What is Thyroid Cancer?
The very uncommon type of cancer, Thyroid Cancer is a disease that leads to the growth of abnormal cells in the Thyroid (neck region) of the human body.
Resembling the shape of a butterfly, the thyroid gland is in the front portion of the neck.
The gland is responsible for producing hormones that regulate the way the human body makes use of the energy stored.
Thus, when cancer affects this gland, it gets detected at the intermediate stage and treatments work just fine.
Types of Thyroid Cancer
Thyroid Cancer is divided into the following types:
- Papillary thyroid cancer: Also known as Papillary Thyroid Carcinoma, Papillary is the most common of the thyroid cancers happen to affect people.
In most of the cases, it usually affects children and is marked by an asymptomatic thyroid nodule at the neck region.
- Follicular thyroid cancer: Follicular cancer is the disease mostly diagnosed in the middle age group of people.
The alarming fact about Follicular cancer is, it has the potential to spread to other parts of the body like bones and lungs.
- Medullary thyroid cancer: It is one of the rare types of thyroid cancers and is usually caused by inherited faulty genes within a family.
Medullary thyroid cancer is characterized as a hard mass accompanied by blood vessel invasions.
- Anaplastic Thyroid Cancer: Older people are more prone to be getting infected with this type of cancer. Anaplastic thyroid is also highly common in women.
- Thyroid Lymphoma: Effecting the immune system cells of the thyroid gland, Thyroid Lymphoma cancer usually targets people over 70 years of age.
Causes of Thyroid cancer
Several inherited conditions of the human body like exposure to radiation, family history of goiter, and low levels of iodine can somewhat describe the causes of thyroid cancer.
However, the picture is still not clear as in what triggers such changes in the normal functioning of cells.
Symptoms of Thyroid Cancer
There are a lot of symptoms that can be the possible signs of thyroid cancer.
Such symptoms are mentioned below:
- Swelling in the neck
- Lump in the neck sometimes growing quickly
- Trouble in swallowing
- Trouble in breathing
- Pain in the front of the neck, sometimes going up to the ears
- Hoarseness or change in the texture of voice that does not go away
- A constant cough that is not due to cold
If you come across anyone of them, visit the doctor immediately.
Stages of Thyroid cancer
Papillary and Follicular
In the first stage of these two types of Thyroid cancers, the tumor is of any size (usually a small one) and is present in the thyroid area.
There can be chances of the infection getting spread to the nearby lymph nodes and tissues.
However, the cancer is not known to be spread to the other parts of the body at the first stage.
This is the second or one can say the final stage in Papillary and Follicular thyroid cancer.
At this stage, the cancerous tumor has spread to the other parts of the body like lungs, bones, brain, and lymph nodes.
Medullary Thyroid Cancer
In the first stage of the diagnosis of Medullary thyroid cancer, tumor (not more than 2 centimeters) is found in the thyroid region. It has not spread anywhere else.
Two conditions are likely to develop at the second stage-either the tumor has grown more than 2 centimeters but is still in the thyroid gland, or the cancerous tumor is of any size and has spread to the nearby tissues.
Lymph nodes are untouched by the tumor at this stage.
The tumor has made its way to the lymph nodes just near to the trachea and larynx (voice box).
Chances of cancer spreading to tissues just outside are thyroid are also quite possible.
Stage 4 of Medullary thyroid cancer can be explained through various substages.
- I. Stage IV A: Cancerous tumor has spread to the tissues, outside the thyroid: trachea, larynx, esophagus, and recurrent laryngeal nerve.
There lies a strong possibility of the cancerous tumor reaching the lymph nodes.
At this stage, the tumor has also made its reach to both sides of the neck or between the lungs.
- II. Stage IV B: The frontal part of the spinal column or the blood vessels between the lungs are affected by the cancerous tumor.
- III. Stage IV C: Tissues outside the thyroid gland, lungs, and bones are directly affected by the tumor.
The stages of Anaplastic thyroid cancer are quite like other types of cancers.
It begs to differ only at stage 4, which is explained as below:
- Stage IV A: Cancer is present in the thyroid region, and the chances of it spreading to the lymph nodes are quite high.
- Stage IV B: Outside tissues of the thyroid gland are also compromised by the tumor, accompanied by a big possibility of making to the lymph nodes.
- Stage IV C: This stage marks the spreading of the tumor to various parts of the human body.
Diagnosis of Thyroid Cancer
To be fully sure about the cancerous tumor, patients must undergo the process of Biopsy.
This is the most factually correct diagnosis method, in which cells from the suspicious area are taken out and thoroughly examined under a microscope.
Depending upon the condition of the lump, your doctor might also suggest some other tests.
The process makes use of ultrasonic sound waves to create images of body parts.
In this, a small instrument is known as ‘Transducer’ is placed just in front, on the skin of the neck.
Echoes of the sound waves generated after hitting the thyroid gland are received by the instrument, which further displays black and white images of the suspicious area on the screen.
This is an imaging test, which is carried on differentiating the type of thyroid cancer the patient has been infected with.
It works for papillary and follicular cancers, but not in medullary.
It is only since Medullary thyroid cancer cells do not absorb iodine.
This is done to check if the thyroid cancer has spread to the lungs or not.
Under this, an X-Ray of the chest is taken out.
Computed tomography (CT) scan
It is a special type of x-ray that is done to get detailed cross-sectional images of the human body.
CT scan is very much helpful to analyze if the cancerous tumor has spread to the other parts of the body or not.
In short, it tells the doctor about the size and location of cancer.
Unlike the normal x-ray, CT Scan takes multiple pictures, by rotating over the patient.
Magnetic Resonance Imaging (MRI) scan
Quite like the CT scan, MRI scans also provide useful information about the cancerous tumor that has made its way to the different parts of the thyroid and body.
MRI technique makes use of radio waves and strong magnets to get the images of soft tissues, affected by cancer.
Positron Emission Tomography (PET) scan
This is a special type of diagnostic test for thyroid cancer as it makes use of a radioactive substance.
This substance is usually a type of sugar, known as FDG, is injected into the bloodline of the patient.
After a while, images of the parts affected by radioactivity are obtained using a camera.
The process is helpful to detect if the patient has Medullary thyroid cancer as it does not mix up with radioactive iodine.
Thyroid-stimulating hormone (TSH)
Also known as Thyrotropin, TSH is used to check how the thyroid gland after getting infected with cancer is functioning.
TSH level in the body would be quite high if the thyroid fails to produce enough hormones.
In other words, the gland is announced to be infected by cancer.
With the help of this information, the doctor can assess as to which type of imaging tests are best suited for the patient.
T3 and T4 (thyroid hormones)
To check the functioning of the thyroid gland, the doctor may check T3 and T4 thyroid hormones.
Levels of these two hormones usually stay normal, when the gland gets affected by cancer.
Blood tests to check the levels of this hormone prove beneficial only after the treatment of cancer is done.
If the level of Thyroglobulin in the thyroid gland low, then it is a sure sign of the treatment being done properly.
For the body to use calcium efficiently, the calcitonin hormone is released in the thyroid gland.
On examining the levels of Calcitonin, possible detection of Medullary thyroid cancer can be done.
Recurrence of cancer after treatment can also be checked by testing the levels of Calcitonin.
Vocal cord exam (laryngoscopy)
It has also been seen, the vocal cord getting effected by thyroid tumors. In such a case, the procedure of laryngoscopy is carried on checking the functioning of the vocal cords.
It involves examining the vocal cord with the help of special mirrors or equipment (a thin tube with light and lens at the end).
Treatment of Thyroid Cancer
In most of thyroid cancer cases, surgery is the most opted solution.
There are different types of surgical procedures available, which are mentioned as below:
- Lobectomy: This procedure involves removal of the affected lobe, which has been diagnosed with thyroid cancer.
- Lymphadenectomy: It involves surgical removal of the lymph nodes in the neck.
- Near-total thyroidectomy: The process involves cutting off only a small part of the thyroid gland.
- Total Thyroidectomy: The whole thyroid gland is removed in this procedure.
It opts when cancer has spread to the whole of the gland.
A highly opted procedure to treat all kinds of cancers, chemotherapy make use of drugs to stop the growth of malign (cancer) cells.
While treating thyroid cancer, chemotherapy is given in two different ways.
The first method deals with the consumption of the drug directly from the mouth or injecting the drug into a vein or muscle (Systematic chemotherapy).
Whereas, in the second method, the drug is injected into the cerebrospinal fluid, or the abdomen (Regional chemotherapy).
Regional chemotherapy is used to only cure areas, which have been affected by cancer.
Chemotherapy is also highly dependent on the type of thyroid cancer the body is infected with.
Radiation therapy, including radioactive iodine therapy
Making use of high energy x-rays or some other types of radiations to cure cancer is known as Radiation therapy.
Medical science defines radiation therapy into two types-Internal Radiation therapy and external Radiation therapy.
In the first alternative, radioactive substance stored in needles, wires, or catheter, is used to kill the harmful cancer cells.
In this treatment, the apparatus (needles or wire) is placed directly to the affected area.
Whereas, in the second type of therapy, the doctor uses a machine externally to send radiations to destroy cancer cells.
Another method to treat thyroid cancer is by making use of iodine, known as Radioactive Iodine therapy.
This method is recommended for follicular and papillary thyroid cancers. Under this, the radioactive iodine is ingested through the mouth.
When the radioactive iodine gets absorbed by thyroid cells, it destroys cancer cells existing in that region.
Thyroid hormone therapy
This cancer therapy works to the core of the disease.
Hormones trigger growth of cancer cells inside the human body, and the therapy works to block the actions of them.
To prevent the body from generating thyroid-stimulating hormone (TSH), certain drugs are given to the patient.
As TSH is primarily responsible for the recurrence of cancer cells, it is this hormone that is targeted by the therapy.
As part of the process, thyroid replacement pills are given to the patients.
Targeted therapy is a treatment which attacks specific cancer cells, affecting the thyroid gland.
The treatment makes use of certain drugs and substance to identify and destroy the cancer cells.
One such therapy is the Tyrosine Kinase Inhibitor Therapy, by which signals needed for the growth of tumors can be blocked.