The thyroid is the butterfly-shaped gland at the base of the neck. The thyroid gland is a vital hormone gland. It plays a major role in the metabolism, growth and development of the human body. It helps to regulate many body functions by constantly releasing a steady amount of thyroid hormones into the bloodstream. The thyroid produces hormones that regulate heart rate, blood pressure, body temperature and weight.

Thyroid cancer is a growth of cells that starts in the thyroid. Having an overactive thyroid gland (hyperthyroidism) or an underactive thyroid gland (hypothyroidism) doesn't increase your chances of developing thyroid cancer. Around 1 in 5 cases of thyroid cancer occur in people who've had a previous benign thyroid condition.  The exact cause of most thyroid cancers is not yet known. Certain changes in a person's DNA can cause thyroid cells to become cancerous.

 For unclear reasons thyroid cancers (like almost all diseases of the thyroid) occur about 3 times more often in women than in men. Thyroid cancer can occur at any age, but the risk peaks earlier for women (who are most often in their 40s or 50s when diagnosed) than for men (who are usually in their 60s or 70s.

Signs and Symptoms of Thyroid Cancer

·         A lump in the neck, sometimes growing quickly.

·         Swelling in the neck.

·         Pain in the front of the neck, sometimes going up to the ears.

·         Hoarseness or other voice changes that do not go away.

·         Trouble swallowing.

·         Trouble breathing.

·         A constant cough that is not due to a cold.

Types of thyroid cancer include:

• Papillary: Up to 80% of all thyroid cancers are papillary. This cancer type grows slowly. Although papillary thyroid cancer often spreads to lymph nodes in your neck, the disease responds very well to treatment. Papillary thyroid cancer is highly curable and rarely fatal.

• Follicular: Follicular thyroid cancer accounts for up to 15% of thyroid cancer diagnoses. This cancer is more likely to spread to your bones and organs, like your lungs. 

•  Medullary: About 2% of thyroid cancers are medullary. A quarter of people with medullary thyroid cancer have a family history of the disease.

• Anaplastic: This aggressive thyroid cancer is the hardest type to treat. It can grow quickly and often spreads into surrounding tissue and other parts of your body. This is a rare cancer.

DIAGNOSIS AND TESTS

Physical exam:  Physical examination of  your neck to feel for changes in your thyroid, such as a lump (nodule) in the thyroid and may also ask about your risk factors, such as past exposure to radiation and a family history of thyroid cancers.

Thyroid function blood tests: that measure blood levels of thyroid-stimulating hormone (TSH) and hormones produced by your thyroid gland might give your health care team clues about the health of your thyroid.

Ultrasound imaging: Signs that a thyroid nodule is more likely to be cancerous include calcium deposits (micro calcifications) within the nodule and an irregular border around the nodule.

Biopsy:  Removing a sample of thyroid tissue. Fine-needle aspiration for biopsy

Management and Treatment 

Thyroid cancer treatment options depend on the type and stage of your thyroid cancer. Most people diagnosed with thyroid cancer have an excellent prognosis, as most thyroid cancers can be cured with treatment

Treatment might not be needed right away for very small papillary thyroid cancers (papillary micro carcinomas) because these cancers have a low risk of growing or spreading. In some people, the cancer might never grow and never require treatment. 

*Surgery: Most people with thyroid cancer that requires treatment will undergo surgery to remove part or all of the thyroid.

Thyroidectomy

Thyroid lobectomy

lymph node dissection

*Thyroid hormone therapy

Thyroid hormone therapy is a treatment to replace or supplement the hormones produced in the thyroid. Thyroid hormone therapy medication is usually taken in pill form.

*Radioiodine therapy

Treatment for advanced thyroid cancer:

Chemotherapy

Radiation therapy

Targeted therapy

This cancer is more likely to spread to your bones and organs, like your lungs.

Warning signs:

You might feel a lump or growth in your neck called a thyroid nodule.  Most nodules are benign.

•           Difficulty breathing or swallowing.

•           Loss of voice (hoarseness).

•           Swollen lymph nodes in your neck.

Factors causing Thyroid Cancer

Enlarged thyroid (goitre)

•           Family history of thyroid disease or thyroid cancer.

•           Inflammation of your thyroid gland.

•           Gene mutations (changes) that cause endocrine diseases, such as multiple endocrine neoplasia type 2A (MEN2A) or type 2B (MEN2B) syndrome.

•           Low iodine intake.

•           Obesity

•           Radiation therapy of head and neck especially during childhood.

•           Exposure to radioactive fallout from nuclear weapons or a power plant accident.