Thyroid nodules are lumps that form in the thyroid gland, which is located in the neck. They can be either benign (noncancerous) or malignant (cancerous). They can vary in size from very small to large. Symptoms of thyroid nodules may include a lump in the neck, difficulty swallowing, hoarseness, or shortness of breath. Treatment for thyroid nodules depends on the type and size of the nodule.