A Case of Carcinoma Showing Thymus-Like Differentiation / 대한이비인후과학회지

ABSTRACT

Carcinoma showing tymus-like differentiation (CASTLE) was defined by Chan et al in 1991, which occurs in the thyroid gland and surrounding soft tissue, or soft tissue of the neck. It originates from ectopic thymus or branchial pouch remnants. The histologic finding shows that the tumor is divided into lobules of variable size and shape, cord with thin and thick fibrous septa, which are infiltrated by lymphocytes and plasma cells. Tumor cells consist of large vesicular nuclei, prominent nucleoli, and abundant cytoplasm. Treatment is surgical excision and prognosis is good. Differential diagnosis is squamous cell carcinoma of thyroid and lymphoepithelioma of thymus. We report a case of CASTLE that we treated by surgery and radiation therapy.