Huhle cells are seen in

Refer Robbins page no 1087thyroid is often diffusely enlarged, although more localized enlargement may be seen in some cases. The capsule is intact, and the gland is well demarcated from adjacent structures. The cut surface is pale, yellow-tan, firm, and somewhat nodular. There is extensive infiltration of the parenchyma by a mono- nuclear inflammatory infiltrate containing small lympho- cytes, plasma cells, and well-developed germinal centers (Fig. 24-11). The thyroid follicles are atrophic and are lined in many areas by epithelial cells distinguished by the presence of abun- dant eosinophilic, granular cytoplasm, termed Huhle cells. This is a metaplastic response of the normally low cuboidal follicular epithelium to ongoing injury. In fine-needle aspiration biopsy samples, the presence of Huhle cells in conjunction with a heterogeneous population of lymphocytes is character- istic of Hashimoto thyroiditis. In "classic" Hashimoto thyroiditis, interstitial connective tissue is increased and may be abundant. Unlike Reidel thyroiditis (see later), the fibrosis does not extend beyond the capsule of the gland.