Clinicopathologic Features of Warthin-Like Subtype of Papillary Thyroid Carcinoma

This study aimed to explore the clinicopathological characteristics, immunophenotype, histologic occurrence, diagnosis, and differential diagnosis of the Warthin-like variant of papillary thyroid carcinoma. The clinical features, thyroid fine-needle aspiration cytology, histomorphology, and immunohistochemistry results of 4 cases of Warthin-like variant of papillary thyroid carcinoma were analyzed, and related published studies were reviewed. Three of the 4 patients were female and one male, aged 46 to 73 years, with a median age of 61.5 years. The tumors were 0.8 to 1.5 cm in size and gray-white, solid or partially cystic nodules with a hard texture. The microscopic examination revealed tumor cells in the context of Hashimoto thyroiditis, which were histologically similar to Warthin tumor of the salivary glands, with a large number of lymphocytes and some plasma cells in the papillary structure. The tumor cells had features typical of papillary carcinoma, with abundant and eosinophilic cytoplasm. The results of the immunohistochemical analysis were as follows: TTF-1, CK19, and galectin-3 were positive, whereas thyroglobulin and CD56 were negative. Warthin-like variant of papillary thyroid carcinoma is a rare thyroid malignancy. Its unique morphology is helpful for diagnosis and differential diagnosis, and its prognosis is relatively good.