Partial Thyroidectomy, Thyroidectomy, Total Thyroidectomy Nearly half of all Americans are likely to have a thyroid nodule — solid or fluid-filled lump — sometime in their lives. One or more of these nodules may develop in the thyroid gland. Most of them are non-cancerous (benign). However, about 5% to 10% of thyroid nodules are cancerous (malignant), and require prompt and appropriate treatment. The thyroid is a gland located at the base of the neck, just below the Adam's apple. Although very small, it makes a big difference in our health. An endocrine gland, it is a part of the human body that secretes hormones. The thyroid produces hormones that regulate many of the body's basic functions, such as how fast the heart beats and how quickly calories are burned. Thyroid nodules, whether benign or malignant, rarely cause any symptoms. Most of the time, they are discovered by self-examination, by a physician or incidentally during some x-ray test of the neck being performed for unrelated reasons. A very large nodule can sometimes cause some difficulty swallowing and occasionally shortness of breath. If a patient with a thyroid nodule develops a hoarse, weak voice, then thyroid cancer is a concern. Other risk factors for malignancy in a thyroid nodule are prior history of radiation exposure and family history of thyroid cancer.