A palpable nodule on the right lobe of the thyroid gland is detected in a 55-year-old woman. The nodule is firm and nontender and moves freely. The lymph nodes in her neck are not enlarged.
HISTORY AND PHYSICAL EXAMINATION
The patient takes a statin for mild hypercholesterolemia and occasionally takes a proton pump inhibitor for heartburn. She has no history of organic heart disease, hypertension, chronic obstructive pulmonary disease, or diabetes; there is no family history of thyroid disease or other endocrinopathy. Except for the thyroid nodule, physical findings are normal.
LABORATORY AND IMAGING RESULTS
Hemogram is normal. Total cholesterol level is 201 mg/dL. Serum calcium level is 9.7 mEq/L; phosphorus, 4.0 mEq/L. The rest of the results of a chemistry panel are normal. Thyroid-stimulating hormone (TSH) level is normal.
Ultrasonography reveals a 2.3-cm solid nodule in the right lobe of the thyroid gland and two 0.5-cm nodules nearby in the same lobe. No microcalcifications or vascular spots are seen. Fine-needle aspiration (FNA) biopsy of the thyroid gland is scheduled.
Which of the following statements about the management of this patient's thyroid nodules is true?
A. If FNA biopsy reveals papillary carcinoma, lobectomy is the optimal therapy.
B. If the FNA biopsy specimen is deemed "suspicious," a battery of immunohistochemical stains can reliably differentiate benign from malignant disease.
C. If the FNA biopsy specimen is deemed "suspicious," yearly ultra- sonography is the optimal management strategy.
D. If results of the FNA biopsy are inconclusive, repetition of FNA under ultrasound guidance can reduce the likelihood of a nondiagnostic smear from 15% to less than 5%.
1. Castro MR, Gharib H. Continuing controversies in the management of thyroid nodules. Ann Intern Med. 2005;142:926-931.
2. Hegedus L. Clinical Practice. The thyroid nodule. N Engl J Med. 2004;351: 1764-1771.
3. Utiger RD. The multiplicity of thyroid nodules and carcinomas. N Engl J Med. 2005;352:2376-2378.
4. Shattuck TM, Westra WH, Ladenson PW, Arnold A. Independent clonal origins of distinct tumor foci in multifocal papillary thyroid carcinoma. N Engl J Med. 2005;352:2406-2412.