Thyroid Nodules and Malignancy

The prevalence of palpable thyroid nodules in the US population is estimated to be 4–7 % in adults. By contrast, autopsy studies have shown that thyroid nodules are present in a much higher percentage of people – up to 50 % of adults – demonstrating that most nodules are rarely clinically detected. An aging population and the use of high-resolution ultrasonography have raised our awareness of non-palpable nodules. The challenge, thus, arises in differentiating nodules that are clinically significant from those that are not. Thyroid cancer remains an infrequent cause of malignancy, accounting for an estimated 1 % of cancer diagnoses per year. Although thyroid carcinoma typically follows an indolent course, some tumors are aggressive and capable of progressing to metastatic disease. This highlights the importance of early identification and appropriate treatment.