thyroid

The thyroid gland is one of the largest endocrine glands. It is shaped like a butterfly and located at the front of the neck, below the voicebox (larynx) and on top of the windpipe (central trachea).

The thyroid gland controls how quickly the body uses energy, makes proteins, and how sensitive the body is to other hormones. These vital hormones control our metabolism, heart rate, blood pressure and body temperature.

Thyroid cancer is the fastest increasing cancer in both men and women. Unlike other cancers, its incidence rate has increased in recent years.

Thyroid cancer is now the #1 cancer in incidence in young women.

The cause of most thyroid cancer is unknown.  It is suggested that exposure to radiation from x-rays (and other forms) may be a contributing factor.

Many patients, especially in the early stages of thyroid cancer, do not experience symptoms. However, as the cancer develops, symptoms can include a lump or nodule in the front of the neck, hoarseness or difficulty speaking, swollen lymph nodes, difficulty swallowing or breathing, and pain in the throat or neck.

It is estimated that at least half of the population has thyroid nodules. Nodules need to be assessed by a physician and those that are bigger than 1 or 1.5 cm should be biopsied by an ultrasound guided fine needle aspiration (FNA) to determine if they are cancerous or not (about 95% of thyroid nodules are non cancerous).

Ultrasound guided fine needle aspiration

During a FNA, a long, thin needle is inserted through the skin and into the suspicious area. Cells are removed and analyzed to see if they are cancerous.

Thyroid cancers include the following variants:

– Papillary thyroid cancer (75% – 85% of cases)

– Follicular thyroid cancer (10% – 20% of cases)

– Medullary thyroid cancer (5% – 8% of cases)

– Anaplastic thyroid cancer, thyroid lymphoma or thyroid sarcoma (less then 5% of cases)

Almost all forms of thyroid cancer are treated primarily by surgery. In some cases, a partial thyroidectomy is performed, but for the majority of patients a total thyroidectomy is recommended. Those patients are then treated with thyroid hormone replacement therapy. In cases of metastasis to nearby lymph nodes, a neck dissection surgery is also preformed.

Some surgery risks include: Hoarseness or loss of voice (due to damage of the laryngeal nerve), low calcium levels (due to damage to parathyroid glands), bleeding and infection. With a neck dissection: numbness and/or loss of function of parts of the neck throat and shoulder, limited ability to lift one or both arms and limited ability of head and neck rotation and flexion (due to nerve, muscle, and vein damage or removal).

radioactiveFurther treatment includes radioactive iodine treatment (RAI) for patients that are at high risk for reoccurrence.

RAI treatment destroys any remaining thyroid cells (both normal and cancerous) and minimizes the risk of recurrence.

Regular surveillance consists of blood tests, regular check-ups by the doctor (feeling the neck) and imaging tests like ultrasounds or whole body scans.

 

 

Sources:

 

Wikipedia

Thyroid Cancer Canada

Thyroid Cancer Survivors’ Association

Surgery Encyclopedia