Enlarged thyroid gland with normal thyroid function tests.

A 41-year-old woman had a 1to 2-cm asymptomatic thyroid mass, which had been monitored by an endocrinologist for several years with serial sonography. Noting that it had enlarged in the face of normal thyroid function tests, the endocrinologist ordered a fine-needle aspiration biopsy, which showed a cellular follicular lesion. Although some of the nuclear changes seen in papillary carcinoma were present, the cells did not fulfill all of the cytologic criteria for that diagnosis. The patient was referred to Baylor University Medical Center for surgery; she brought with her two ultrasound images (Figure 1) and a chest x-ray that showed a minimal leftward deviation of the trachea.