Q1. What is Medullary thyroid carcinoma?
Medullary carcinoma of the thyroid (MTC) is a distinct thyroid carcinoma that originates in the parafollicular C-cells of the thyroid gland. These C-cells produce calcitonin.
Q2. Commonly found in?
It occurs mostly in fifth or sixth decade of life. Medullary Thyroid Cancer is very rare. It can occur in children and adults.
Q3. Is Medullary thyroid carcinoma is fatal?
About 80% of thyroid cancers are papillary carcinomas, the most common and least aggressive cancer of the thyroid. While papillary carcinomas often spread to the lymph nodes in the neck, these cancers can usually be treated successfully and are rarely fatal. It is difficult to predict how fast metastatic Medullary thyroid cancer will progress. Though it is not curable once it has metastasized, palliative treatments such as chemotherapy and radiation can slow the cancer’s growth and improve quality of life.
Q4. What are the sign and symptoms of Medullary Thyroid Carcinoma/Cancer?
- A lump in the neck, sometimes growing quickly
- Swelling in the neck
- Pain in the front of the neck and sometimes extend to the ears
- Hoarseness of the voice
- Difficulty in swallowing
- Difficulty in breathing
- A constant cough
Q5. Where does it spread?
Sites of spread of Medullary thyroid cancer include local lymph nodes in the neck, lymph nodes in the central portion of the chest (mediastinum), liver, lung, and bones. Spread to other sites such as skin or brain occurs but rarely.
Q6. What is the survival rate for Medullary Thyroid Carcinoma?
The prognosis for patients with MTC is good. The 10-year survival rate for patients with MTC is 75% – 85%.
Q7. Investigations for Medullary Thyroid Carcinoma?
-Serum calcitonin levels: raised
-CEA (Carcinoembryonic antigen) test
-Genetic testing
-Thyroid biopsy
-USG of thyroid gland
-Fine needle aspiration cytology
Q8. Treatment for Medullary Thyroid Carcinoma?
- Surgery to remove thyroid gland and surrounding lymph nodes.
- Chemotherapy and external beam radiation.
-Stages I and II: Total Thyroidectomy is the main treatment for MTC and often cures patients with stage I or stage II MTC. Nearby lymph nodes are usually removed. Thyroid hormone therapy is needed after surgery because of removal of Thyroid gland.
Q9. What causes Medullary Thyroid Carcinoma?
There are four major types of thyroid cancer: papillary, follicular, medullary (MTC), and anaplastic. The cause of thyroid cancer is unknown, but certain risk factors have been identified which include a family history of goiter, exposure to high levels of radiation, and certain hereditary syndromes.
Q10. How do i check for Medullary Thyroid Carcinoma?
Fine needle aspiration (FNA) is one way of diagnosing thyroid cancer.
Q11. What does high level of calcitonin mean?
A low level of calcitonin means that symptoms are due to C-cell hyperplasia or medullary thyroid cancer. An increased concentration of calcitonin means that excessive amounts are being produced.
Q12. What is normal level of calcitonin?
A normal value is less than 10 pg/ml. Women and men can have different normal values, with men having higher values.
Q13. What is the function of calcitonin?
As patients who have very low or very high levels of calcitonin show no adverse effects. Calcitonin reduces calcium levels in the blood, it inhibits the activity of osteoclasts which are responsible for breaking down bones.
Q14. How to diagnose Medullary Thyroid Carcinoma?
There are several tests used to evaluate and diagnose a thyroid nodule suspicious for medullary thyroid cancer. These tests includes:
Calcitonin
A blood test to check the level of calcitonin the blood. It can also be used as a screening test for patients with a family history of MTC, who are at risk of developing the disease.
Carcinoembryonic antigen (CEA)
CEA is a substance that may be made by advanced MTC that should be tested for in the blood along with calcitonin. CEA can also be used as a marker for possible later recurrence of disease. More aggressive MTC often make more CEA.
Ultrasound
A thyroid ultrasound is a non-invasive imaging study in which sound waves are used to see an accurate picture of the thyroid gland as well as any enlarged lymph nodes. The ultrasound can tell the nodule’s size, exact location, and whether it is solid or fluid-filled (i.e. cystic).
Fine needle aspiration (FNA)
FNA biopsy is the most accurate test for evaluating thyroid nodules. A very thin needle is guided into the thyroid nodule and a small sampling of cells is aspirated or sucked into the needle. These cells are then examined under a microscope by a cytologist. The diagnosis of MTC on FNA biopsy is about 95-98% accurate.
Magnetic resonance imaging (MRI), Computed Tomography (CT scan) or Positron Emission Tomography (PETCT) scans
These advanced imaging tests may be needed to see if large cancers are invading (i.e. growing into) to the large vital structures in the neck. They can also be used to identify involved lymph nodes, spread, or recurrence.
Genetic testing
In patients whom the MTC is related with a genetic mutation, specific gene mutations should be examined by the genetic laboratory.
