Medullary Thyroid Cancer (MTC): Symptoms, Causes, Treatment

What are the symptoms of medullary thyroid cancer?

Medullary thyroid cancer is a type of thyroid cancer that arises from the C cells of the thyroid gland. The symptoms of medullary thyroid cancer are often nonspecific and can be similar to those of other thyroid conditions. Here are some common symptoms of medullary thyroid cancer:

1. Swollen lymph nodes in the neck: Medullary thyroid cancer often spreads to the lymph nodes in the neck, causing swelling and tenderness.
2. Hoarseness: As the tumor grows, it can compress the vocal cords, causing hoarseness or changes in the voice.
3. Difficulty swallowing: The tumor can also compress the esophagus, making it difficult to swallow food and liquids.
4. Pain: Patients with medullary thyroid cancer may experience pain in the neck, shoulder, or arm on one side of the body.
5. Weight loss: Unexplained weight loss is a common symptom of medullary thyroid cancer.
6. Fatigue: Patients with medullary thyroid cancer may experience fatigue, which can be caused by anemia, hypocalcemia, or other factors.
7. Headaches: Some patients may experience headaches due to increased blood pressure or hormonal changes.
8. Dizziness or lightheadedness: Medullary thyroid cancer can cause hormonal imbalances, leading to dizziness or lightheadedness.
9. Enlargement of the parathyroid glands: The parathyroid glands can become enlarged due to hormonal imbalances, leading to symptoms such as anxiety, palpitations, and tremors.
10. Hypercalcemia (elevated calcium levels): Medullary thyroid cancer can cause hypercalcemia, which can lead to symptoms such as abdominal cramps, constipation, and kidney stones.

It’s essential to note that many of these symptoms can also be caused by other conditions, and a diagnosis of medullary thyroid cancer requires a thorough evaluation by a healthcare provider. If you experience any unusual symptoms, it’s crucial to consult a doctor for proper evaluation and treatment.

What are the causes of medullary thyroid cancer?

Medullary thyroid cancer is a type of thyroid cancer that arises from the C cells of the thyroid gland. The exact causes of medullary thyroid cancer are not fully understood, but several risk factors have been identified:

1. Genetic mutations: Mutations in the RET proto-oncogene, which is responsible for regulating the development and function of the thyroid gland, are a major risk factor for medullary thyroid cancer. This genetic mutation can be inherited or acquired.
2. Multiple Endocrine Neoplasia type 2 (MEN2): MEN2 is a rare genetic disorder that increases the risk of developing medullary thyroid cancer, as well as other endocrine tumors, such as pheochromocytoma and parathyroid adenomas.
3. Familial Medullary Thyroid Carcinoma (FMTC): FMTC is a rare genetic disorder that affects families with a history of medullary thyroid cancer. It is caused by mutations in the RET gene and is often associated with other endocrine tumors.
4. Radiation exposure: Exposure to ionizing radiation, such as during radiation therapy for other cancers or nuclear accidents, can increase the risk of developing medullary thyroid cancer.
5. Environmental factors: Exposure to certain environmental factors, such as radiation from nuclear power plants or contaminated soil, may also contribute to an increased risk of medullary thyroid cancer.
6. Family history: A family history of medullary thyroid cancer or other endocrine tumors increases the risk of developing the disease.
7. Age: Medullary thyroid cancer is more common in people over the age of 40.
8. Sex: Women are more likely to develop medullary thyroid cancer than men.
9. Thyroid nodules or cysts: The presence of thyroid nodules or cysts can increase the risk of developing medullary thyroid cancer.

It’s essential to note that most cases of medullary thyroid cancer occur sporadically, without any known genetic or environmental risk factors.

How is the diagnosis of medullary thyroid cancer made?

The diagnosis of medullary thyroid cancer is typically made through a combination of physical examination, medical history, laboratory tests, and imaging studies. Here are the steps involved in making a diagnosis of medullary thyroid cancer:

1. Physical Examination: A thorough physical examination is performed to check for any signs of thyroid enlargement, nodules, or masses.
2. Medical History: A detailed medical history is taken to identify any symptoms, such as hoarseness, difficulty swallowing, or weight loss.
3. Laboratory Tests:
   • Thyroid function tests: Blood tests are done to check thyroid function, including TSH (thyroid-stimulating hormone), T4 (thyroxine), and T3 (triiodothyronine).
   • Calcitonin levels: Calcitonin is a hormone produced by C cells in the thyroid gland. Elevated calcitonin levels can indicate medullary thyroid cancer.
   • Thyroglobulin levels: Thyroglobulin is a protein produced by the thyroid gland. Elevated thyroglobulin levels can indicate thyroid cancer.
4. Imaging Studies:
   • Ultrasound: A thyroid ultrasound is performed to visualize the thyroid gland and detect any nodules or masses.
   • Computed Tomography (CT) scan: A CT scan is used to evaluate the size and extent of the tumor and to rule out metastasis to other parts of the body.
   • Magnetic Resonance Imaging (MRI): An MRI may be used to evaluate the tumor’s relationship to surrounding structures, such as the trachea and esophagus.
5. Fine Needle Aspiration Cytology (FNAC): FNAC is a procedure in which a fine needle is inserted into the thyroid nodule or mass to collect cells for microscopic examination. This can help confirm the presence of cancerous cells.
6. Surgical Biopsy: A surgical biopsy may be performed if the diagnosis is still unclear after FNAC or if the tumor is large enough to be removed surgically.

A multidisciplinary team of healthcare providers, including endocrinologists, surgeons, radiologists, and pathologists, work together to diagnose and manage patients with medullary thyroid cancer.

What is the treatment for medullary thyroid cancer?

The treatment for medullary thyroid cancer typically involves a combination of surgery, radioactive iodine therapy, and chemotherapy. The specific treatment plan depends on the stage and severity of the disease, as well as the patient’s overall health.

Surgery:

• Total thyroidectomy: This is the most common treatment for medullary thyroid cancer. The entire thyroid gland is removed to ensure that all cancerous tissue is removed.
• Central neck dissection: This involves removing lymph nodes in the central part of the neck to remove any cancerous tissue.
• Lateral neck dissection: This involves removing lymph nodes on the sides of the neck to remove any cancerous tissue.

Radioactive Iodine Therapy:

• Radioactive iodine (I-131) is a radioactive form of iodine that is used to kill any remaining cancer cells in the thyroid gland.
• This treatment is typically given after surgery to ensure that all cancerous tissue is removed.

Chemotherapy:

• Chemotherapy may be used in combination with radioactive iodine therapy or as a single treatment option.
• The most commonly used chemotherapy drugs for medullary thyroid cancer are doxorubicin, cisplatin, and 5-fluorouracil.

Targeted Therapy:

• Targeted therapy involves using medications that specifically target the genetic mutations that are driving the growth of the cancer.
• Examples of targeted therapies used to treat medullary thyroid cancer include vandetanib and cabozantinib.

Palliative Care:

• Palliative care is an important part of treating medullary thyroid cancer, especially in advanced stages.
• Palliative care can help manage symptoms such as pain, fatigue, and shortness of breath.

Follow-up Care:

• After treatment, patients will need regular follow-up appointments with their healthcare provider to monitor for recurrence or spread of the cancer.
• Imaging tests, such as CT scans or PET scans, may be used to monitor for recurrence or spread.

It’s important to note that each patient’s treatment plan will be tailored to their individual needs and circumstances. Patients should work closely with their healthcare provider to develop a treatment plan that is right for them.