Figure 4b. Hashimoto thyroiditis manifesting as a multinodular goiter in a 51-year-old man who presented with multiple palpable thyroid nodules. Laboratory values were as follows: FT4 = 0.7 ng/dL, T3 = 95 ng/dL, and TSH = 6.1 µIU/mL. The 24-hour RAIU was 40%. (a) Anterior image demonstrates an enlarged thyroid with both cold (thin arrows) and "hot" (thick arrows) nodules. (b) Photomicrograph (original magnification, x100; H-E stain) of a histologic specimen of the large, cold nodule in the left lower pole reveals lymphocytes surrounded by large islands of colloid (arrow).