thyroid hormone treatment stay on it for the rest of their lives, and regularly visit the doctor for check-ups. Your doctor will conduct a physical exam and run blood tests to monitor your thyroid hormone levels and the amount of TSH in your bloodstream. Over time, your medication may be adjusted to ensure proper thyroid functioning and minimal side effects.


American Thyroid Association Staff. (2005). Thyroid hormone treatment. Retrieved March 28, 2010, from the American Thyroid Association Web site:

American Cancer Society Staff. (2009). Thyroid cancer: Thyroid hormone therapy. Retrieved March 28, 2010, from the American Cancer Society Web site:

Macmillan Cancer Support Staff. (2007). Thyroid hormone replacement after surgery for thyroid cancer. Retrieved March 28, 2010, from the Macmillan Cancer Support Web site: Treatingthyroidcancer/Thyroidhormonereplacement.aspx.

Brigham and Women’s Hospital Staff. (2009). Thyroid hormone replacement therapy. Retrieved March 28, 2010, from the Brigham and Women’s Hospital Web site:,P00433.