A 39-year-old woman is seen in the office for the first time. She says she has had a sensation of fullness in her neck for the past 2 months. She has no medical problems and does not smoke or drink alcohol. She had a tubal ligation 4 years ago.

Her vital signs are a blood pressure of 115/76 mm Hg, a pulse of 78 beats/min and regular, a temperature of 97.8 °F (oral), and a body mass index (BMI) of 23.6. Her general physical examination is normal except for a palpable nodule in the right lobe of her thyroid gland.