Cytologic Findings of Thyroid Carcinoma Showing Thymus-like Differentiation: A Case Report

• Published in: Journal of pathology and translational medicine Vol. 46; no. 3; pp. 302 - 305
• Main Authors: Chang, Sunhee, Joo, Mee, Kim, Hanseong
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Society of Pathologists, Korean Society for Cytopathology 01.06.2012; The Korean Society of Pathologists and The Korean Society for Cytopathology; 대한병리학회
• Subjects: Cancer; Case Report; Conflicts of interest; Cytoplasm; Molecular weight; Thyroid cancer; Thyroid gland; Tumors; 병리학; Thyroid gland; Biopsy, fine-needle; Cytodiagnosis; Thymus gland; Thymoma
• ISSN: 1738-1843; 2383-7837; 2092-8920; 2092-8920; 2383-7845
• DOI: 10.4132/KoreanJPathol.2012.46.3.302

Carcinoma showing thymus-like differentiation (CASTLE) is a rare carcinoma of the thyroid or adjacent soft tissue of the neck with a histologic resemblance to thymic epithelial tumors. Although the fine-needle aspiration (FNA) plays a central role in the initial evaluation of thyroid nodules, few reports about the cytologic findings of CASTLE have been found according to a review of literatures. We report cytologic findings of a case of CASTLE. A 34-year-old woman presented with a 2-month history of sore throat. The FNA showed that the smear was composed of three dimensional clusters and sheets. The tumor cells were round to ovoid with high nuclear : cytoplasmic ratios. The nuclei were vesicular with small nucleoli. There were some tumor cells showing keratinization. Some lymphocytes were found on the background and within clusters. The presence of poorly-differentiated tumor cells with a focal keratinization and a lymphocytic background on the FNA is suggestive of CASTLE.