How serious is a thyroid nodule?

The severity of a thyroid nodule must be determined based on its characteristics and size. Most thyroid nodules are benign, typically small, with regular shape and clear margins, and have little impact on health. If such a nodule does not cause any discomfort, there is generally no need for concern, and periodic ultrasound examinations to monitor for any changes are sufficient.

However, approximately 5% to 10% of thyroid nodules may be malignant—that is, thyroid cancer. Malignant nodules often are larger, have irregular shapes, blurred margins, and may affect surrounding tissues. If such a nodule is detected, prompt medical evaluation with detailed examinations and treatment are necessary to avoid delays.

Even if a nodule is benign, if it grows too large, it may compress the adjacent trachea or esophagus, causing difficulty breathing or swallowing. In such cases, the severity of the nodule must be assessed according to the degree of symptoms.

Once a thyroid nodule is detected, its nature should be clearly determined using methods such as ultrasound examination and fine-needle aspiration biopsy, and surgical treatment should be considered when necessary.