Fig. 4.

Bilateral anaplastic cancers in 51-year-old woman (Pt. No. 6).

A. Thyroid scan shows large heterogeneous hyperfunctioning nodule in left lobe of thyroid gland. B. On ultrasonography, heterogeneous isoechoic, round, smoothly marginated, solid nodule is observed at left thyroid gland. It was classified as suspicious malignant nodule of 4.4 cm maximal dimension, and was indicated with fine needle aspiration. It was surgically proven to be anaplastic thyroid cancer. 0.4 cm indeterminate nodule at right thyroid gland was also proven to be anaplastic carcinoma (not shown). C. 1.8 × 1.8 cm anaplastic thyroid carcinoma is seen under background of follicular carcinoma in left lobe. Follicular carcinoma on right side (neoplastic follicles) transits to anaplastic carcinoma on left side (× 100, H&E).