Hurthle cells seen in -

Ans. is 'b' i.e., Hashimoto Thyroiditis Pathological features of Hashimoto's thyroiditis1. Cross featureso Diffuse symmetrically enlarged thyroido Although the gland is symmetrically enlarged, the accentuation of lobulations may make the gland appear lobular on gross examination,o Capsule is intacto Cut surface is pale, yellow firm and lobulated.2. Microscopic featureso Atrophy of thyroid follicles (atrophic follicles)o Extensive lymphoplasmocytic infiltrate with abundant small lymphocytes and plasma cells with destruction of follicles.o Oncocytic metaplasia (Hurthle cell metaplasia) - The surviving follicular epithelial cells are commonly transformed into large cells with abundant pink cytoplasm and are known as Hurthle cells.o Oncocytic metaplasia (Hurthle cell metaplasia) is also known "oxyphilic change" in epithelial cells and is considered the hallmark of Hashimoto *s thyroiditis.o Varying degree of fibrosis and foci of squamous metaplasia within atrophic follicles,o Interstitial connective tissue is increased and may be abundant.