24-year-old woman is evaluated for a lump in her neck. She discovered the lump a week ago while showering.
The patient feels well and has no associated pain, fever, night sweats, or weight changes. Her medical history is
unremarkable, although she has had irregular menses for a year since insertion of an intrauterine device. The
patient does not use tobacco, alcohol, or illicit drugs. Her mother died during surgery for thyroid cancer. Blood
pressure is 133/80 mm Hg and pulse is 78/min. On examination, there is a palpable 2-cm nodule in the right
thyroid lobe. The remainder of the examination, including chest, abdomen, extremities, and skin, is normal.
Serum TSH and calcium levels are normal and calcitonin is elevated. Ultrasound-guided aspiration biopsy reveals
malignant cells. Which of the following tests is the best next step in evaluation of this patient?
- 0 A. Aldosterone-renin activity ratio
- 0 B. Late-night salivary cortisol
- O C. Low-dose dexamethasone suppression test
- O D. Plasma fractionated metanephrine assay
- 0 E. Plasma insulin-like growth factor-1
- 0 F. Serum prolactin assay
0 voters