Clinical presentation: A 25-year-old woman was referred for aspiration cytology of a thyroid nodule. She has been treated for Graves' hyperthyroidism for several months. On scintigraphy a "cold" nodule was diagnosed.

Palpation: a firm nodule in the lower-isthmic part of the right lobe.

Laboratory tests: TSH 3.92 mIU/L, FT4 10.4 pM/L on daily 5 mg methimazole. At the time of discovery of hyperthyroidism, the TSAb was 8.8 U/L.

Ultrasonography. The thyroid was moderately hypoechogenic and had several discrete areas. Except for the palpable nodule none of these lesions corresponded to a nodule in pathological sense. The nodule in the lower part of the right lobe was hypoechogenic and presented both perinodular and intranodular blood flow.

Cytology resulted in follicular tumor.

Histopathology disclosed follicular adenoma and in the extranodular part of the thyroid diffuse goiter corresponding to Graves' disease.

Comment.

Regarding the nodule borders this lesion does not present irregular margins. The small irregularities should not be overestimated, while the largest one is caused by the anatomical situation, the proximity of the trachea.