A 44-year-old woman has a palpable nodule in the right lobe of her thyroid gland. The nodule measures 2 cm and is firm. The rest of the thyroid gland cannot be felt and is not tender. She also describes losing weight in spite of a ravenous appetite, palpitations, and heat intolerance. She is thin, fidgety, and constantly moving, with moist skin and a pulse of 105/min. She has no exophthalmos or pretibial edema. Her TSH is reported as much lower than normal, and she has elevated levels of free T4. Which of the following is the most appropriate next step in diagnosis?
A. Exploratory neck surgery
B. MRI of the pituitary gland
C. Needle core biopsy of the thyroid mass
D. Radionuclide thyroid scan
E. Serum levels ofT3
A. Exploratory neck surgery
B. MRI of the pituitary gland
C. Needle core biopsy of the thyroid mass
D. Radionuclide thyroid scan
E. Serum levels ofT3