light and electron microscopic study of the thyroid gland and an enlarged cervical lymph node in a 75-year-old woman with hashimoto 's thyroiditis disclosed immunoblastic proliferation in the lymph node , marked by collections of striking round cells positive to periodic acid-schiff ( pas ) staining , immunoblasts and plasmacytoid elements in a vascular , fibrous framework .
C0040132
thyroid gland
C0677607
hashimoto 's thyroiditis