Thyroid nodules

Choose the content to read

• What are Thyroid nodules?
• Types of thyroid nodules
• Symptoms of thyroid nodules
• Diagnosis
• Treatment

Thyroid nodules

The thyroid gland location is in the midline between the larynx and the collarbones. Its function is to secrete triiodothyronine (T3) and thyroxine (T4), which are hormones regulating metabolism and energy reserve. Thyroid nodules typically are circular or oval shapes. They are ubiquitous; at least half of people have a nodule. Around 95% of the thyroid nodules are benign.

Types of thyroid nodules

Benign

• Multinodular goiter
• Hashimoto's thyroiditis
• Colloid, simple, or hemorrhagic cysts
• Follicular adenomas

Malignant

• Papillary carcinoma
• Follicular carcinoma
• Medullary carcinoma
• Anaplastic carcinoma
• Primary thyroid lymphoma
• Metastatic carcinoma from breast, renal cell carcinoma, etc.

Symptoms of thyroid nodules

Almost all thyroid nodules are asymptomatic, but large nodules can be felt and visible. They may press on your esophagus, leading to difficulty swallowing or dyspnea. If thyroid nodules secrete extra thyroxine, it can cause hyperthyroidism. You may sweat excessively, lose weight without a known cause, develop fast or irregular heart rhythm, and experience tremors and irritability.

When to see a doctor

Though most thyroid nodules are not cancerous, it is advisable to have a proper diagnosis if you develop the previously mentioned symptoms, particularly when you have difficulty breathing and swallowing.  

If you lose weight despite regular or increased appetite, have difficulty sleeping, become restless, or develop muscle weakness, you should see a doctor to rule out hyperthyroidism.

If you feel cold, readily tired, depressed, develop dry skin, experience constipation, or have memory problems, these can be signs of hypothyroidism.  

Complications

• Dysphagia is caused by compression of the esophagus by the thyroid nodule.
• Hyperthyroidism, which can increase the risk of cardiac arrhythmias, osteoporosis, and thyroid storm, is rare but life-threatening.  
• Thyroid hormone deficiency, secondary to the surgical gland removal, will require lifelong thyroid replacement therapy.

Diagnosis

• A physical exam includes examining your thyroid by asking you to swallow to check for nodules. In addition, doctors will check for signs of hyperthyroidism and hypothyroidism.  
• Thyroid function tests measure the thyroid-stimulating hormone (TSH) blood levels and ascertain if you have hypothyroidism or hyperthyroidism.
• Ultrasound can distinguish between a cystic and a solid nodule and enumerate the number of nodules.   
• Ultrasound-guided fine-needle aspiration biopsy, performed as an outpatient procedure, usually takes around 20 minutes. 
• Thyroid scan: taking radioactive iodine isotope for imaging of the thyroid gland. The nodules that secrete surplus thyroid hormone would absorb more isotopes than regular thyroid tissue. These types of nodules, known as hot nodules, are usually noncancerous. Nodules that absorb fewer isotopes are cold nodules, which often are cancerous and require further diagnostic confirmation.

Treatment

Treatment for benign nodules

1. Active surveillance
   A regular physical exam and thyroid function tests are required to check if your nodules grow or change.
   • Thyroid hormone therapy
   • Surgery
     Your doctor may recommend surgical removal of the thyroid nodule if they constrict your airways or esophagus, as well as nodules suspicious of being cancer.
2. Treatment for hyperthyroid nodules
   • Radioactive iodine therapy
     You will have to take radioactive iodine in the form of capsules or liquid that can help shrink the nodules. Your symptoms usually improve within a few months.  
   • Anti-thyroid medications 
     It is a long-term treatment. You can take methimazole to relieve hyperthyroid symptoms.
   • Surgical removal
3. Thyroid cancer treatment
   • Partial thyroidectomy and total thyroidectomy 
     After the surgical removal, you will require lifelong thyroid hormone replacement therapy. Possible risks of this type of treatment include damage to the nerve innervating the vocal cord and the parathyroid glands.