Primary clear cell carcinoma of the thymus and literature comparison of features.

Clear cell carcinoma arising from the thymus is considered exceedingly rare. It shows aggressive clinical behavior and demonstrates frequent local recurrences as well as widespread metastasis. The detailed clinical data of one patient with thymic clear cell carcinoma were compiled, and a review of relevant reported studies was performed. We summarized the clinical characteristics, pathological diagnosis of the patient and other reported cases. The analysis showed that older male patients were more likely to suffer, and the manifestations included chest pain and dyspnea. Some patients are asymptomatic, with the tumor being discovered during physical examination. Histologically, thymic clear cell carcinoma is composed of lobulated structures arranged in hyperchromatic fibrous stroma; the tumor cells are uniform with obvious nucleoli and clear cytoplasm. To establish the correct diagnosis, consideration and exclusion of metastasis and other original tumors in the differential diagnosis by immunohistochemistry, clinical and radiologic correlation is important.