Thyroid Cancer - Early Signs, Risk Factors, Diagnosis, and Treatment Explained

Overview: What Is Thyroid Cancer?

Thyroid cancer is a type of cancer that starts in the thyroid gland, a small butterfly-shaped gland located in the front of your neck. The thyroid plays an important role in controlling metabolism, body temperature, heart rate, and energy levels through the release of hormones.

While thyroid cancer may sound frightening, it is one of the more treatable cancers. In fact, when detected early, the survival rate is very high. According to global cancer data, thyroid cancer accounts for about 1–2% of all cancers, with women being three times more likely to develop it than men.

The good news is that most types of thyroid cancer grow slowly and respond well to treatment. Early detection through awareness of symptoms and regular health checks makes a big difference in recovery and long-term outcomes.

What Are the Types of Thyroid Cancer?

Thyroid cancer is not a single disease; it comes in several forms. Each type behaves differently and requires a specific treatment approach:

• Papillary Thyroid Cancer (PTC): The most common type (about 80% of cases). It grows slowly and often spreads to lymph nodes in the neck. Papillary cancer usually has an excellent prognosis.
• Follicular Thyroid Cancer (FTC): Makes up 10–15% of thyroid cancers. It can spread to lungs and bones more often than papillary cancer but is still very treatable.
• Medullary Thyroid Cancer (MTC): Less common (about 2–4% of cases). It develops in the C-cells of the thyroid that make calcitonin. MTC can run in families as part of inherited genetic syndromes.
• Anaplastic Thyroid Cancer (ATC): A rare but aggressive form (about 1% of cases). It grows rapidly and is more difficult to treat.
• Other rare types: Thyroid lymphoma and thyroid sarcoma are extremely rare and treated differently.

What Are the Causes of Thyroid Cancer?

The exact cause of thyroid cancer is not always clear. However, doctors know that it develops when changes (mutations) occur in the DNA of thyroid cells. These mutations allow cells to grow uncontrollably, form a lump (nodule), and potentially spread to other parts of the body.

Known or suspected causes include:

• Genetic mutations in certain cancer-related genes.
• Radiation exposure during childhood or repeated neck X-rays in the past.
• Family history of thyroid cancer or inherited syndromes.
• Hormonal and immune system changes that may influence thyroid cell growth.

What Are the Risk Factors for Thyroid Cancer?

Not everyone with risk factors will develop thyroid cancer, but certain conditions make it more likely:

• Gender: Women are at higher risk than men.
• Age: Most cases occur between ages 30 and 60.
• Radiation exposure: Medical or environmental radiation to the head and neck.
• Family history: Inherited conditions like Multiple Endocrine Neoplasia type 2 (MEN2).
• Iodine deficiency or excess: Both can affect thyroid function (uncommon in people who use iodized salt regularly).
• Obesity and lifestyle factors: Some studies suggest links to higher risk.

What Are the Symptoms of Thyroid Cancer?

Thyroid cancer often doesn’t cause symptoms in its early stages. Many cases are discovered during routine health checks or imaging tests done for other reasons.

Common symptoms include:

• A lump or swelling in the neck that doesn’t go away.
• Changes in voice, including hoarseness.
• Trouble swallowing or breathing.
• Persistent cough not related to a cold.
• Pain in the neck or throat.
• Enlarged lymph nodes in the neck.

Advanced symptoms may include:

• Difficulty breathing due to airway compression.
• Bone pain (if cancer spreads).
• Unexplained weight loss.

How Is Thyroid Cancer Diagnosed?

Doctors use several steps to confirm thyroid cancer:

• Physical exam and medical history: A doctor will examine your neck for lumps, swelling, or any other unusual changes and ask about your overall health.
• Blood tests: To measure certain thyroid hormones and other substances, helping to assess thyroid function and overall health.
• Ultrasound of the thyroid: This non-invasive imaging technique uses sound waves to create detailed pictures of the thyroid gland, identifying the size, shape, and structure of any nodules.
• Fine Needle Aspiration Biopsy (FNAB): A thin needle is used to extract cells from the thyroid for testing. This sample is then examined by a pathologist under a microscope to check for cancer cells.
• Molecular testing: In some cases, genetic testing helps identify specific gene changes, which can help in diagnosing certain types of thyroid cancer, and determine targeted treatment options.
• Imaging Tests: MRI or CT may be used to assess how large the cancer is and whether it has spread to other parts of the neck or body.

Staging of Thyroid Cancer

Staging describes how far the cancer has spread, while grading describes how aggressive it looks under the microscope.

Stages of thyroid cancer include:

• Stage I: Cancer confined to the thyroid.
• Stage II: Cancer has grown larger or spread to nearby lymph nodes.
• Stage III: Cancer spread to tissues outside the thyroid or distant organs.
• Stage IV: Advanced cancer with widespread spread.

Staging helps doctors decide the best treatment and estimate prognosis.

What Are the Treatment Options for Thyroid Cancer?

Treatment depends on the type and stage of thyroid cancer, as well as patient age and overall health. Most people need a combination of therapies:

• Surgery:
  • Thyroidectomy: The removal of the entire thyroid gland. This is a common treatment for differentiated thyroid cancers.
  • Lobectomy: The removal of the part of the thyroid gland containing the tumor.
  • Lymph node dissection: Nearby lymph nodes may also be removed to check for and prevent cancer spread.
• Radioactive Iodine (RAI) Therapy: A dose of radioactive iodine is swallowed, which is absorbed by both healthy and cancerous thyroid cells, destroying them. Used after surgery for papillary or follicular cancers.
• External Beam Radiation Therapy: Radiation beams are aimed at the cancer from outside the body to target and destroy cancer cells.
• Systemic Therapies:
  • Targeted Therapy: These drugs, often including tyrosine kinase inhibitors, target specific characteristics of cancer cells to block growth and development.
  • Chemotherapy: Cancer-killing drugs are used to treat thyroid cancer. However, only in aggressive or advanced cancers (anaplastic).

Proton Therapy: When Is It Applicable?

Proton therapy is an advanced radiation treatment for certain thyroid cancers, offering precise targeting of tumors with protons to minimize damage to surrounding healthy tissues, which can reduce side effects like dry mouth and swallowing difficulty. While not used for all thyroid cancer cases, it's especially beneficial for patients needing a second radiation course or those at risk of significant side effects.

What Is the Prognosis for Thyroid Cancer?

The outlook for thyroid cancer is generally excellent:

• Papillary and follicular cancers: 5-year survival rates above 95%.
• Medullary thyroid cancer: 5-year survival rate around 75%.
• Anaplastic thyroid cancer: More challenging, with survival rates below 20%.

Factors that affect prognosis include:

• Age at diagnosis
• Type and stage of cancer
• Response to treatment
• Genetic mutations

Screening and Prevention of Thyroid Cancer

There are no universal screening guidelines for thyroid cancer in people without symptoms. However, screening may be recommended if you:

• Have a family history of thyroid cancer or MEN2
• Were exposed to radiation as a child
• Have thyroid nodules found during a routine exam

Prevention strategies include:

• Regular health checks
• Thyroid ultrasound when nodules are detected
• Genetic testing for families with inherited thyroid cancer risk

For International Patients

People from around the world come to Apollo Hospitals for the treatment of thyroid cancer. Our international patient services team will guide you all the way from seeking the first virtual connect all the way to treatment in India and then returning home post treatment.

Services include:

• Medical opinions and scheduling
  • Pre-arrival medical review of reports and imaging.
• Travel and logistics
  • Assistance with visa invitation letters, airport transfers, and nearby accommodation options.
  • Dedicated international patient coordinators to guide through each step.
• Language and cultural support
  • Interpreter services in multiple languages.
  • Clear, simple explanations at every stage with written care plans.
• Financial coordination
  • Transparent treatment estimates and packages when possible.
  • Support with international payment methods and insurance coordination.
• Continuity of care
  • Shared records, imaging, and treatment summaries for home doctors.
  • Telemedicine follow-ups for convenience after returning home.

Frequently Asked Questions (FAQs)

1. What is the survival rate for thyroid cancer?

The survival rate depends on the type and stage. Most thyroid cancers have survival rates above 90–95% when treated early.

2. Can thyroid cancer come back after treatment?

Yes, recurrence is possible, especially in papillary and follicular types. Regular follow-up and thyroid hormone therapy help reduce risk.

3. What are the side effects of thyroid cancer treatment?

Common side effects include low thyroid hormone levels (requiring lifelong medication), dry mouth, hoarseness, and fatigue after radiation.

4. How long does recovery take after thyroid cancer surgery?

Most patients return to normal activities in 1–2 weeks. Complete recovery, including hormone stabilization, may take a few months.

5. Is thyroid cancer curable?

Yes, most types, especially papillary and follicular, are highly curable with proper treatment.

6. How much does thyroid cancer treatment cost?

Costs vary depending on hospital, location, and type of treatment. Surgery, hospitalization, medications, and follow-up care all contribute to the overall cost. International hospitals like Apollo provide cost estimates and packages to help patients plan.

7. Can lifestyle changes reduce my risk?

Maintaining a healthy weight, avoiding unnecessary radiation exposure, and regular check-ups can help lower the risk.