Less than 1% of all cancers are present in the thyroid, yet thyroid nodules are found in 4 to 10% of the adult population. Because thyroid nodules are relatively common, the diagnostic dilemma is to distinguish between a more common benign nodule, which usually does not require specific treatment, and a malignant nodule, which requires thyroidectomy and further treatment. Thyroid nodules usually are an incidental finding on a routine examination by a primary care physician. When patients seek treatment for symptomatic nodules, a more serious problem may be indicated, and thyroid cancer is suggested. However, additional studies have demonstrated the use of genetic markers and immunohistochemistry in the diagnosis of thyroid nodules, which may lead to a more rational approach to the treatment. This article reviews literature published in the last 12 months pertaining to the pathogenesis, diagnosis, and treatment of thyroid nodules.