The thyroid is a tiny butterfly-shaped gland located at the base of the throat and is a component of the endocrine system. It produces hormones that regulate the metabolic rate, heart rate, and body temperature. Thyroid cancer develops when cancer cells form in the gland. A mass of cancer cells – the malignant tumor is capable of spreading into neighboring areas. While there are multiple forms of thyroid cancer, papillary thyroid carcinoma is the most prevalent.

In approximately 70–80% of cases, it often affects only one lobe of the thyroid gland. About 20% of thyroid cancer cases are follicular thyroid carcinoma.

Types of thyroid cancer
Researchers have uncovered four primary categories of thyroid cancers:

Papillary thyroid carcinoma
If a person is detected with thyroid cancer, they are more likely to be this type. Although it frequently invades the lymph nodes in your neck, its growth is typically modest. So, the patient still stands a strong chance of recovering fully.

Follicular thyroid cancer
17-20% of thyroid malignancies diagnosed around the world are follicular thyroid tumors. In addition to easily spreading into your blood vessels, it can also expand into your lymph nodes.

Medullary cancer
4% of thyroid cancer cases reported are medullary cancer. It can be identified earlier in a blood test to rule out elevated calcitonin levels. The thyroid gland produces an abnormal amount of calcitonin in cancerous conditions.

Anaplastic thyroid cancer
It is the most dangerous type of thyroid cancer that spreads quickly to other body parts, is a rare form, and is very challenging to treat.

Causes
Thyroid cancer develops because of DNA changes in thyroid cells. These DNA changes, or mutations as they are known in science, command the cells to multiply and spread out swiftly. A tumor is a growth of cells that takes the form of a mass.
DNA abnormalities cause most thyroid cancer cases, but the exact cause of these alterations is unknown. However, some risk factors can increase the chances of getting thyroid cancer. They are:

Family history
If a member of a family lineage has thyroid cancer, then the chances of a close relative getting the disease are greater.

Goitre
A person with a history of Goitre is more susceptible to developing certain types of thyroid cancer. Goitre occurs as a result of iodine deficiency.

Exposure to radiation
Radiation exposure, especially to the head and neck, in childhood greatly increases the chances of getting thyroid cancer.

Acromegaly
This refers to a condition where the body produces excess growth hormone.

The neck lymph nodes and surrounding tissue may become infiltrated by the tumor as it grows (metastasizes). On rare occasions, the cancer cells might move from the neck to the lungs, bones, and other body parts.

Symptoms and signs
Not all thyroid cancer types may show early signs or symptoms. One might only see the indications when the tumor grows in size. There are other conditions also that mimic the symptoms of thyroid cancer. So, it can only be confirmed with a physical examination, genetic test, blood test, or a biopsy.
Most thyroid malignancies are asymptomatic in the early stages of the disease. As cancer progresses, it may lead to:

• A nodule (lump) on your neck that can be felt through the skin
• The impression that tightly fitting shirt collars are becoming overly restrictive
• Alterations to your voice, such as hoarseness
• Having trouble swallowing
• Neck lymph nodes that are swollen
• Difficulty breathing
• Neck and throat pain
• Persistent cough

Treatment options
The cancer type, tumor size, and whether it has metastasized will all determine the treatment type. Thyroid cancer is usually manageable, even in more advanced stages. Some of the treatments include:

Surgery
Most thyroid cancer patients who require surgery have their thyroid gland partially or completely removed. Depending on the type of thyroid cancer, the extent of the tumor, and whether the cancer has spread to the lymph nodes in addition to the thyroid, the medical team may advise a certain procedure. The surgery may impact the body’s ability to generate thyroid hormones. If so, thyroid hormones can be provided with oral supplements. After surgery, a laryngoscopy may be done to check if the vocal cords are functioning properly.

Chemotherapy
Chemotherapy is used to treat cancer cells. Strong chemicals are either injected into a vein or consumed orally. In case of anaplastic thyroid cancer, the doctor may prescribe this in addition to radiation.

Radioiodine therapy
All of the iodine in the body is absorbed almost entirely by the thyroid gland. So, consuming radioactive iodine will help harness the thyroid’s ability to kill cancer cells, which can improve the health condition. It is most frequently applied to differentiated thyroid tumors without any risk of metastasizing to other body regions. Since not all types of thyroid cancer respond to this treatment, it has to be first tested to see whether cancer will likely benefit from radioactive iodine. Papillary, follicular, and Hurthle cell types of differentiated thyroid carcinoma are more likely to respond. Radioactive iodine is typically not used to treat anaplastic and medullary thyroid cancers.

Targeted drug therapy
Scientists have created new methods to target the internal changes in cells that give rise to cancer. Drugs for thyroid cancer targeted therapy comes in a wide variety. Some destroy the blood vessels cancer cells produce, while others target particular gene alterations. A third category is kinase inhibitors, which prevent the protein kinase from instructing other cells to grow.

Conclusion
Most thyroid cancer types are curable with treatment, especially if the tumor has not spread to other body parts. After getting proper treatment, patients must strictly follow up with routine check-ups. These routine checkups will help the healthcare professional look into your progress as well as decide any other preventive measures to be taken.