Symptoms

Most thyroid nodules don't cause signs or symptoms. But occasionally some nodules become so large that they can:

• Be felt
• Be seen, often as a swelling at the base of your neck
• Press on your windpipe or esophagus, causing shortness of breath or difficulty swallowing

In some cases, thyroid nodules produce additional thyroxine, a hormone secreted by your thyroid gland. The extra thyroxine can cause symptoms of an overproduction of thyroid hormones (hyperthyroidism), such as:

• Unexplained weight loss
• Increased sweating
• Tremor
• Nervousness
• Rapid or irregular heartbeat

Only a small number of thyroid nodules are cancerous. But determining which nodules are cancerous can't be done by evaluating your symptoms alone. Most cancerous thyroid nodules are slow growing and may be small when your doctor discovers them. Aggressive thyroid cancers are rare with nodules that may be large, firm, fixed and rapid growing.

When to see a doctor

Although most thyroid nodules are noncancerous and don't cause problems, ask your doctor to evaluate any unusual swelling in your neck, especially if you have trouble breathing or swallowing. It's important to evaluate the possibility of cancer.

Seek medical care if you develop signs and symptoms of hyperthyroidism, such as:

• Sudden weight loss even though your appetite is normal or has increased
• A pounding heart
• Trouble sleeping
• Muscle weakness
• Nervousness or irritability

Also see your doctor if you have signs and symptoms that may mean your thyroid gland isn't making enough thyroid hormone (hypothyroidism), which include:

• Feeling cold
• Feeling tired more easily
• Dry skin
• Memory problems
• Depression
• Constipation