What are the types of thyroid cancers?

Data from the National Cancer Institute shows that every year more than 44,000 people are diagnosed with thyroid cancer, even though it is less prevalent than many other forms of cancer. In the initial phase of disease, thyroid cancer can be asymptomatic, and difficult for any expert like an Oncologist in Lahore to diagnose. However, with the growth of the tumor, there is pain, swelling and other symptoms. Read on to know more about thyroid cancer and its types:

What is thyroid cancer?

Thyroid gland is a butterfly-shaped gland located at the base of the neck just beneath the larynx, and produces thyroid hormones—T3 and T4, which regulate body temperature, heart rate and the basal metabolic rate. Cancerous growth of the healthy thyroid cells can enlarge the gland and produce too much of the thyroid hormone, thereby producing symptoms like palpitations, weight gain or weight loss. 

Thyroid cancer can be benign or malignant, with the benign form remaining localized, and the malignant form spreading to other organs of the body. In some forms of enlarged growths, the thyroid gland is called thyroid nodule; 90 percent of all thyroid nodules are benign. 

Factors that predispose one to thyroid cancer include: female gender, age between 25 and 65 years and Asian ethnicity. The chances of thyroid cancer also rise with previous history of radiation exposure, history of goiter, obesity, iodine deficiency and family history of genetic mutations. Radiation exposure refers to both—beam radiation and radiation events like Chernobyl. 

What are the symptoms of thyroid cancer?

As mentioned before, the early phase of disease is asymptomatic. Later, there is:

• Difficulty in swallowing 
• Involvement of lymph nodes of the neck
• Palpable lump in the neck 
• Pain and swelling in the neck and throat 
• Changes in the voice with increased hoarseness 
• Discomfort in moving the neck and head 
• Persistent cough

What are the types of thyroid cancer?

There are five main types of thyroid cancer:

• Follicular thyroid cancer 
• Papillary thyroid cancer
• Medullary thyroid cancer 
• Hurthle cell thyroid cancer 
• Anaplastic thyroid cancer 

How is thyroid cancer diagnosed?

The diagnosis of thyroid cancer is based on the following investigations:

• Blood tests: the first step of diagnosis is to determine the levels of thyroid hormones and whether they are increased or decreased as a result of thyroid disease.  
• Radioiodine scan: a pill with radioactive iodine is given to the patient, and this iodine is taken up by the thyroid cells in the body. This investigation makes it easier to diagnose metastasis of thyroid cancer.  
• Biopsy: cells of the thyroid are removed through fine needle aspiration biopsy to test for dysplasia and cancerous growth. To check whether the lymph nodes are involved or not, sentinel lymph node biopsy is performed.  
• Imaging techniques: investigations like CT/MRI and PET scan not only detect tumor size, but also look for spread to other organs.   

What are the treatment options?

The mainstay of treatment for thyroid cancer is surgery; surgery safely removes the cancerous growths and for complete remission, surgery is followed by chemotherapy, radiation therapy and hormone therapy. 

Surgery: the healthcare provider can choose to remove part of the thyroid gland—known as lobectomy, or the whole of the thyroid gland—thyroidectomy. When the cancer involves the lymph nodes, they are also removed during surgery. 

Radioiodine therapy: radioactive iodine treatment is used after surgery to remove left-over cells and to prevent recurrence of cancer. This treatment is available as pills and capsules to be swallowed. 

Chemo- and radio-therapy: intravenous forms of chemotherapeutic drugs are used to kill the cancerous cells and stop their spread. Similarly, strong beams of external radiation therapy and brachytherapy (internal radiation therapy) are used to kill the cancerous cells. 

Hormone therapy: 

Once the thyroid gland is removed, the patient is put on medication called levothyroxine by their healthcare provider like an Oncologist in Karachi for life. This medication replaces the endogenous thyroid hormones and are therefore needed for life.