According to the National Cancer Institute, there are about 56,000 new cases of thyroid cancer in the US each year, and the majority of those diagnoses are papillary thyroid cancer—the most common type of thyroid cancer. Females are more likely to have thyroid cancer at a ratio of 3:1. Thyroid cancer can occur in any age group, although it is most common after age 30, and its aggressiveness increases significantly in older patients. Thyroid cancer does not always cause symptoms; often, the first sign of thyroid cancer is a thyroid nodule.

 

This article will highlight some common thyroid cancer signs and symptoms as well as thyroid cancer prognosis and treatments.

 

Thyroid Cancer Symptoms

 

Some thyroid cancer signs and symptoms include a hoarse voice, neck pain, and enlarged lymph nodes. Although as much as 75% of the population will have thyroid nodules, the vast majority are benign. Young people usually don't have thyroid nodules, but as people age, they're more likely to develop a nodule. By the time we are 80, 90% of us will have at least one nodule.

 

Fewer than 1% of all thyroid nodules are malignant (cancerous). A nodule that is cold on scan (shown in photo above and outlined in red and yellow) is more likely to be malignant. However, the majority of these are benign as well. You can read more information about thyroid nodules and their potential to be malignant in our articles below:

•Introduction to Thyroid Nodules

•The Workup of Thyroid Nodules and the Role of Fine Needle Aspiration (FNA) Biopsy

•The Role of Thyroid Ultrasound and What It Means

 

Talk to your doctor about any questions you have about thyroid cancer signs and symptoms.

 

 

 

Types of Thyroid Cancer

 

There are 4 main types of thyroid cancer, and some are more common than others.

 

Thyroid cancer type and incidence:

•Papillary and/or mixed papillary/follicular thyroid cancer: ~ 80%

•Follicular and/or Hurthle cell thyroid cancer: ~ 15%

•Medullary thyroid cancer: ~ 3%

•Anaplastic thyroid cancer: ~ 2%

 

Thyroid Cancer Prognosis

 

Most thyroid cancers are very curable. In fact, the most common types of thyroid cancer (papillary and follicular thyroid cancer) are the most curable. In younger patients, both papillary and follicular cancers have a more than 97% cure rate if treated appropriately. Both papillary and follicular thyroid cancers are typically treated with complete removal of the lobe of the thyroid that harbors the cancer, in addition to the removal of most or all of the other side.

 

The bottom line is that most thyroid cancers are papillary thyroid cancer, and this is one of the most curable cancers of all cancers. Treated correctly, the cure rate is extremely high.

 

Medullary thyroid cancer is significantly less common but has a worse prognosis. Medullary cancers tend to spread to large numbers of lymph nodes very early on, and therefore require a much more aggressive operation than the more localized thyroid cancers, such as papillary and follicular thyroid cancer.

 

This cancer requires complete thyroid removal plus a dissection to remove the lymph nodes of the front and sides of the neck.

 

The least common type of thyroid cancer is anaplastic thyroid cancer, which has a very poor prognosis. Anaplastic thyroid cancer tends to be found after it has spread, and it is incurable in most cases. Note: Chief Justice William Rehnquist had anaplastic thyroid cancer. You can read about anaplastic thyroid cancer in our in-depth article.

 

It is very uncommon to survive anaplastic thyroid cancer, as often the operation cannot remove all of the tumor. These patients often require a tracheostomy during the treatment, and treatment is much more aggressive than for other types of thyroid cancer.

 

Thyroid Cancer and Chemotherapy?

 

Thyroid cancer is unique among cancers. In fact, thyroid cells are unique among all cells of the human body. They are the only cells that have the ability to absorb iodine. Iodine is required for thyroid cells to produce thyroid hormone, so they absorb it out of the bloodstream and concentrate it inside the cell.

 

Most thyroid cancer cells retain this ability to absorb and concentrate iodine. This provides a perfect "chemotherapy" strategy.

 

Radioactive Iodine is given to the patient with thyroid cancer after their cancer has been removed. If there are any normal thyroid cells or any remaining thyroid cancer cells in the patient's body (and any thyroid cancer cells retaining this ability to absorb iodine), then these cells will absorb and concentrate the radioactive "poisonous" iodine.

 

Since all other cells of our bodies cannot absorb the toxic iodine, they are unharmed. The thyroid cancer cells, however, will concentrate the poison within themselves and the radioactivity destroys the cell from within—no sickness, hair loss, nausea, diarrhea, or pain.

 

Most, but not all, patients with thyroid cancer need radioactive iodine treatments after their surgery. This is important to know. Almost all patients should have the iodine treatment if a cure is to be expected.

 

Patients with medullary thyroid cancer usually do not need iodine therapy because medullary cancers almost never absorb the radioactive iodine. Some small papillary thyroid cancers treated with a total thyroidectomy may not need iodine therapy as well, but for a different reason.

 

These cancers (medullary and some small papillary cancers) are often cured with simple (complete) surgical therapy alone. This varies from patient to patient and from cancer to cancer. This decision will be made between the surgeon, the patient, and the referring endocrinologist. Remember, radioactive iodine therapy is extremely safe. If you need it, take it.